172 Sentences With "pressure wave" | Random Sentence Generator

But there's also a pressure wave thats created from the explosion itself.

The primary mechanism of injury — the blast pressure wave itself — is less understood.

A secondary mechanism: Wind rushes to fill the vacuum left by the pressure wave.

They're shaped like this: These shock waves are all different strengths, and they as they travel through the air, they coalesce into just two powerful waves — a strong positive pressure wave at the nose and a strong negative pressure wave at the tail.

But the real damage, Lance said, probably occurred when the pressure wave reached their lungs.

They posited that the bubble generated a pressure wave in the fluid, producing a sound.

With each heartbeat a pressure wave rippled out from his heart and risked tearing the artery.

An initial explosion produces a pressure wave powerful enough to flatten buildings or penetrate into cave or other structures.

" Another user named Christopher Keller described them as akin to a sonic boom, saying he felt a "pressure wave.

Indeed, the nuclear blast has three components — heat, pressure wave, and radiation — and was unprecedented in its ability to kill en masse.

Occasionally, something — unexpected fireworks or the pressure wave from subwoofers at a concert — thrusts me back into that day, five years gone.

TBI can come from falls, bullets shrapnel, or the blast pressure wave that comes from explosions, such as from enemy improvised explosive devices (IEDs).

Smaller sized ones, which are much more common in our solar neighborhood, tend to explode while they're still in the sky, creating a pressure wave that propagates outwards in all directions.

These produce a sort of standing pressure wave that can hold an object up or, if the pressure is coming from multiple directions, hold it in place or move it around.

"Pressure Wave Meditations I - XXIII" is largely a piece of small changes, but when the dramatic jumps happen, it suggests a dream-like lapse, like watching footage of a flowering forest that cuts rapidly between real-time and montage-y superspeed.

For example, an 8 gram projectile at 360 m/s impacting a NIJ level II vest over the sternum can produce an estimated pressure wave level of nearly 2.0 MPa (280 psi) in the heart and a pressure wave level of nearly 1.5 MPa (210 psi) in the lungs. Impacting over the liver can produce an estimated pressure wave level of 2.0 MPa (280 psi) in the liver.

It ultimately concluded that no "conclusive evidence could be found for permanent pathological effects produced by the pressure wave".

As with the arterial pressure wave, a normal pulse volume tracing has a brisk upstroke and a dicrotic notch.

There is a significant body of evidence that Hydrostatic shock (more precisely known as the ballistic pressure wave) can contribute to handgun bullet effectiveness. Recent work published by scientists M Courtney and A Courtney provides compelling support for the role of a ballistic pressure wave in incapacitation and injury. This work builds upon the earlier works of Suneson et al. where the researchers implanted high-speed pressure transducers into the brain of pigs and demonstrated that a significant pressure wave reaches the brain of pigs shot in the thigh.

The surrounding atoms, molecules, or sub-volumes experiencing the pressure wave act to constrain each other similarly to how the string constrains the cradle's balls to a straight line. For example, lithotripsy shock waves can be sent through the skin and tissue without harm to burst kidney stones. The side of the stones opposite to the incoming pressure wave bursts, not the side receiving the initial strike.

Average time until incapacitation decreases rapidly with pressure wave magnitude as magnitudes approach . See: Links between traumatic brain injury and ballistic pressure waves originating in the thoracic cavity and extremities. Brain Injury 21(7): 657–662, 2007. Hydrostatic shock is the controversial concept that a penetrating projectile (such as a bullet) can produce a pressure wave that causes "remote neural damage", "subtle damage in neural tissues" and/or "rapid incapacitating effects" in living targets.

In the arterial system, this is usually around 120 mmHg systolic (high pressure wave due to contraction of the heart) and 80 mmHg diastolic (low pressure wave). In contrast, pressures in the venous system are constant and rarely exceed 10 mmHg. Vascular resistance occurs where the vessels away from the heart oppose the flow of blood. Resistance is an accumulation of three different factors: blood viscosity, blood vessel length, and vessel radius.

The pressure wave generated by the colossal third explosion radiated out from Krakatoa at . The eruption is estimated to have reached 310 dB, loud enough to be heard away. It was so powerful that it ruptured the eardrums of sailors away on ships in the Sunda Strait, and caused a spike of more than in pressure gauges away, attached to gasometers in the Batavia gasworks, sending them off the scale. The pressure wave was recorded on barographs all over the world.

Wave rotors utilize shock waves to transfer energy between a high-energy fluid to a low-energy fluid, thereby increasing both temperature and pressure of the low-energy fluid (also called pressure wave machines or pressure exchangers).

The gun was removed and sent back to the Naval Gun Factory to be examined by a special board. Their theory was that a pressure wave had built up from the burning of older smokeless powder used.

In a study of a handgun injury, Sturtevant found that pressure waves from a bullet impact in the torso can reach the spine and that a focusing effect from concave surfaces can concentrate the pressure wave on the spinal cord producing significant injury. This is consistent with other work showing remote spinal cord injuries from ballistic impacts. Roberts et al. present both experimental work and finite element modeling showing that there can be considerable pressure wave magnitudes in the thoracic cavity for handgun projectiles stopped by a Kevlar vest.

These scientists observed neural damage in the brain caused by the distant effects of the ballistic pressure wave originating in the thigh. The results of Suneson et al. were confirmed and expanded upon by a later experiment in dogs which "confirmed that distant effect exists in the central nervous system after a high-energy missile impact to an extremity. A high-frequency oscillating pressure wave with large amplitude and short duration was found in the brain after the extremity impact of a high-energy missile ..." Wang et al.

The pressure is very non-uniform and is not adiabatic, so the pressure wave heats the sample up in passing. The conditions of the experiment must be interpreted in terms of a set of pressure-density curves called Hugoniot curves.

Although an inland eruption, the Taupo eruption is considered to have caused an atmospheric pressure wave of sufficient magnitude to cause a tsunami. Radiocarbon dating of prehistoric tsunami in the Cook Strait area indicates a possible correlation with one such event.

Alternatively, a shallow draught vessel can be steamed through the minefield at high speed to generate a pressure wave sufficient to trigger mines, with the minesweeper moving fast enough to be sufficiently clear of the pressure wave so that triggered mines do not destroy the ship itself. These techniques are the only publicly known to be employed way to sweep pressure mines. The technique can be simply countered by use of a ship-counter, set to allow a certain number of passes before the mine is actually triggered. Modern doctrine calls for ground mines to be hunted rather than swept.

Energy exchange in the pressure-wave supercharger occurs at sound velocity, resulting in good response even at low engine speeds, a common downfall of turbocharged engines. It combines the advantages of mechanical and exhaust gas supercharging, offering ample torque at lower engine speeds.

The standard example of a longitudinal wave is a sound wave or "pressure wave" in gases, liquids, or solids, whose oscillations cause compression and expansion of the material through which the wave is propagating. Pressure waves are called "primary waves", or "P-waves" in geophysics.

Michael F. O'Rourke credits Millar with the development of an applanation tonometer with the accuracy to record pulse pressure wave fluctuations when the surface of an artery is flattened. These catheter-tipped manometers made possible depiction of the changes in pulse pressure waveforms with age.

The pressure wave from an underground explosion will propagate through the ground and cause a minor earthquake. Theory suggests that a nuclear explosion could trigger fault rupture and cause a major quake at distances within a few tens of kilometers from the shot point.

Exhaust system for a motor scooter with an expansion chamber in the middle section (inlet is shown at the top right of the picture and muffler/outlet is above the expansion chamber). In two-stroke engines where the exhaust port is opened by being uncovered by the piston (rather than by a separate valve), a tuned exhaust system usually consists of an expansion chamber. The expansion chamber is designed to produce a negative pressure wave to assist in filling the cylinder with the next intake charge, and then to produce a positive pressure wave which reduces the amount of fresh intake charge that escapes through the exhaust port (port blocking).

Effect of a pressure surge on a float gauge Hydraulic shock (colloquial: water hammer; fluid hammer) is a pressure surge or wave caused when a fluid, usually a liquid but sometimes also a gas, in motion is forced to stop or change direction suddenly; a momentum change. This phenomenon commonly occurs when a valve closes suddenly at an end of a pipeline system, and a pressure wave propagates in the pipe. This pressure wave can cause major problems, from noise and vibration to pipe rupture or collapse. It is possible to reduce the effects of the water hammer pulses with accumulators, expansion tanks, surge tanks, blowoff valves, and other features.

In four milliseconds, the heat generated by the resulting enormous power excursion caused fuel inside the core to melt and to explosively vaporize. The expanding fuel produced an extreme pressure wave that blasted water upward, striking the top of the reactor vessel with a peak pressure of .

The picture at right shows the effects of a nuclear-bomb-generated 5 psi pressure wave on a test structure in Nevada in 1953. A major effect of this kind of structural damage was that it created fuel for fires that were started simultaneously throughout the severe destruction region.

