Time-of-Flight Surface Acoustic Wave Sensor

To address the Navy’s need for high-accuracy, skin friction measurement of a fluid in underwater applications, Physical Optics Corporation (POC) proposes to develop a new Time-of-Flight Surface Acoustic Wave (TOFSAW) sensor. This proposed device is based on a new design for surface acoustic wave coupling to fluids for velocity measurement in 3D around the detection point. The innovation in the TOFSAW sensor design will enable the device to measure the velocity profile to give a measurement of the fluid frictional forces at high velocity and high Reynolds numbers (up to 20 million). As a result, this device offers better than 0.1% accuracy, self-calibration, digital-signal output, and small size, which directly address the Navy requirements. In Phase I, POC will demonstrate the feasibility of TOFSAW by developing a proof-of concept device to measure Reynolds numbers up to 1 million. In Phase II, POC plans to further mature the technology, testing it in fluid flows of Reynolds numbers of 10 million at the end of development.