Experimental and numerical investigations of frost formation on wavy plates

Abstract

In this work, frost formation on wavy plates with −5 to 2 °C air temperatures, 85% air relative humidity, 0.31–0.92 m/s air velocities and −20 to −5 °C cooling surface temperatures was experimentally and numerically investigated. In the experiments, the frost layer growth process was recorded with frost thickness and weight measured. The experimental results show that the frost thickness increases with time and the frost layer grows faster with higher phase change driving force and higher water vapor mass flux. In the simulations, a frosting model was implemented as the source term in the Euler multi-phase flow method to simulate frosting process. The simulation results of frost layer growth show that densest frost appears at the leading edge of the plate. The frost density on the peaks of the plate is larger than that on the bottom of the valley. The simulations show that the air velocity increases with the frost layer growing. The simulated frost profile, frost weight and frost thickness agree well with the experimental results, which means the frosting model can be used to predict frost formation on wavy plates.