Each runner is effectively a velocity stack which reflects a positive pressure wave back down the inlet runner to maximise cylinder filling with fuel/air mix. The rpm band over which the pressure wave arrives at the open inlet valves and is able to assist in the cylinder filling is set by the length of the runner and is a relatively narrow. Swapping between runners of differing length broadens the rpm band over which benefits of the tuned inlet runners are achieved, leading to a flatter torque curve and consequently more power across the rev range. In addition air-flow within the stock intake tubing between the throttle plate and airbox has also been maximised.

Pressure waves generated by the heart in systole move the arterial walls. Forward movement of blood occurs when the boundaries are pliable and compliant. These properties form enough to create a palpable pressure wave. The heart rate may be greater or lesser than the pulse rate depending upon physiologic demand.

The wave method is based on the physically accurate concept that transient pipe flow occurs as a result of pressure waves generated and propagated from a disturbance in the pipe system (valve closure, pump trip, etc.) This method was developed and first described by Don J. Wood in 1966. A pressure wave, which represents a rapid pressure and associated flow change, travels at sonic velocity for the liquid pipe medium, and the wave is partially transmitted and reflected at all discontinuities in the pipe system (pipe junctions, pumps, open or closed ends, surge tanks, etc.) A pressure wave can also be modified by pipe wall resistance. This description is one that closely represents the actual mechanism of transient pipe flow.

Further along the exhaust pipe, the exhaust pressure wave encounters a converging conical section, and this reflects a positive pressure wave back up the pipe. This wave is timed to arrive at the exhaust port after scavenging is completed, thereby "plugging" the exhaust port to prevent spillage of fresh charge, and indeed may also push back into the cylinder any charge which has already spilled. Since the timing of this process is determined mainly by exhaust system geometry, which is extremely difficult to make variable, correct timing and therefore optimum engine efficiency can typically only be achieved over a small part of the engine's range of operating speed. For an extremely detailed description of these phenomena see Design and Simulation of Two-Stroke Engines (1996), by Prof.

The pressure wave from a blast can cause severe damage to the lungs, eardrums and cause trauma in other body areas. The design of the suit is such that both sets of ballistic panels limit the effects of the overpressure on the body while the collar completely encloses the neck area and overlaps the helmet.

This falls within the domain of physical acoustics. In fluids, sound propagates primarily as a pressure wave. In solids, mechanical waves can take many forms including longitudinal waves, transverse waves and surface waves. Acoustics looks first at the pressure levels and frequencies in the sound wave and how the wave interacts with the environment.

Investigation Report - Refinery Fire and Explosion and Fire. BP Texas City March 23, 2005, para 2.5.13 Ignition Source, p66 The blast pressure wave struck the contractor trailers, completely destroying or severely damaging many of them. The explosion sent debris flying, instantly killing 15 people in and around the trailers and severely injuring 180 others.

Elastin serves an important function in arteries as a medium for pressure wave propagation to help blood flow and is particularly abundant in large elastic blood vessels such as the aorta. Elastin is also very important in the lungs, elastic ligaments, elastic cartilage, the skin, and the bladder. It is present in all vertebrates above the jawless fish.

Difference between Shock Pulse and Vibration Consider a metal ball hitting a metal bar. At the moment of impact, a pressure wave spreads through the material of both bodies (1). The wave is transient (quickly damps out). When the wave front hits the shock pulse transducer, it will cause a dampened oscillation of the transducer's reference mass.

Chamberlin FT, Gun Shot Wounds, in Handbook for Shooters and Reloaders, Vol. II, Ackley PO, ed., Plaza Publishing, Salt Lake City, Utah, 1966. He avoided the ambiguous use of the term "shock" because it can refer to either a specific kind of pressure wave associated with explosions and supersonic projectiles or to a medical condition in the body. Col.

Magnetic fields: Magnetic bars of millimeter-scale are embedded in poly(vinyl alcohol). The magnetic field within the bars is alternated, which results in the change of shape and ultimate collapse of the nanocapsules. The change in the structure then triggers the drug release. Ultrasound: Another option of drug release is through ultrasound, which is a “longitudinal pressure wave”.

On 4 August 2020, a warehouse containing of ammonium nitrate exploded following a fire in the Port of Beirut, Lebanon. The explosion generated a pressure wave felt more than away. Following early estimates of the yield of the explosion ranging from hundreds of tons of TNT equivalentbeirut-explosion-ammonium- nitrate www.washingtonpost.com'The bags say "NITROPRILL HD,"...' twitter.

The pressure wave was so powerful it blew out windows off site up to away. An area estimated at of the refinery was badly burned by the subsequent fire that followed the violent explosion, damaging millions of dollars worth of refinery equipment.U.S. Chemical Safety and Hazard Investigation Board. Investigation Report — Refinery Fire and Explosion and Fire.

Typical pressure wave caused by closing a valve in a pipeline One of the first to successfully investigate the water hammer problem was the Italian engineer Lorenzo Allievi. Water hammer can be analyzed by two different approaches—rigid column theory, which ignores compressibility of the fluid and elasticity of the walls of the pipe, or by a full analysis that includes elasticity. When the time it takes a valve to close is long compared to the propagation time for a pressure wave to travel the length of the pipe, then rigid column theory is appropriate; otherwise considering elasticity may be necessary. Below are two approximations for the peak pressure, one that considers elasticity, but assumes the valve closes instantaneously, and a second that neglects elasticity but includes a finite time for the valve to close.

No reflection will occur. A high impedance load (e.g. by plugging the end of the line) will cause a reflected wave in which the direction of the pressure wave is reversed but the sign of the pressure remains the same. Since a transmission line behaves like a four terminal model, one cannot really define or measure the impedance of a transmission line component.

ANFO, show reduced sensitivity under pressure. A transient pressure wave from a nearby detonation may compress the explosive sufficiently to make its initiation fail. This can be prevented by introducing sufficient delays into the firing sequence. A sympathetic detonation during mine blasting may influence the seismic signature of the blast, by boosting the P-wave amplitude without significantly amplifying the surface wave.

When they spread their antennae, they can sense the pressure wave from an approaching fish and jump with great speed over a few centimetres. If copepod concentrations reach high levels, schooling herrings adopt a method called ram feeding. In the photo below, herring ram feed on a school of copepods. They swim with their mouths wide open and their perculae fully expanded.

An explosive blast and explosive decompression create a pressure wave that can induce barotrauma. The difference in pressure between internal organs and the outer surface of the body causes injuries to internal organs that contain gas, such as the lungs, gastrointestinal tract, and ear. Lung injuries can also occur during rapid decompression, although the risk of injury is lower than with explosive decompression.

In this model, a traveling pressure wave would act upon the vasculature via shear stress to rearrange branches into the lowest-energy configuration by widening vessels carrying increased blood flow and rearranging networks upon the initiation of fluid flow.Koller, A. and Kaley, G. (1996). Shear stress dependent regulation of vascular resistance in health and disease: Role of endothelium. Endothelium 4: 247 – 272.

When they spread their antennae they can sense the pressure wave from an approaching fish and jump with great speed over a few centimeters. Herrings are pelagic feeders. Their prey consists of a wide spectrum of phytoplankton and zooplankton, amongst which copepods are the dominant prey. Young herring usually capture small copepods by hunting them individually— they approach them from below.

In the animation, juvenile herring hunt the copepods in synchronization: The copepods sense with their antennae the pressure-wave of an approaching herring and react with a fast escape jump. The length of the jump is fairly constant. The fish align themselves in a grid with this characteristic jump length. A copepod can dart about 80 times before it tires out.

On 13 November, a new pressure wave swept through the pack ice. The forward topgallant mast and topmasts collapsed as the bow was finally crushed. These moments were recorded on film by expedition photographer Frank Hurley. The mainmast was split near its base and shortly afterwards the mainmast and the mizzen mast broke and collapsed together, with this also filmed by Hurley.

This can only be prevented if the pressure at the exhaust port is greater than that in the cylinder. These conflicting requirements are reconciled by constructing the exhaust pipe with diverging and converging conical sections to create pressure wave reflections which travel back up the pipe and are presented at the exhaust port. The exhaust port opens while there is still significant pressure in the cylinder, which drives the initial outflow of exhaust. As the pressure wave from the pulse of exhaust gas travels down the pipe, it encounters a diverging conical section; this causes a wave of negative pressure to be reflected back up the pipe, which arrives at the exhaust port towards the end of the exhaust phase, when the cylinder pressure has fallen to a low level, and helps to draw the remaining exhaust gas out of the cylinder.

Audio amplifier Audio electronics is the implementation of electronic circuit designs to perform conversions of sound/pressure wave signals to electrical signals, or vice versa. Electronic circuits considered a part of audio electronics may also be designed to achieve certain signal processing operations, in order to make particular alterations to the signal while it is in the electrical form.Kadis, J. (2011). Introduction to sound recording technology.

