A study of the effective thermal conductivity of frost formed on parallel plate channels

This paper presents an experimental study of the thermal conductivity of frost accumulated on parallel plate channels considering different operating conditions. The experimental work was carried out by means of a purpose-built closed-loop wind-tunnel facility, which provides a strict control of the psychrometric conditions at the entrance of the test section as well as the plate surface temperature. A dataset comprising of 57 experimental data points was gathered in order to come out with a semi-empirical correlation for the thermal conductivity of frost as a function of the frost porosity and the plate surface temperature. The correlation, which is based on the weighted geometric mean of the thermal resistances of moist air and ice crystals, is able to predict ∼90% of the experimental data points within the ±15% thresholds.