Innovators at NASA’s Dryden Flight Research Center have developed, flight-tested, and patented a force-based flow-angle probe (FLAP) for measuring local flow direction. Local flow angle measurements are critical in many fluid-dynamic applications, such as aerodynamic flight testing of new aircraft and flight systems, engine flowpaths, extreme environments, pipelines, and nautical systems. The Dryden-developed probe is a small aerodynamic, low aspect ratio fin with no moving parts. The probe computes flow angle from forces measured by strain gauges mounted to the upper and lower surfaces of the probe. A correlation is then used to convert force-measurement data to the local flow angle. Conventional flow angle probes use a pivoting “weather vane” mechanism to determine local flow direction, but these designs are relatively bulky and thus have limited application for evaluating fluid flow in small regions, confined spaces, or harsh environments. Such probes are ill-suited for transonic and supersonic regimes flown by many military and research aircraft because they are affected by local shock waves. In addition, conventional probes cannot be utilized in specialized environments such as engine flowpaths due to their size, movement, response time, and intolerance to extreme temperatures. To further reduce the size of the Dryden innovation, conventional strain gauges can be replaced with fiber optic wires, which are even more sensitive to strain. A probe with strain-detecting fiber optic wires can be used to perform tests on individual streamlines in an airflow, rather than simply to monitor gross airflow behavior.
This technology has potential to be used by commercial and military aircraft manufacturers, commercial nautical systems, commercial pipelines, as well as researchers measuring local flow angle in aerodynamic and hydrodynamic environments:
Dryden has one patent issued (U.S. Patent No: 6,526,821→ ) for this technology.
› Read “Probe Without Moving Parts Measures Flow Angle”→ published in NASA Tech Briefs
This technology is part of NASA’s technology transfer program. The program seeks to stimulate development of commercial uses of NASA-developed technologies. NASA is flexible in its agreements, and opportunities exist for licensing and joint development. Dryden is interested in a partnership to commercialize this technology.
If you would like more information about this technology or about NASA’s technology transfer program, please contact:Julie Holland