Cannon A waves, or cannon atrial waves, are waves seen occasionally in the jugular vein of humans with certain cardiac arrhythmias. When the atria and ventricles contract simultaneously, the blood will be pushed against the AV valve, and a very large pressure wave runs up the vein. It is associated with heart block, in particular third-degree (complete) heart block. It is also seen in pulmonary hypertension.

The pattern formed a triangle about 40 yards (37 m) on a side at a distance of 275 yards (250 m) ahead of the ship. Most Squid installations utilised two sets of mortars. All six bombs were fired in salvo so they formed opposing triangular spreads. The salvos were set to explode above and below the target, the resulting pressure wave crushing the hull of the submarine.

Reports following a reading on AWDREY were prefixed with the codewords "Tocsin Bang". Bomb Power Indicator with ‘Kilopascal’ overlay. This was added in the 1970s to cover the original P.S.I scale which had been superseded. The Bomb Power Indicator or BPI consisted of a peak overpressure gauge with a dial that would register when the pressure wave from a nuclear explosion passed over the post.

A contemporary photograph of the explosion that destroyed Invincible shows flame and smoke erupting from 'X' turret. Coupled with the aft turret's missing roof, it implies that 'X' magazine also caused a low-order explosion within the ship.A low-order explosion describes an explosive event where the blast pressure wave moves slowly forward displacing or wrenching (rather than shattering) objects in its path.Brown, p.

The very dark area on the northeast side of the crater is probably covered by smooth material such as fine-grained sediment. This dark halo is asymmetric, mimicking the asymmetric shape of the ejecta blanket. The dark halo may have been caused by an atmospheric shock or pressure wave produced by the incoming body. Jeanne crater also displays several outflow lobes on the northwest side.

Schlieren photograph of an attached shock on a sharp-nosed supersonic body. The Mach angle is acute, showing that the body exceeds Mach 1. The angle of the Mach wave (~59 degrees) indicates a velocity of about Mach 1.17. In fluid dynamics, a Mach wave is a pressure wave traveling with the speed of sound caused by a slight change of pressure added to a compressible flow.

The roof of the silo was blown off by the pressure wave, the walls collapsed, and the whole building was torn apart. Windows were broken in houses even a large distance away from the mill, and flour dust rained down across an area of about 30 hectares. 14 people died in the detonation, and 17 were seriously injured. The fire burned until 12 March 1979.

The two remaining employees were initially reported as missing, later in the day it became clear they had been killed by the explosion. In a radius of approximately 5 kilometres surrounding the fireworks factory, window panes shattered or trembled dangerously. The air pressure wave was so powerful that cars driving by on the A2 motorway 100 metres away were almost blown off the road.

Today's understanding of exhaust systems and fluid dynamics has given rise to a number of mechanical improvements. One such improvement can be seen in the exhaust ultimate power valve ("EXUP") fitted to some Yamaha motorcycles. It constantly adjusts the back pressure within the collector of the exhaust system to enhance pressure wave formation as a function of engine speed. This ensures good low to mid-range performance.

US4563997 Fig1 Pressure wave supercharger A pressure wave supercharger (also known as a wave rotorWhat is a Wave Rotor) is a type of supercharger technology that harnesses the pressure waves produced by an internal combustion engine exhaust gas pulses to compress the intake air. Its automotive use is not widespread; the most widely used example is the Comprex, developed by Brown Boveri., issued 1988-10-19, assigned to BBC Brown Boveri AG, Baden, Switzerland, issued 1989-07-13, assigned to BBC Brown Boveri AG, Baden, SwitzerlandA Review of Wave Rotor Technology and its Applications including details of Comprex supercharger Valmet Tractors of Finland were one of the first to use the device when they fitted it to the 411CX engine which powered their 1203 model of 1980. Although it provided a useful increase in performance it was considered too expensive to be incorporated into later models.

Note how the suction wave during cylinder filling is delayed even more by having to fight upstream against the inrushing air and the fact that the piston is further down the bore, increasing the distance. The goal of tuning is to arrange the runners and valve timing so that there is a high-pressure wave in the port during the opening of the intake valve to get flow going quickly and then to have a second high pressure wave arrive just before valve closing so the cylinder fills as much as possible. The first wave is what is left in the runner from the previous cycle, while the second is primarily created during the current cycle by the suction wave changing sign at the runner entrance and arriving back at the valve in time for valve closing. The factors involved are often contradictory and requires a careful balancing act to work.

The 4 cycles of operation of the Pressure Wave Supercharger. The process is controlled by a cylindrical cell rotor driven by the engine crankshaft via a belt or chain. Individual cells alternately open and close the exhaust gas and fresh air apertures. When the aperture on the exhaust gas side is reached, pressurized exhaust gas flows into the cell and compresses the fresh air there (Diagram Stage 2).

37 (2012) 3423-3425. At least some of the electromagnetic energy absorbed by the sample is converted to heat; the resulting temperature rise, on the order of milli-Kelvins, leads to thermo- elastic expansion of the sample. This creates a pressure wave in the form of a broadband ultrasound wave. The ultrasound waves emitted by the sample are detected by transducers positioned near the sample, usually at multiple positions around it.

Gulfstream also designed and developed a means of reducing the sonic boom caused by an aircraft "breaking" the sound barrier – the Quiet Spike. The Quiet Spike is a telescopic nose device that softens the effect of the sonic boom by smoothing the pressure wave created by flying at the speed of sound. Gulfstream views lifting the current US supersonic ban as essential for a viable business case for supersonic aircraft.McMillin, Molly.

Telemetry is used to transmit drilling mechanics and formation evaluation information uphole, in real time, as a well is drilled. These services are known as Measurement while drilling and Logging while drilling. Information acquired thousands of feet below ground, while drilling, is sent through the drilling hole to the surface sensors and the demodulation software. The pressure wave (sana) is translated into useful information after DSP and noise filters.

When the vacuum under the window is large enough, the airstream is pulled under the Labium lip. Then the process works in reverse, with a low pressure region forming over the Labium which pulls the airstream to the other side again. This 'fluttering' airflow creates high and low pressure waves within the pipe's air column. A high and a low pressure wave form a single "cycle" of the pipe's tone.

The fish swim in a grid where the distance between them is the same as the jump length of their prey, as indicated in the animation above right. In the animation, juvenile herring hunt the copepods in this synchronised way. The copepods sense with their antennae the pressure wave of an approaching herring and react with a fast escape jump. The length of the jump is fairly constant.

The (half speed) video loop at the left shows a juvenile herring feeding on copepods. In the middle of the image a copepod escapes successfully to the left. The opercula (hard bony flaps covering the gills) are spread wide open to compensate the pressure wave which would alert the copepod to trigger a jump.Kils, U (1992) The ecoSCOPE and dynIMAGE: Microscale tools for in situ studies of predator–prey interactions.

For example, Ibolja Cernak, a leading researcher in blast wave injury at the Applied Physics Laboratory at Johns Hopkins University, hypothesized, "alterations in brain function following blast exposure are induced by kinetic energy transfer of blast overpressure via great blood vessels in abdomen and thorax to the central nervous system." This hypothesis is supported by observations of neural effects in the brain from localized blast exposure focused on the lungs in experiments in animals. "Hydrostatic shock" expresses the idea that organs can be damaged by the pressure wave in addition to damage from direct contact with the penetrating projectile. If one interprets the "shock" in the term "hydrostatic shock" to refer to the physiological effects rather than the physical wave characteristics, the question of whether the pressure waves satisfy the definition of "shock wave" is unimportant, and one can consider the weight of scientific evidence and various claims regarding the possibility of a ballistic pressure wave to create tissue damage and incapacitation in living targets.

On 23 August 1966 the ship was transferred to the United States Navy to be converted into a Minesweeper, Special by American Shipbuilding of Lorain, Ohio. The ship's hull was completely gutted and a shock-hardened pilot house was fitted. Intended to sweep influence mines by detonating them with pressure wave or magnetic signature generated by her hull. In late summer of 1969, the ship underwent extensive shock testing off Key West, Florida.

Still unfinished, the vehicle was entered in an SPL competition in 1997 at which a complaint was lodged against the computer control of the DC motor. Instead of using the controller, two leads were touched together in the hope that the motor speed was set correctly. The drive shaft broke after one positive stroke which created an interior pressure wave of 162 dB. The Concept Design 60-inch was not shown in public after 1998.

Vibrations from the oval window of the inner ear is transferred to the perilymph in the upper canal via a pressure wave. The Reissner's membrane transfers the vibrations to the endolymph of the middle canal. The Basilar membrane then vibrates and triggers the hair cells of the organ of Corti. The kinetic energy is converted to electrochemical energy as the auditory nerve transmits the information to the brain where sound is interpreted.

