New technique for mapping heat-transfer coefficient contours

Abstract

A new technique for mapping heat-transfer coefficient contours quickly and easily is presented. The technique utilizes cholesteric liquid crystals to infer surface temperatures. The tests conducted to ’’qualify’’ the technique for quantitative determination of heat-transfer coefficient are outlined. The experimental results obtained from this technique in simple flow situations are compared to measurements taken with conventional techniques. The frequency response of the instrument to fluctuations in heat-transfer coefficient is shown to be at least 1.3 Hz.