Near-Wall Turbulence and Skin Friction Measurements Using Ionic Polymer Sensors

This Phase II effort seeks to improve on ionic polymer-based wall shear sensors that were demonstrated during the Phase I. These sensors have many advantages over conventional technologies, including low cost, flexible packaging, high accuracy, large bandwidth, and low profile. The sensors also contain no moving parts and are inherently robust and able to operate in particulate flows. The Phase II will build on the results of the Phase I through improvements to the performance of the sensors and the methods used to characterize their performance. Through advancements to the fabrication process, the signal-to-noise ratio, sensitivity, and long-term stability will be improved. Also, upgrades to the test methods will allow the sensors to be characterized over a wider range of shear, Reynolds number, and frequency. This testing will include laminar tests with both constant and fluctuating shear as well as testing in turbulent boundary layers. Benchmarking and validation of the sensors will be performed against known analytical solutions for shear as well as other shear measurement technologies. The Phase II option will deliver a turnkey sensor interface system and see the sensors tested in additional facilities to more fully characterize the sensors’ performance over a wide range of flow conditions.