Pressure container with separate inlet and outlet, connectable to a pipe system so that all pressure changes must attempt to pass through said chamber. Entry and exit of said chamber being of a diameter relative to chamber diameter that provides a high discharge coefficient, and without close proximity of any reflective surface. Lack of any sudden change in cross section area of flow path that would reflect a pressure wave, i.e. no orifice plate(s).

An earthquake is caused by the release of stored elastic strain energy during rapid sliding along a fault. The sliding starts at some location and progress away from the hypocenter in each direction along the fault surface. The speed of the progression of this fault tear is slower than, and distinct from the speed of the resultant pressure and shear waves, with the pressure wave traveling faster than the shear wave. The pressure waves generate an abrupt shock.

As in all lepidosaurs and archosaurs, the single-ossicle (columellar) middle ear transmits sound to the footplate of the columella, which sends a pressure wave through the inner ear. In snakes, the basilar papilla is roughly 1mm long and only responds to frequencies below about 1 kHz. In contrast, lizards tend to have two areas of hair cells, one responding below and the other above 1 kHz. The upper frequency limit in most lizards is roughly 5–8 kHz.

This has proven successful with small caliber(.17-.22) rifles, but the amplitude has not been matched efficiently with larger cartridges. With the use of subsonic ammunition, the resultant sound waves effectively cancel out one another, and with the exception of the sound of the action cycling, completely eliminate any gunshot sound. In the current development stage, this has worked only in close proximity to the shooter, and the pressure wave(p-wave) can still be felt.

One hypothesis is that the length of the neck made it possible to surprise schools of fish, the head arriving before the sight or pressure wave of the trunk could alert them. "Plesiosauromorphs" hunted visually, as shown by their large eyes, and perhaps employed a directional sense of olfaction. Hard and soft-bodied cephalopods probably formed part of their diet. Their jaws were probably strong enough to bite through the hard shells of this prey type.

Fireball blast from the Russian "Father of All Bombs", with the beginnings of a mushroom cloud The thermobaric device yields the equivalent of 44 tons of TNT using about seven tons of a new type of high explosive. Because of this, the bomb's blast and pressure wave have a similar effect to a small tactical nuclear weapon. The bomb works by detonating in mid-air. Most damage is inflicted by a supersonic shockwave and extremely high temperatures.

Variation potentials can only be produced if the pressure in the xylem is disturbed and followed by an increase in xylem pressure. Additionally, it uses vascular bundles to complete systemic potential throughout the plant. Variation potentials are distinct from action potentials in their cause of stimulation. Depolarization arises from an increase in plant cell turgor pressure from a hydraulic pressure wave that moves through the xylem after events like rain, embolism, bending, local wounds, organ excision, and local burning.

Optoacoustic imaging in general, and MSOT in particular, have been applied to various analyses of animal models, including imaging of organs, pathology, functional processes and bio- distribution. This range of applications demonstrates the flexibility of MSOT, which reflects the range of contrast agents available. Practically every molecule that absorbs light and converts it to a pressure wave has the potential to be detected with optoacoustics. Contrast agents absorbing light in the near-IR are particularly attractive, because they enable imaging at greater depth.

At least one torpedo hit Awa Maru, and Hayasui burst into flame and sank stern first after being hit by two or three torpedoes at 0320. Rasher launched four bow torpedoes shortly after midnight at a range of , and three hits on the cargo-transport Eishin Maru caused an ammunition detonation with the pressure wave sweeping over the submarine's bridge. The fourth torpedo was heard exploding on a more distant ship. Rasher then swung hard right to launch two stern torpedoes.

The acoustic pressure wave method analyses the rarefaction waves produced when a leak occurs. When a pipeline wall breakdown occurs, fluid or gas escapes in the form of a high velocity jet. This produces negative pressure waves which propagate in both directions within the pipeline and can be detected and analyzed. The operating principles of the method are based on the very important characteristic of pressure waves to travel over long distances at the speed of sound guided by the pipeline walls.

The amplitude of a pressure wave increases with the leak size. A complex mathematical algorithm analyzes data from pressure sensors and is able in a matter of seconds to point to the location of the leakage with accuracy less than 50 m (164 ft). Experimental data has shown the method's ability to detect leaks less than 3mm (0.1 inch) in diameter and operate with the lowest false alarm rate in the industry – less than 1 false alarm per year.Avateq Corp.

Sound is a pressure wave, which consists of alternating periods of compression and rarefaction. A noise- cancellation speaker emits a sound wave with the same amplitude but with inverted phase (also known as antiphase) to the original sound. The waves combine to form a new wave, in a process called interference, and effectively cancel each other out – an effect which is called destructive interference. Modern active noise control is generally achieved through the use of analog circuits or digital signal processing.

Unlike other mechanisms of injury in which pulmonary contusion is often found alongside other injuries, explosions can cause pulmonary contusion without damage to the chest wall. In addition to blunt trauma, penetrating trauma can cause pulmonary contusion. Contusion resulting from penetration by a rapidly moving projectile usually surrounds the path along which the projectile traveled through the tissue. The pressure wave forces tissue out of the way, creating a temporary cavity; the tissue readily moves back into place, but it is damaged.

Was the source a direct observer of the event, or (if a human source) is he or she reporting hearsay? Technical sensors may directly view an event, or infer it. A geophysical infrasound sensor can record the pressure wave of an explosion, but may be unable to tell if an explosion was due to a natural event or an industrial accident. It may be able to tell that the explosion was not nuclear, since nuclear explosions are more concentrated in time.

On 14 February 1991, around 11:50, a heavy explosion occurred in an outbuilding of MS Vuurwerk. Most likely, there were actually two explosions within 20 seconds of each other, the second one much stronger than the first. An enormous air pressure wave ensued, which caused major structural and bodily damage in a vast area around it. There was also a pitch-black cloud of dust which, according to Uittenboogaard, lasted for 5 to 7 minutes and obstructed all vision.

Such explosions are known as fuel–coolant interactions (FCI). In these events the passage of the pressure wave through the predispersed material creates flow forces which further fragment the melt, resulting in rapid heat transfer, and thus sustaining the wave. Much of the physical destruction in the Chernobyl disaster, a graphite-moderated, light-water- cooled RBMK-1000 reactor, is thought to have been due to such a steam explosion. In a nuclear meltdown, the most severe outcome of a steam explosion is early containment building failure.

Officially designated as mine destructor vessels, the Cybele class was a large trimaran vessel,Preston 1987, p.139. constructed using a steel lattice truss framework. They were intended to be towed through minefields that used pressure mines, creating a pressure wave that would detonate the mines; the open lattice construction of the ships would, according to the design, allow the blast to pass through the vessel without causing damage to it. The ships were constructed under conditions of the utmost secrecy;Gardiner and Brown 2004, p.163.

When the wave reaches the end of the transmission line, its behaviour depends on what is present at the end of the line. There are three generalized scenarios: A low impedance load (e.g. leaving the end open in free air) will cause a reflected wave in which the sign of the pressure variation reverses, but the direction of the pressure wave remains the same. A load that matches the characteristic impedance (defined below) will completely absorb the wave and the energy associated with it.

Both compression-driven and blast-driven shock tubes are currently used for scientific as well as military applications. Compressed-gas driven shock tubes are more easily obtained and maintained in laboratory conditions; however, the shape of the pressure wave is different from a blast wave in some important respects and may not be suitable for some applications. Blast-driven shock tubes generate pressure waves that are more realistic to free-field blast waves. However, they require facilities and expert personnel for handling high explosives.

Nitroglycerin and any diluents can certainly deflagrate (burn). The explosive power of nitroglycerin derives from detonation: energy from the initial decomposition causes a strong pressure wave that detonates the surrounding fuel. This is a self-sustained shock wave that propagates through the explosive medium at 30 times the speed of sound as a near-instantaneous pressure-induced decomposition of the fuel into a white-hot gas. Detonation of nitroglycerin generates gases that would occupy more than 1,200 times the original volume at ordinary room temperature and pressure.

As with similar inlet cam phasing systems like BMW VANOS the phasing is returned to the retarded state at higher rpm to improve power and efficiency as inlet gas dynamics change with rpm. The short inlet ducts being tuned to the higher frequency and thus shorter inlet duct pressure wave. On 8V engines the valve overlap and intake open duration are quite big. These engines hardly idle with the variator at On position so on these models it had the meaning also to enhance lower speed operation.

In the same way a flag flaps in the breeze, the air rushing past the reed causes it to vibrate. As air pressure from the mouth increases, the amount the reed vibrates increases until the reed hits the mouthpiece. At this point, the reed stays pressed against the mouthpiece until either the springiness of the reed forces it to open or a returning pressure wave 'bumps' into the reed and opens it. Each time the reed opens, a puff of air goes through the gap, after which the reed swings shut again.

