Flow Angle and Shear Stress Measurements Using Heated Films and Wires

The heat transfer characteristics of yawed slender filaments have been generalized to include pairs of heated-film skin friction gages, as well as conventional hot wire probes, New sensor designs have been combined with a novel double-bridge electronic feedback system with accurate differential power capabilities for improved measurements in complex environments. Results of detailed calibration experiments illustrate the accuracy, simplicity, and utility of the probe designs and circuit techniques.