Nutating mixers are used in gentle three-dimensional (gyrating) agitation of chemical or biological scientific procedures by repetitively moving the vessels holding the liquids. Trivedi. Open Source 3-D Printed Nutating Mixer. Applied Sciences, 2017, 7(9), 942; doi:10.3390/app7090942 The nutating motion is widely employed in flowmeters and pumps. The displacement of volume for one revolution is first determined.
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Operation of the Dakeyne nutating disk engine A nutating disc engine (also sometimes called a disc engine) is an internal combustion engine comprising fundamentally of one moving part and a direct drive onto the crankshaft. Initially patented in 1993, it differs from earlier internal combustion engines in a number of ways and utilizes a circular rocking or wobbling nutating motion, drawing heavily from similar steam-powered engines developed in the 19th century, and similar to the motion of the non-rotating portion of a swash plate on a swash plate engine.
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In engineering, a nutating motion is similar to that seen in a swashplate mechanism. In general, a nutating plate is carried on a skewed bearing on the main shaft and does not itself rotate, whereas a swashplate is fixed to the shaft and rotates with it. The motion is similar to the motions of coin or a tire wobbling on the ground after being dropped with the flat side down. Precession is the physical term for this kind of motion.
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The nutating disc meter which uses the same geometry and concept as the Dakeynes' original engineNiagara Meters: Nutating Disc DrawingHersey Meters - 400 Series Positive Displacement Disc Water Meter is probably the most widely used flowmeter in the world, and it is claimed that more than half the water meters installed in domestic premises in the US and Europe are of this type. Used for 150 years, it is essentially a Dakeyne Disc Engine and was most probably developed by Farey and Donkin who mentioned a "fluid measurement meter" in their 1850 disc engine patent granted in 1850. By 1859 they were being manufactured by the Buffalo Meter Company of Buffalo, New York.
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Water meter in Belo Horizonte. Displacement meters are commonly referred to as Positive Displacement, or "PD" meters. Two common types are oscillating piston meters and nutating disk meters. Either method relies on the water to physically displace the moving measuring element in direct proportion to the amount of water that passes through the meter.
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There are two common approaches to flow measurement, displacement and velocity, each making use of a variety of technologies. Common displacement designs include oscillating piston and nutating disc meters. Velocity-based designs include single- and multi-jet meters and turbine meters. There are also non-mechanical designs, for example, electromagnetic and ultrasonic meters, and meters designed for special uses.
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The speed of the device in revolutions per unit time is measured. In the case of flowmeters, the product of the rotational speed and the displacement per revolution is then taken to find the flow rate. A nutating disc engine was patented in 1993 and a prototype was reported in 2006. The engine consisted of an internal disk wobbling on a Z-shaped shaft.
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The wobbly web effectively "folds" a coned disc wheel into pleats, making it narrower again, but retaining the axial stiffness. This pleated disc is also stiffer against nutating forces. In architecture, similarly, a 'serpentine wall', is strengthened against sideways forces by corrugation, allowing a thinner, lighter, cheaper structure. A wobbly web wheel is a disc wheel with additional shaping, rather than a spoked wheel with merged spokes.
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The launching aircraft will illuminate the target with its radar. In radars of the 1950s these were single target tracking devices using a nutating horn as part of the antenna. This caused the beam to be swept in a small cone. Signal processing would be applied to determine the direction of maximum illumination and so develop a signal to steer the antenna toward the target.
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This is the most commonly used measurement system for measuring water supply in houses. The fluid, most commonly water, enters in one side of the meter and strikes the nutating disk, which is eccentrically mounted. The disk must then "wobble" or nutate about the vertical axis, since the bottom and the top of the disk remain in contact with the mounting chamber. A partition separates the inlet and outlet chambers.
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A disk mounted on a sphere is “wobbled” about an axis by the fluid flow and each rotation represents a finite amount of fluid transferred. A nutating disc flow meter has a round disc mounted on a spindle in a cylindrical chamber. By tracking the movements of the spindle, the flow meter determines the number of times the chamber traps and empties fluid. This information is used to determine flow rate.
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The nutating disc engine was an unusual development, based on a design that dated back to the 1820s. In this engine the normal piston and cylinder was replaced by an oscillating disc. In 1849 Rennie employed George Daniell Bishopp as a foreman at their works, and he held an 1848 patent regarding this form of engine. Although the engines appear to have worked sufficiently well for several full scale trials, they had an inherent problem with their seals, and this appears to have been the main reason they were not a success.
