Robust, High Sensitivity, Dynamic Wall Shear Sensors for Flow Diagnostics

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

Abstract 0510238 PI: Pavlos Vlachos, Virginia Tech Wall shear stress measurements and the contribution of shear stresses to the viscous drag of air and water vehicles are critically important for numerous applications. The sensitivity and accuracy needed to quantify the wall shear stresses in complex unsteady flows is not attainable with the existing state-of-the-art measurement technologies. This research effort provides a paradigm shift in direct sensing of wall shear stresses by employing ionomeric electroactive polymer transducers. Preliminary results demonstrate that this active material exhibits exceptional sensitivity to flow-induced shear stress with high accuracy and high frequency response. In addition, it allows fabrication of miniature flush mountable sensors that eliminate moving parts increasing robustness, ease of implementation and reducing cost. Ionic polymer transducers have never been used for wall shear sensing thus the electromechanical coupling mechanism that provides shear transduction is not understood. This program will determine the fundamental sensing properties of ionic polymer transducers under wall shear will improve sensor fabrication and packaging and will develop a methodology for high frequency dynamic calibration. A variety of possible applications ranging from biofluids to classical aerodynamics will be explored. This is a project supported under the Sensor Initiative NSF 05-526.