These receptors also cause a renal vasodilation, resulting in increase of the water amount in the glomerular filtrate which, combined with the increased production of vasopressin by the hypothalamus, will cause water retention in urine. This increases the blood volume, resulting in the increase of blood pressure. There are two types, type A is activated by atrial wall tension in atrial contraction (during the a wave of the atrial pressure curve), type B is activated by atrial stretch during atrial filling (with the v pressure wave). They can display hysteresis.

The pressure wave from the third and most violent explosion was recorded on barographs around the world. Several barographs recorded the wave seven times over the course of five days: four times with the wave travelling away from the volcano to its antipodal point, and three times travelling back to the volcano; the wave rounded the globe three and a half times. Ash was propelled to a height of . The sound of the eruption was so loud it was reported that if anyone was within , they would have gone deaf.

In arguments about the differences in stopping power between calibers and between cartridge models, proponents of cartridges that are "light and fast" (such as the 9×19mm Parabellum) versus cartridges that are "slow and heavy" (such as the .45 ACP) often refer to this phenomenon. Martin Fackler has argued that sonic pressure waves do not cause tissue disruption and that temporary cavity formation is the actual cause of tissue disruption mistakenly ascribed to sonic pressure waves. One review noted that strong opinion divided papers on whether the pressure wave contributes to wound injury.

Ballistic pressure waves believed to be the mechanism of hydrostatic shock that were measured with a high speed pressure transducer for the specified loads. A shock wave can be created when fluid is rapidly displaced by an explosive or projectile. Tissue behaves similarly enough to water that a sonic pressure wave can be created by a bullet impact, generating pressures in excess of . Duncan MacPherson, a former member of the International Wound Ballistics Association and author of the book, Bullet Penetration, claimed that shock waves cannot result from bullet impacts with tissue.

Partnair suggested said that the F-16 fighter jet had been flying at a faster velocity and closer to the Convair than reported in the media. Therefore, the jet, which would have broken the supersonic barrier at that point, would have created a supersonic pressure wave that would have caused the Convair to disintegrate in mid-air. The National Aeronautical Research Institute, a Swedish aviation technology research facility, said that there was a 60% chance of this being the cause. The Norwegian F-16 pilot testified that his aircraft was more than above the Convair.

This graph shows the pressure taken from the valve end (blue line) and the runner entrance(red line) of an engine with a port/runner and running at 4500 rpm. Highlighted are two waves, a suction wave and a valve closing wave, seen and the valve end and runner entrance showing the signal delay. A lag of about 85 deg for the peak suction wave versus about 32 deg for the peak pressure wave. A difference of some 53 deg due to the movement of the gas and piston position.

The other failure mode is a deflagration to detonation transition; the supersonic pressure wave formed in the combustion chamber may destroy the engine. Combustion instability was also a problem during Atlas development. The Rocketdyne engines used in the Atlas family were found to suffer from this effect in several static firing tests, and three missile launches exploded on the pad due to rough combustion in the booster engines. In most cases, it occurred while attempting to start the engines with a "dry start" method whereby the igniter mechanism would be activated prior to propellant injection.

At the midpoint of an oscillation the hair bundles resume their resting position. When the basilar membrane moves downward, the hair bundles are driven in the inhibitory direction. Basilar Membrane motion causes a shearing motion between the reticular lamina and the tectorial membrane, thereby activating the mechano-sensory apparatus of the hair bundle, which in turn generates a receptor potential in the hair cells. Thus the sound pressure wave is transduced to an electrical signal which can be processed as sound in higher parts of the auditory system.

The armament was based around two Limbo Mark 10 anti-submarine mortars. This allowed a three-bomb salvo to be placed both above and below the target, creating a convergent pressure wave more likely to assure a kill. The Limbos were mounted in a well on the quarterdeck, with a 360° arc of fire. Again, wartime experience had shown that the quarterdeck, perhaps not an obvious location for an ahead throwing weapon, was indeed the best location for such weapons where they were out of the spray towards the front of the vessel.

Anderson, J. D., 1989, 'Hypersonic and High Temperature Gas Dynamics', AIAA. Shock tubes have been developed in a wide range of sizes. The size and method of producing the shock wave determine the peak and duration of the pressure wave it produces. Thus, shock tubes can be used as a tool used to both create and direct blast waves at a sensor or an object in order to imitate actual explosions and the damage that they cause on a smaller scale, provided that such explosions do not involve elevated temperatures and shrapnel or flying debris.

Once the exhaust pressure has fallen to near-atmospheric level, the piston uncovers the transfer ports. At this point energy from the expansion chamber can be used to aid the flow of fresh mixture into the cylinder. To do this, the expansion chamber is increased in diameter so that the out-going acoustic wave (created by the combustion process) creates a reflected vacuum (negative pressure) wave that returns to the cylinder. This part of the chamber is called the divergent (or diffuser) section and it diverges at 7 to 9 degrees.

Photoacoustic spectroscopy is the measurement of the effect of absorbed electromagnetic energy (particularly of light) on matter by means of acoustic detection. The discovery of the photoacoustic effect dates to 1880 when Alexander Graham Bell showed that thin discs emitted sound when exposed to a beam of sunlight that was rapidly interrupted with a rotating slotted disk. The absorbed energy from the light causes local heating, generating a thermal expansion which creates a pressure wave or sound. Later Bell showed that materials exposed to the non-visible portions of the solar spectrum (i.e.

The ice began "working", with sounds of breaking and colliding ice audible to those on the ship through the next day. Breaks in the ice were spotted but none approached the ice holding the Endurance. During July the ship drifted a further to the north. On the morning of 1 August, a pressure wave passed through the floe holding the ship, lifting the 400-ton Endurance bodily upwards and heeling the ship sharply to its port side before it dropped into a pool of water, afloat again for the first time in nearly six months.

The forces in the Hertzian solution above were assumed to propagate in the balls immediately, which is not the case. Sudden changes in the force between the atoms of material build up to form a pressure wave. Pressure waves (sound) in steel travel about 5 cm in 10 microseconds, which is about 10 times faster than the time between the first ball striking and the last ball being ejected. The pressure waves reflect back and forth through all five balls about ten times, although dispersing to less of a wavefront with more reflections.

437–456, 1914. as a way to measure stress pulse propagation in a metal bar. Later, in 1949 Herbert Kolsky refined Hopkinson's technique by using two Hopkinson bars in series, now known as the split-Hopkinson bar, to measure stress and strain, incorporating advancements in the cathode ray oscilloscope in conjunction with electrical condenser units to record the pressure wave propagation in the pressure bars as pioneered by Rhisiart Morgan Davies a year earlier in 1948.RM Davies, "A critical study of the Hopkinson Pressure Bar" Philos. Trans.

US practice is to fit both at the regulator. The flashback arrestor prevents shock waves from downstream coming back up the hoses and entering the cylinder, possibly rupturing it, as there are quantities of fuel/oxygen mixtures inside parts of the equipment (specifically within the mixer and blowpipe/nozzle) that may explode if the equipment is incorrectly shut down, and acetylene decomposes at excessive pressures or temperatures. In case the pressure wave has created a leak downstream of the flashback arrestor, it will remain switched off until someone resets it.

Three torpedoes hit and sank the 20,000 ton carrier , which was escorting the convoy, and the fourth torpedo was heard exploding on a more distant ship. Rasher pulled away to reload torpedo tubes and the convoy split into two groups. Rasher followed the group moving northwest while Bluefish intercepted the remaining ships continuing southwesterly and sank two tankers. Rasher launched four bow torpedoes at a range of , and three hits on the cargo- transport Eishin Maru caused an ammunition detonation with the pressure wave sweeping over the submarine's bridge.

The effect can be used to produce acoustic oscillations by supplying heat to the hot side of a stack, and sound oscillations can be used to induce a refrigeration effect by supplying a pressure wave inside a resonator where a stack is located. In a thermoacoustic prime mover, a high temperature gradient along a tube where a gas media is contained induces density variations. Such variations in a constant volume of matter force changes in pressure. The cycle of thermoacoustic oscillation is a combination of heat transfer and pressure changes in a sinusoidal pattern.

When an explosion happens in an enclosed space, water hammer can cause the walls of the container to deform. However, it can also impart momentum to the enclosure if it is free to move. An underwater explosion in the SL-1 nuclear reactor vessel caused the water to accelerate upwards through of air before it struck the vessel head at with a pressure of . This pressure wave caused the steel vessel to jump 9 feet 1 inch (2.77 m) into the air before it dropped into its prior location.

A transducer made of a piezoelectric diaphragm being disturbed by a sound pressure wave. A vibration powered generator is a type of electric generator that converts the kinetic energy from vibration into electrical energy. The vibration may be from sound pressure waves or other ambient Vibration powered generators usually consist of a resonator which is used to amplify the vibration source, and a transducer mechanism which converts the energy from the vibrations into electrical energy. The transducer usually consists of a magnet and coil or a piezoelectric crystal.

