International Journal of Heat and Mass Transfer, Vol.138, 713-718, 2019
A laser interferometric measurement on the melt film thickness during close-contact melting on an isothermally-heated horizontal plate
In this work, the laser interferometric method was employed for the first time to measure directly the melt film thickness during close-contact melting of a phase change material on an isothermally-heated horizontal plate. It was shown that the melt film thickness grows rapidly after the incipience of melting, then the growth rate slows down when melting gradually approaches the quasi-steady state. The measured results were in good agreement with the predicted trends based on a mathematical model. It was confirmed by the direct measurement results that the magnitude of quasi-steady state melt film thickness is around 200 mu m for the various cases studied. However, there was always a systematic underestimation of the measured thickness, as compared to the theoretical predictions, which was likely attributed to the departure of the mathematical model from the real case and the oversimplified assumptions made. (C) 2019 Elsevier Ltd. All rights reserved.