Innovators at NASA Glenn Research Center (GRC) have patented a rocket motor joint and seal structure that provides enhanced thermal protection for elastomeric O-ring seals, and thus improved joint integrity. Under rocket motor firing conditions, if unprotected, O-ring seals can be damaged by high temperature exposure. When properly located in the joint, a braided rope-type thermal barrier comprised of carbon fibers provides superior protection to O-rings and protects motor casing sections from erosion and damage. Carbon fibers used to form the braided rope seal structure enable it to withstand 2200 degrees Fahrenheit temperatures over a long period with little or no damage to the barrier structure. Not only does the barrier endure high temperatures, it also remains flexible after high-temperature exposure. This flexibility improves its ability to retain its location in the joint. This in turn facilitates easy assembly, shipping, and storing, and reduces the chances of damage to or misalignment of the thermal barrier.

Innovators at NASA Glenn Research Center (GRC) have patented a high-temperature sealing system for structures that move relative to one another. This sealing system is capable of preventing parasitic gas flow between structures and accommodating both in-plane and out-of-plane structural movements of several inches. Movable, segmented sealing elements are able to conform to structure contours to create a fluid-tight seal. This seal is durable enough to block the infiltration of high-temperature gases, and flexible enough to accommodate large space displacements between structures. The system’s ability to prevent high-temperature gas flow and maintain structural integrity provides critical support in dealing with aerodynamic and thermal loads.

Innovators at NASA Glenn Research Center (GRC) have patented a non-contacting finger seal that is adapted to be interposed between relatively high- and low-pressure cavities to provide sealing along a rotating member. This technology helps minimize previous durability problems experienced with finger seals because this seal is capable of extended use in high-speed and high-temperature environments, such as those involving gas turbine engines. By lowering frictional heat generation, wearing of the seal and shaft is lessened, thus providing a longer life capacity.

Researchers at NASA Glenn Research Center (GRC) have patented an acoustic seal that exploits acoustic wave principles to generate a pressure barrier that prevents fluid leakage from a high-pressure area. Traditional sealing devices rely on a contacting relationship between surfaces and sealing elements to prevent fluid leakage, but in the case of moving elements, this contact produces friction that causes wearing and eventual failure of the sealing system. Friction also consumes energy and produces harmful debris. The patented seal employs acoustic technology to generate pressure waves that control, mitigate, or prevent fluid leakage. The result is a very low-leakage, non-contact seal, eliminating problems associated with friction. A coupled oscillating acoustic driver and resonator cavity, employing resonant macrosonic synthesis, create a pressure multiplying effect (4–10x or more) that enables optimal sealing.

Researchers at NASA Glenn Research Center (GRC) have patented a software-implemented system for dynamic stabilization control of a magnetically supported rotor to attain higher rotational speeds than possible with conventional bearings. The system optimizes performance through the introduction of correcting counter-perturbations in the magnetic field and makes off-axis operation possible. The software may be executed on a general- or specific-purpose computer and includes routines for implementing the desired operation.

Researchers at NASA Glenn Research Center (GRC) have patented a bearingless switched reluctance motor that utilizes a plurality of poles in the rotor and stator to achieve both rotation and levitation. Conventional switched-reluctance motors suffer from vibration caused by large magnetic attraction forces on the rotor. In addition, traditional motor bearings are subject to wear and require lubrication. By using magnetic bearings in place of traditional mechanical bearings as well as an improved stator design, this innovation improves the performance of switched reluctance motors, resulting in a higher load carrying capacity and enhanced vibration suppression.

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Researchers at NASA Glenn Research Center (GRC) have patented a new large-diameter, permanent-magnet electron cyclotron resonance (ECR) plasma source. Originally developed for incorporation into ion thrusters for long-duration space missions, the innovation features an electrodeless design to provide longer lifetimes than conventional systems with electrodes such as hollow cathode electron sources. The innovation can also be applied to various terrestrial plasma processes including semiconductor wafer processing such as etching. For industrial processes, the absence of electrodes results in greater reproducibility and alleviates problems with electrode erosion and the corresponding contamination. The novel design of the permanent magnet rings produces a uniform plasma over a large area.

Researchers at NASA Glenn Research Center (GRC) have patented a slotted antenna waveguide plasma source that produces a distributed, uniform plasma with a high density that is capable of yielding high etch rates or material deposition rates. The slotted antenna is part of an electron cyclotron resonance (ECR) plasma system that incorporates only permanent magnets, as opposed to the less efficient electromagnets used in current commercial systems.

In addition, the antenna is windowless and electrodeless, which eliminates cathode erosion and contamination issues and thus provides a longer operation lifetime and improved processing. The slotted antenna plasma source electrodelessly generates uniform discharge plasma at reduced input powers and gas flows. Another advantage of the slotted antenna systems over conventional technology is the use of a slotted waveguide and rectangular discharge that permits direct scalability to larger areas and higher power generators.
 

Researchers at NASA Glenn Research Center (GRC) have patented a software-implemented system for testing the movement of a magnetically levitated rotor. Certain disturbances imposed on a rotor’s movement can limit its rotational speed and reduce the operating life of its components. This system uses software controls to introduce a wide variety of disturbances to the rotor to investigate the performance of the rotor under different conditions. In addition, the rotor assembly is suspended by magnetic bearings, allowing it to attain higher speeds without the stress of rotation-dependent vibrations and fatigue that limit the operational speed and life of traditional ball bearings. The system can be used as a static or dynamic test bed of disturbances at higher speeds for rotating components used in turbomachinery.