Acoustic Shear Stress Sensor for Flight Research

Through numerical simulations and wind tunnel testing, Nielsen Engineering & Research (NEAR) has demonstrated that their acoustic sensing technology can be used to quantify the magnitude and direction of the local shear stress vector. Because the instrument can 1) measure shear stress values up to 100 Pa, 2) account for atmospheric variations in local fluid properties, and 3) accommodate relatively large streamwise pressure gradients, it is well suited for use in flight test research and commercial aircraft applications. During the previous Phase I program, NEAR identified some deficiencies in the current sensor housing design. Thus, the proposed Phase II effort will focus on developing a robust housing which can withstand the vibration, temperature, pressure, and moisture levels found in flight. Sensor housing designs will be developed and refined through a series of wind tunnel tests using tunnels capable of simulating the flight environment. The final sensor design will be demonstrated through flight testing on NASA Dryden?s F-15B. In addition to the sensor redesign effort, NEAR will develop a flight-qualified electronics package for use in the flight test program.