Silky sharks frequently intermingle with schools of scalloped hammerheads (Sphyrna lewini), and have been known to follow marine mammals. One account from the Red Sea describes 25 silky sharks following a large pod of bottlenose dolphins (Tursiops sp.), along with 25 grey reef sharks (C. amblyrhynchos) and a lone silvertip shark (C. albimarginatus). Silky sharks are themselves accompanied by juvenile pilot fish (Naucrates ductor), which "ride" the pressure wave ahead of the shark, as well as by jacks, which snatch scraps of food and rub against the shark's skin to scrape off parasites.

Melted and fused pieces of metal (including coins that were in people's pockets) from the Atomic bombings of Japan. The melting of metal like this occurred during the ensuing fires and firestorms, long after the bombs had exploded. The main causes of death and disablement in this state are thermal burns and the failure of structures resulting from the blast effect. Injury from the pressure wave is minimal in contrast because the human body can survive up to 2 bar (30 psi) while most buildings can withstand only a 0.8 bar (12 psi) blast.

If a steam explosion occurs in a confined tank of water due to rapid heating of the water, the pressure wave and rapidly expanding steam can cause severe water hammer. This was the mechanism that, in Idaho, USA, in 1961, caused the SL-1 nuclear reactor vessel to jump over in the air when it was destroyed by a criticality accident. In the case of SL-1, the fuel and fuel elements vaporized from instantaneous overheating. Events of this general type are also possible if the fuel and fuel elements of a liquid-cooled nuclear reactor gradually melt.

Depiction of photoacoustic tomography Deep learning in photoacoustic imaging combines the hybrid imaging modality of photoacoustic imaging (PA) with the rapidly evolving field of deep learning. Photoacoustic imaging is based on the photoacoustic effect, in which optical absorption causes a rise in temperature, which causes a subsequent rise in pressure via thermo-elastic expansion. This pressure rise propagates through the tissue and is sensed via ultrasonic transducers. Due to the proportionality between the optical absorption, the rise in temperature, and the rise in pressure, the ultrasound pressure wave signal can be used to quantify the original optical energy deposition within the tissue.

15, p. 328 The Confederate submarine escaped but was lost with all hands not long after this action; new evidence announced by archaeologists in 2013 indicates that the submarine may have been much closer to the point of detonation than previously realized, thus damaging the submarine as well.Brian Hicks, Hunley legend altered by new discovery, The Post and Courier, 28 January 2013, accessed 28 January 2013. In 2017, researchers at Duke University further established through simulation that the Hunley's crew were most likely killed immediately at their posts by the blast's pressure wave damaging their lungs and brains.

Sound, which propagates as a pressure wave, can be induced in virtually any material, including biologic tissue, whenever time-varying electromagnetic energy is absorbed. The stimulating radiation that induces these thermally generated acoustic waves may lie anywhere in the electromagnetic spectrum, from high- energy ionizing particles to low-energy radio waves. The term "photoacoustic" (see photoacoustic imaging in biomedicine) applies to this phenomenon when the stimulating radiation is optical, while "thermoacoustic" is the more general term and refers to all radiating sources, including optical. The process by which thermoacoustic waves are generated is depicted in the Figure 3.

One such mechanism is the opening of ion channels in the hair cells of the cochlea in the inner ear. Air pressure changes in the ear canal cause the vibrations of the tympanic membrane and middle ear ossicles. At the end of the ossicular chain, movement of the stapes footplate within the oval window of the cochlea, in turn, generates a pressure field within the cochlear fluids, imparting a pressure differential across the basilar membrane. A sinusoidal pressure wave results in localized vibrations of the organ of Corti: near the base for high frequencies, near the apex for low frequencies.

Traditional sampling methods like nets have proved to be inadequate because they scare off creatures due to the pressure wave formed by the towed net and the light produced by the bioluminescent species caught in the net. Mesopelagic activity was first investigated by use of sonar because the return bounces off of plankton and fish in the water. However, there are many challenges with acoustic survey methods and previous research has estimated errors in measured amounts of biomass of up to three orders of magnitude. This is due to inaccurate incorporation of depth, species size distribution, and acoustic properties of the species.

The magnitude of damage due to the blast wave is dependent on the peak of the initial positive pressure wave, the duration of the overpressure, the medium in which it explodes, the distance from the incident blast wave, and the degree of focusing due to a confined area or walls. For example, explosions near or within hard solid surfaces become amplified two to nine times due to shock wave reflection. As a result, individuals between the blast and a building generally suffer two to three times the degree of injury compared to those in open spaces.

At the site of the destroyed dam, Carrasco finds that the Government forces have already built a pontoon bridge and are recovering the sunken supply convoy. Using scuba diving equipment, Carrasco and Smithy plant time bombs on some of the still submerged trucks that carried explosives. But the two rebels can exit the river the bombs explode, the pressure wave knocks Smithy unconscious and he surfaces and is captured. Carrasco is more fortunate and escapes with the help of an elderly friend (Pigozzi) and his men, who turn up in a truck in the nick of time.

About 80 percent of all buildings in Oppau were destroyed, leaving 6,500 homeless. The pressure wave caused great damage in Mannheim, located just across the Rhine, ripped roofs off up to 25 km away, and destroyed windows farther away, including all the medieval stained-glass windows of Worms cathedral, to the north. In Heidelberg ( from Oppau), traffic was stopped by the mass of broken glass on the streets, a tram was derailed, and some roofs were destroyed. Five hundred bodies were recovered within the first 48 hours, with the final death toll recorded being in excess of 560 people.

This theory is based on the fact that, during galloping, the absence of any bone attachment of the forelegs to the spine in the horse causes the shoulder to compress the cranial rib cage. The compression of the chest initiates a pressure wave of compression and expansion which spreads outwards. However, due to the shape of the lung and reflections off the chest wall, the wave of expansion and compression becomes focussed and amplified in the dorso-caudal lung. The alternate expansion and compression at the microscopic level in adjacent areas of lung tissue creates shear stress and capillary disruption.

Pressure Recording Analytical Method (PRAM), estimates Q from the analysis of the pressure wave profile obtained from an arterial catheter—radial or femoral access. This PP waveform can then be used to determine Q. As the waveform is sampled at 1000 Hz, the detected pressure curve can be measured to calculate the actual beat-to-beat stroke volume. Unlike FloTrac, neither constant values of impedance from external calibration, nor form pre-estimated in vivo or in vitro data, are needed. PRAM has been validated against the considered gold standard methods in stable condition and in various haemodynamic states.

In the reproduction of sound by headphones or loudspeakers, absolute phase refers the phase of the reproduced signal relative to the original signal, retaining the original polarity. A positive pressure on the microphone is reproduced as a positive pressure by the loudspeaker or headphones driver. For instance, the plosive "p" sound from a vocalist sends an initial positive air pressure wave toward the microphone which responds with an initial inward movement of the microphone diaphragm, away from the vocalist. To maintain absolute phase, a loudspeaker reproducing the sound would send an initial positive pressure outward from the loudspeaker, toward the listener.

The intake tube takes in air and mixes it with fuel to combust, and also controls the expulsion of exhaust gas, like a valve, limiting the flow but not stopping it altogether. While the fuel-air mixture burns, most of the expanding gas is forced out of the exhaust pipe of the engine. Because the intake tube(s) also expel gas during the exhaust cycle of the engine, most valveless engines have the intakes facing backwards so that the thrust created adds to the overall thrust, rather than reducing it. The combustion creates two pressure wave fronts, one traveling down the longer exhaust tube and one down the short intake tube.

Deadly fighting skills of the world, Steve Crawford (1999) pp. 68–69AK-47: the weapon that changed the face of the war, Larry Kahaner, John Wiley and Sons (2007) p. 32 It has also been suggested that pressure wave effects can cause indirect bone fractures at a distance from the projectile path, although it was later demonstrated that indirect bone fractures are caused by temporary cavity effects (strain placed on the bone by the radial tissue displacement produced by the temporary cavity formation). Proponents of the concept argue that hydrostatic shock can produce remote neural damage and produce incapacitation more quickly than blood loss effects.

An early mention of "hydrostatic shock" appeared in Popular Mechanics in April 1942. In the scientific literature, the first discussion of pressure waves created when a bullet hits a living target is presented by E. Harvey Newton and his research group at Princeton University in 1947: Frank Chamberlin, a World War II trauma surgeon and ballistics researcher, noted remote pressure wave effects. Col. Chamberlin described what he called "explosive effects" and "hydraulic reaction" of bullets in tissue. ...liquids are put in motion by 'shock waves' or hydraulic effects... with liquid filled tissues, the effects and destruction of tissues extend in all directions far beyond the wound axis.

Consequently, the ahead-looking ASDIC (sonar) set lost contact at the vital moment before the weapons were launched, allowing a skilled submarine commander to take successful evasive action. Squid, however, lobbed three , 390 pound warheads up to ahead of the launching vessel falling in a triangular pattern with sides of . As the clockwork fuses detonated the warheads at a depth determined by the ships' ASDIC set, the Squid therefore attacked in full ASDIC contact for greater accuracy and lethality. Two mortars were carried, with the bombs set to explode at different depths in order to create a convergent pressure wave to crush the hull of a submarine.

