Mechanical & Fluid Systems

Heavy Duty Shaft Coupling Strategies

Heavy-duty shaft couplings have traditionally had a couple of defining design characteristics. For one, these couplings usually rely on keyed shaft connections. For another, they tend to be overengineered with regard to stiffness. Keyed connections and excessively rigid coupling designs do have some under-recognized limitations— especially in large industrial, material handling, construction and mining machines.

Posted in: White Papers

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Coming Soon - Friction Reduction: Finding New Gains in Powertrain Efficiency

In conjunction with SAE International Facing the super-stringent U.S. and European CO2 emission requirements for 2020 and beyond, powertrain engineers need to squeeze every last tenth of a mile-per-gallon of efficiency out of new engines, transmissions, and drivelines. Reducing internal friction on rotating and reciprocating components, as well as across systems, is now a major design and engineering priority. New technology solutions in the critical areas of powertrain systems design, bearings, and seals are appearing as a result. This webcast’s panel of experts will examine these issues and offer solutions. Webcast attendees will be invited to interact with the experts during the Q&A portion of the 60-minute webcast.

Posted in: Upcoming Webinars

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Diminutive Assembly for Nanosatellite deploYables (DANY) Miniature Release Mechanism

New deployment mechanism offers improved reliability with minimum space and weight penalty. Goddard Space Flight Center, Greenbelt, Maryland CubeSat appendices such as solar panels and antennas often need to be constrained by a release mechanism during launch. These appendices are then deployed once the desired orbit is reached. The usual constraint method used is a combination of an unpredictable/ unreliable fishing line and burning wire. If a proper release mechanism is used, it utilizes a considerable amount of CubeSat internal space, making the internal packaging of the satellite more difficult. These two methods have adverse effects on CubeSat performance.

Posted in: Briefs, TSP

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Quantitative Real-Time Flow Visualization Technique

This technique enables real-time monitoring of pressure fields and flow measurement. John H. Glenn Research Center, Cleveland, Ohio There is a need for experimental techniques that have low cost and rapid turnaround. It is also necessary to obtain quantitative information from such a method. Previous methods are either lacking in quantitative information such as dye or smoke injection, or require considerable set-up and cost such as PIV (particle image velocimetry). A method was developed for visualizing the pressure contours for a turbine cascade in real time to enable rapid evaluation of new concepts. A method for quantitative 3D flow visualization also was developed.

Posted in: Briefs, TSP

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Thin-Film Evaporative Cooling for Side-Pumped Lasers

This technology has applications in advanced lidar systems for weather satellites; in welding, cutting, and marking; and in test and measurement. Langley Research Center, Hampton, Virginia A highly efficient way to cool solid-state crystal lasers was developed. This thin-film evaporative cooling technique offers higher optical efficiencies and monochromatic quality than traditional conductive cooling techniques. Developed for use in side-pumped 2.0- micron laser systems used in light detection and ranging (lidar) instruments, the thin-film cooling design concept also has broad utility for diode-pumped solid-state laser (DPSSL) systems, especially those with high heat flux or challenging packaging requirements.

Posted in: Briefs, TSP

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MEMS Micro-Translation Stage with Large Linear Travel Capability

Marshall Space Flight Center, Alabama A MEMS (microelectromechanical systems) micro-translation stage (MTS) with large linear travel capability was developed that uses capacitive electrostatic forces created by stators arranged linearly on both sides of a channel, and matching rotors on a moveable shuttle for precise movement of the shuttle. The device, which is essentially a linear motor built from silicon base with microfabrication techniques, will be able to rapidly translate across large distances using only three-phase power. The moveable shuttle can be as small as 100 mm and can house a variety of elements including lenses and mirrors. The shuttle can be tailored to travel distances as small as 10 mm and as large as 300 mm, with as little as 10 mm between adjacent shuttle stops.

Posted in: Briefs

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Planar and Non-Planar Multi-Bifurcating Stacked Radial Diffusing Valve Cages

This technology is applicable in systems and devices where high-pressure-differential valves are used. NASA’s Jet Propulsion Laboratory, Pasadena, California A valve cage consists of a stackable planar structure design with paths that are azimuthally cut out and connected radially. The pattern causes the flow to move azimuthally and impinge on each other when moving to the next path, thereby reducing the fluid momentum and energy that reduces the erosion capability. The maze-like structure is easy to machine with standard machining techniques.

Posted in: Briefs, TSP

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