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It is flexible for axial loads, perpendicular to the disc plane and also for nutating, wobble of the axle at an angle to the main axis. A coned disc also becomes stiff against axial loads, as the web is no longer purely perpendicular to the axis of the wheel. Unlike a flat disc, there is no direction where the whole of a coned disc would be perpendicular (and thus flexible) to it. A drawback of a simple cone is that the wheel now becomes wider, along the axis.
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"Please excuse my not mailing this," the letter concluded, "but I don't know your new address." Unable to focus on research problems, Feynman began tackling physics problems, not for utility, but for self-satisfaction. One of these involved analyzing the physics of a twirling, nutating disk as it is moving through the air, inspired by an incident in the cafeteria at Cornell when someone tossed a dinner plate in the air. He read the work of Sir William Rowan Hamilton on quaternions, and attempted unsuccessfully to use them to formulate a relativistic theory of electrons.
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Displacement of the alignment of the fixed plate is transferred to the rotating plate, where it becomes reciprocal motion of the rotor blade linkages. This type of pitch control, known as cyclic pitch, allows the helicopter rotor to provide selective lift in any direction. Nutating flowmeters and pumps have similar motions to the wobble of a swashplate, but do not necessarily transform the motion to a reciprocating motion at any time. Active Electronically Scanned Array (AESA) radars are flat plates that can scan up to sixty degrees in any direction from directly ahead of them.
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In its basic configuration the core of the engine is a nutating non-rotating disc, with the center of its hub mounted in the middle of a Z-shaped shaft. The two ends of the shaft rotate, while the disc "nutates", (performs a wobbling motion without rotating around its axis). The motion of the disc circumference prescribes a portion of a sphere. A portion of the area of the disc is used for intake and compression, a portion is used to seal against a center casing, and the remaining portion is used for expansion and exhaust.
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The compressed air is admitted to an external accumulator, and then into an external combustion chamber before it is admitted to the power side of the disc. The external combustion chamber enables the engine to use diesel fuel in small engine sizes, giving it unique capabilities for unmanned aerial vehicle propulsion and other applications. One significant benefit of the nutating engine is the overlap of the power strokes. Power is transmitted directly to the output shaft, (the crankshaft), completely eliminating the need for complicated linkages essential in a conventional piston engine (to convert the piston's linear motion to rotating output motion).
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In nearby Two Dales, Ladygrove Mill was built for spinning cotton by Abraham Flint, but converted to flax spinning in 1789 by Daniel Dakeyne of Knabb House. It was expanded by his sons, Edward and James, who built a series of three dams on the Sydnope Valley rising to 96 feet. To cope with the water pressure, they invented a revolutionary water-pressure powered "disc engine", which they patented in 1830 as the Dakeyne hydraulic disc engine."The Romping Lion" - The story of the Dakeyne Disc Engine by Phil Wigfull It was the progenitor of a type, now known as a "nutating disc engine" (which has been the subject of entrepreneurial interest in the 21st century).
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Alexander’s research career has focused on thermal or fluid sciences and applications on the design of power and propulsion systems, energy conversion systems, renewable energy and engineering systems and components. He also conducted research on unsteady thermo-fluid dynamics and unsteady transport phenomena within those areas, the performance of turbomachinery and airfoils, a novel method to predict gas turbine and piston engine emissions, development of a novel Nutating disc engine for unmanned aerial vehicles and on fluid-dynamic modeling of the cardiovascular system, and development of mechanical circulatory support devices. Alexander holds two patents on biomedical devices, he is a co-author of a textbook on turbomachinery design and has published more than 120 research papers in archival scientific journals.
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Despite the problems indicated above this type of pump can contain most of the necessary circuit controls integrally (the swash-plate angle control) to regulate flow and pressure, be very reliable and allow the rest of the hydraulic system to be very simple and inexpensive. Axial piston pumps are used to power the hydraulic systems of jet aircraft, being gear-driven off of the turbine engine's main shaft, The system used on the F-14 used a 9-piston pump that produced a standard system operating pressure of 3000 psi and a maximum flow of 84 gallons per minute. Automotive air conditioning compressors for cabin cooling are nowadays mostly based around the axial piston pump design (others are based on the scroll compressor or rotary vane pump ones instead) in order to contain their weight and space requirement in the vehicle's engine bay and reduce vibrations. They're available in fixed displacement and dynamically adjusted variable displacement variants, and, depending upon the compressor's design, the actual rotating swashplate either directly drives a set of pistons mated to its edges through a set of hemispherical metal shoes, or a nutating plate on which a set of pistons are mounted by means of rods.
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