SOME MEASUREMENT TECHNIQUES IN HEAT TRANSFER.

Measurement techniques recently used to study heat transfer in free and forced convection systems are described. The techniques include application of mass transfer analogues and optical measurements, primarily interferometry. In the mass transfer systems, jets of foreign gas are used to simulate heat transfer during jet mixing, while sublimation of a surface gives a mass transfer analogue in which local transport coefficients can be measured quite accurately. Experiments with electrochemical systems using the transport of ions in aqueous solutions have significant advantages over more standard heat transfer experiments, including better control of boundary conditions.