The Batavia Queen finds the mission school in ruins and ablaze because of Krakatoa's eruption; although Krakatoa's eruption was audible in Palembang and the air pressure wave from its final explosion was strong enough to shake the walls of houses and cause cracks to appear in some, the town did not suffer the serious damage implied by the condition of the mission school in the film.Anonymous, Nature: A Weekly Illustrated Journal of Science, Volume XXX, May 1884 to October 1884, New York: McMillan and Company, 1884, p. 12.Symons, G. J., ed., The Eruption of Krakatoa: And Subsequent Phenomena, London: Harrison and Sons, 1888, p. 88.

Evolution of carrier mobility in organic field-effect transistor. The carrier transport in OFET is specific for two-dimensional (2D) carrier propagation through the device. Various experimental techniques were used for this study, such as Haynes - Shockley experiment on the transit times of injected carriers, time- of-flight (TOF) experiment for the determination of carrier mobility, pressure-wave propagation experiment for probing electric-field distribution in insulators, organic monolayer experiment for probing orientational dipolar changes, optical time-resolved second harmonic generation (TRM-SHG), etc. Whereas carriers propagate through polycrystalline OFETs in a diffusion-like (trap-limited) manner, they move through the conduction band in the best single-crystalline OFETs.

Typical diesel engine noise of a 1950s direct injected two- cylinder diesel engine (MWM AKD 112 Z, in idle) The distinctive noise of a diesel engine is variably called diesel clatter, diesel nailing, or diesel knock. Diesel clatter is caused largely by the way the fuel ignites; the sudden ignition of the diesel fuel when injected into the combustion chamber causes a pressure wave, resulting in an audible ″knock″. Engine designers can reduce diesel clatter through: indirect injection; pilot or pre-injection; injection timing; injection rate; compression ratio; turbo boost; and exhaust gas recirculation (EGR). Common rail diesel injection systems permit multiple injection events as an aid to noise reduction.

A major advantage to this method is that it can be tailored towards a wide range of excitation frequencies. The natural frequency of the water droplet is a function of its size; therefore changing the size of the water droplet allows for the matching of the natural frequency of the droplet and the frequency of the pressure wave being converted into electrical energy. Matching these frequencies produces the largest amplitude oscillation of the water droplet, resulting in a large force and larger strain on the piezoelectric beam. Another application seeks to use the vibrations created during flight in aircraft to power the electronics on the plane that currently rely on batteries.

The blast from a nuclear bomb is the result of X-ray-heated air (the fireball) sending a shock wave or pressure wave in all directions, initially at a velocity greater than the speed of sound, analogous to thunder generated by lightning. Knowledge about urban blast destruction is based largely on studies of Little Boy at Hiroshima. Nagasaki buildings suffered similar damage at similar distances, but the Nagasaki bomb detonated from the city center over hilly terrain that was partially bare of buildings. psi overpressure In Hiroshima almost everything within of the point directly under the explosion was completely destroyed, except for about 50 heavily reinforced, earthquake-resistant concrete buildings, only the shells of which remained standing.

This version uses a saltwater countermass in the rear of the launcher to absorb the back blast; the resulting spray captures and dramatically slows down the pressure wave, allowing troops to fire from enclosed areas. The AT4-CS version also reduced its muzzle velocity from the original 290 m/s to 220 m/s as part of its effort to be user-safe in a confined space, making the AT4-CS version more difficult to use as the drop is more pronounced. The effectiveness of the HEAT warhead is not dependent on speed. To fire, the gunner first removes the safety pin located at the rear of the tube, which unblocks the firing rod.

Windblast is common in longwall coal mines, especially those whose roof strata are competent, and do not cave immediately behind the roof supports as the face advances. This results in the tendency for a large void to be created behind the roof supports in the goaf (or gob) which collapses when the overlying cantilevered strata can no longer support its own weight. When the collapse occurs, the air or gas occupying the void is displaced by rock, resulting in a pressure wave and windblast that propagates along the roadways (tunnels) of the mine. This may be followed by a "suck back" as the air pressure is equalised with the low pressure created higher up in the goaf.

The effect of the last ball ejecting with a velocity nearly equal to the first ball can be seen in sliding a coin on a table into a line of identical coins, as long as the striking coin and its twin targets are in a straight line. The effect can similarly be seen in billiard balls. The effect can also be seen when a sharp and strong pressure wave strikes a dense homogeneous material immersed in a less-dense medium. If the identical atoms, molecules, or larger-scale sub-volumes of the dense homogeneous material are at least partially elastically connected to each other by electrostatic forces, they can act as a sequence of colliding identical elastic balls.

Glass nozzles had to be made with drawn glass tubes, cut to size and polished to produce a flat nozzle orifice surface. Howtek introduced single nozzle Tefzel molded nozzles sliced with a razor and produced a full color thermoplastic material sheet Pixelmaster printer in 1986 with 32 single nozzles (8 for each primary color). The Tefzel nozzle material operating at 125C allowed only the voltage pulse energy to trigger an acoustical pressure wave in the fluid without coupling the high frequency vibrations from the piezo that cause spray and fluid vibration as the drops are ejected. Earlier inkjet designs with glass nozzles were also resonance sources and when packed with vibration dampening material could never eliminate spray.

Their usage was officially confirmed.The sensational statement of the representative of public prosecutor: "Tanks and flame throwers were used during the storm", Novaya Gazeta 7 April 2005 (Pravda Beslana translation/mirror) The Shmel is a type of thermobaric weapon, described by a source associated with the US military as "just about the most vicious weapon you can imagine – igniting the air, sucking the oxygen out of an enclosed area and creating a massive pressure wave crushing anything unfortunate enough to have lived through the conflagration." Pavel Felgenhauer has gone further and accused the government of also firing rockets from an Mi-24 attack helicopter,How The School Was Stormed, Novaya Gazeta, 7 October 2004. a claim that the authorities deny.

The main mechanism of detonation propagation is of a powerful pressure wave that compresses the unburnt gas ahead of the wave to a temperature above the autoignition temperature. In technical terms, the reaction zone (chemical combustion) is a self-driven shock wave where the reaction zone and the shock are coincident, and the chemical reaction is initiated by the compressive heating caused by the shock wave. The process is similar to ignition in a Diesel engine, but much more sudden and violent. Under certain conditions, mainly in terms of geometrical conditions (such as partial confinement and many obstacles in the flame path that cause turbulent flame eddy currents), a subsonic flame may accelerate to supersonic speed, transitioning from deflagration to detonation.

The amplitude of the pressure wave provides information about the local absorption and propagation of energy in the sample, while the time interval between the illumination pulse and arrival of the ultrasound wave at the detector provides information about the distance between the detector and photoecho source. Optoacoustic data collected over time and at multiple positions around the sample are processed using tomographic reconstruction to produce images of the distribution of photoabsorbers in the sample. Data collected after illumination at single wavelengths allow imaging of the distribution of photoabsorbers that share similar absorption characteristics at the given wavelength. Data collected after illumination with multiple wavelengths allow specific distinction of photoabsorbers with different optical absorption spectra, such as oxy- and deoxy-hemoglobin, myoglobin, melanin or exogenous photoabsorbers.

Before-and-after detonation of a K11A1 continuous rod warhead intended for the RAF Bloodhound Mk.2 When detonated, the high explosive imparts momentum to the rods, thrusting them outward in an expanding circle. The pressure wave from the explosive needs to act evenly on the rods over their length, so some sort of tamper is used to shape the shock wave similar to an explosive lens. The rods are sufficiently soft (ductile) to allow the expansion without breaking the rods or the welded joints, and the detonation velocity is limited to under 1,150 m/s, allowing the rods to bend at these locations instead. At some intermediate point the ring will have a zig-zag (alternating direction) appearance within a cylindrical envelope.

Putin Urged to Act on Summary Executions: Deaths of Sixteen More Civilians Confirmed, Total now Thirty-Eight, Human Rights Watch, February 10, 2000Civilian killings in Staropromyslovski district of Grozny, Human Rights Watch / United Nations High Commissioner for Refugees report, February 2000 The bombing of Katyr-Yurt occurred on 4–6 February 2000. The 1999–2000 siege and bombardments of Grozny caused thousands of civilians to perish. The Russian armed forces also used imprecise Fuel-Air Explosive bombs, also known as "vacuum bombs", which destroy shelters, buildings and bunkers, making it impossible to protect the civilians from their destructive nature in the populated areas. Their pressure wave kills through a subsequent rarefaction, a vacuum, which ruptures the lungs or causes people to suffocate.

