Development of interferometric temperature measurement procedures for microfluid flow

In order to understand heat transfer processes at the microscale, detailed temperature measurements are required. This article begins with a review of the current state-of-the art in fluid temperature measurement at the microscale. At present, fluid temperature profiles are not measured, with verification of predicted heat transfer performance being based on global measurements. The article describes a potential full-field technique based on micro- interferometry. The accuracy of extracting temperature data from small phase difference intensity maps is discussed, with particular reference to the high levels of signal to noise as would be found in a microscale flow. Benchmark optical experiments quantifying the effect of noise on phase evaluation are described and the article concludes with an outline of the achievable resolution for a given channel length and fluid.