The mine shell is a more explosive version of the common high-explosive and high-explosive fragmentation shells, relying on inflicting damage primarily through the blast rather than via the combination of penetration, blast and fragmentation achieved by normal ammunition. This is referred to in Swedish as tryckvågsverkan, meaning pressure wave damage. This effect is desirable when attacking materials such as concrete or aircraft skin that are relatively easy to penetrate and therefore do not need to be tackled with heavy, hard projectiles, but are tough enough to maintain their structure despite being pierced by shellfire. The larger explosions generated by mine shells are more efficient at inflicting damage on such targets than the greater kinetic impact but smaller detonations delivered by conventional rounds.

Additionally, current researchers have correlated helmet design to an amplification of waves that may cause bTBI. Moss et al. (2009) used model human heads outfitted with helmets approved for use in OEF and OIF and subjected them to blast waves at 194G for 2.1 milliseconds. These helmets, the Modular Integrated Communications Helmet (MICH) feature a mesh netting that offers comfort between the wearer’s head and the helmet’s Kevlar shell. While effective against ballistic trauma, Moss’s group reported that skull flexure is amplified by the air interface between the helmet and the skull. This space may amplify the effects of bTBI, and the group suggested that a foam connection between the helmet and the wearer’s head may diminish the effects of the peak pressure wave during an explosion.

The speed of the spike, and the immense pressure it caused on impact allowed it to create a small hole in armour plating and send a large pressure wave and large amounts of fragments into the interior of the target. It was this technology that was utilized in the No. 68 anti-tank grenade. PIAT and ammunition case at the Canadian War Museum Although the technology existed, it remained for British designers to develop a system that could deliver shaped charge ammunition in a larger size and with a greater range than that possessed by the No. 68. At the same time that Mohaupt was developing shaped charge ammunition, Lieutenant Colonel Stewart Blacker of the Royal Artillery was investigating the possibility of developing a lightweight platoon mortar.

Every fish has two Mauthner cells, located in the bottom part of the brainstem, one on the left side and one on the right. Each Mauthner cell has an axon that crosses over, innervating (stimulating) neurons at the same brain level and then travelling down through the spinal cord, making numerous connections as it goes. The synapses generated by a Mauthner cell are so powerful that a single action potential gives rise to a major behavioral response: within milliseconds the fish curves its body into a C-shape, then straightens, thereby propelling itself rapidly forward. Functionally this is a fast escape response, triggered most easily by a strong sound wave or pressure wave impinging on the lateral line organ of the fish.

The ensign was re-rigged on the tip of one of the foremast yardarms which, constrained by the rigging, was now hanging vertically from the remains of the foremast and was the highest point of the wreck. In the late afternoon of 21 November, movement of the remaining wreckage was noticed as another pressure wave hit. Within the space of a minute, the stern of the Endurance was lifted clear of the ice as the floes moved together and then, as the pressure passed and they moved apart, the entire wreck fell into the ocean. By daylight the following day, the ice surrounding the spot where the Endurance had sank had moved together again, obliterating any trace of the wreck.

Every fish has two Mauthner cells, located in the bottom part of the brainstem, one on the left side and one on the right. Each Mauthner cell has an axon that crosses over, innervating neurons at the same brain level and then travelling down through the spinal cord, making numerous connections as it goes. The synapses generated by a Mauthner cell are so powerful that a single action potential gives rise to a major behavioral response: within milliseconds the fish curves its body into a C-shape, then straightens, thereby propelling itself rapidly forward. Functionally, this is a fast escape response, triggered most easily by a strong sound wave or pressure wave impinging on the lateral line organ of the fish.

Inertial supercharging effect is the result of incoming fuel/air charge developing momentum greater than intake stroke would generate alone. It is achieved by the careful design of the shape of the piston head, the valves and cam profile/valve timing which creates a vacuum that pulls more exhaust gases (and some of the intake gasses) out of the engine. This is immediately followed by a reflected pressure wave timed to force the extra intake gasses back into the cylinder, thus achieving a greater mass of air/fuel mix in the combustion chamber than possible with conventional methods. Expansion chambers only work well at a narrow engine speed range which is why two stroke engines are referred to as having a "powerband".

The synapses generated by a Mauthner cell are so powerful that a single action potential gives rise to a major behavioral response: within milliseconds the fish curves its body into a C-shape, then straightens, thereby propelling itself rapidly forward. Functionally this is a fast escape response, triggered most easily by a strong sound wave or pressure wave impinging on the lateral line organ of the fish. Mauthner cells are not the only identified neurons in fish—there are about 20 more types, including pairs of "Mauthner cell analogs" in each spinal segmental nucleus. Although a Mauthner cell is capable of bringing about an escape response individually, in the context of ordinary behavior other types of cells usually contribute to shaping the amplitude and direction of the response.

In a set of tuned headers the pipe lengths are carefully calculated to enhance exhaust flow in a particular engine revolutions per minute range. A common method of increasing the power output of an engine is the use of upgraded headers. The increased power output is often due to a result of a larger cross-section area of the pipes (reducing the resistance on the exhaust gasses) and/or designing the pipe lengths so that the pressure wave assists in exhaust scavenging. For inline-four engines and V8 engines, exhaust manifolds are usually either a 4-2-1 design (where the four pipes merge into two, followed by a separate merge of these two pipes into one) or a 4-1 design (where the four pipes directly merge into one).

Also, in addition to the initial pressure wave, a jet effect caused by the expansion of compressed gases (compression-driven) or production of rapidly expanding gases (blast-driven) follows and may transfer momentum to a sample after the blast wave has passed. More recently, laboratory scale shock tubes driven by fuel-air mixtures have been developed that produce realistic blast waves and can be operated in more ordinary laboratory facilities. Because the molar volume of gas is much less, the jet effect is a fraction of that for compressed-gas driven shock tubes. To date, the smaller size and lower peak pressures generated by these shock tubes make them most useful for preliminary, nondestructive testing of materials, validation of measurement equipment such as high speed pressure transducers, and for biomedical research as well as military applications.

Comparison of 1D, 2D and 3D phononic crystal structures where the metamaterial exhibits a periodic variation of sound speed in 1, 2 and 3 dimensions (from left to right, respectively).Acoustic metamaterials or phononic crystals can be understood as the acoustic analog of photonic crystals: instead of electromagnetic waves (photons) propagating through a material with a periodically modified optical refractive index (resulting in a modified speed of light), the phononic crystal comprises pressure waves (phonons) propagating through a material with a periodically modified acoustic refractive index, resulting in a modified speed of sound. In addition to the parallel concepts of refractive index and crystal structure, electromagnetic waves and acoustic waves are both mathematically described by the wave equation. The simplest realization of an acoustic metamaterial would constitute the propagation of a pressure wave through a slab with a periodically modified refractive index in one dimension.

This is fast enough for the Hertzian solution to not require a substantial modification to adjust for the delay in force propagation through the balls. In less-rigid but still very elastic balls such as rubber, the propagation speed is slower, but the duration of collisions is longer, so the Hertzian solution still applies. The error introduced by the limited speed of the force propagation biases the Hertzian solution towards the simple solution because the collisions are not affected as much by the inertia of the balls that are further away. Identically-shaped balls help the pressure waves converge on the contact point of the last ball: at the initial strike point one pressure wave goes forward to the other balls while another goes backward to reflect off the opposite side of the first ball, and then it follows the first wave, being exactly 1 ball-diameter behind.

The word mine in the name mine-shell, although in English it's directly translated from the German word minengeschoß, does not refer to the modern use of the word, for example land mine and naval mine. Mine is an old (but still used) munition term from, among others, the weapons terminologies of Germany and Sweden. While the munition term "mine" in its original languages (German: Mine, Swedish: min) differs from their respective words for land mines (German: Landmine, (or just) Mine, Swedish: mina) the munition term originates from the original meaning of the word mine which originally meant something along the lines of explosive ordnance, unlike the modern meaning of the word which is more defined. The munition term itself (German: Minenwirkung, Swedish: minverkan), which roughly translates to "mine power" or "mine effect", specifically means an explosive device, mainly a projectile, that damages its intended target with the power of the pressure wave created from the explosion.

Auditory response to transmitted frequencies from approximately 200 MHz to at least 3 GHz has been reported. The cause is thought to be thermoelastic expansion of portions of auditory apparatus, and the generally accepted mechanism is rapid (but minuscule, in the range of 10−5 °C) heating of brain by each pulse, and the resulting pressure wave traveling through the skull to the cochlea. In 1975, an article by neuropsychologist Don Justesen discussing radiation effects on human perceptions referred to an experiment by Joseph C. Sharp and Mark Grove at the Walter Reed Army Institute of Research during which Sharp and Grove reportedly were able to recognize nine out of ten words transmitted by "voice modulated microwaves". Since the radiation levels approached the (then current) 10 mW/cm² limit of safe exposure, critics have observed that under such conditions brain damage from thermal effects of high power microwave radiation would occur, and there was "no conclusive evidence for MAE at lower energy densities".