A Novel Frost Detection: Applying Image Recognition with Wide-Angle Lens

Frost formation is unavoidable in refrigeration and air conditioning systems, which causes significant degradation of the thermal performance of evaporators and reduces the energy efficiency. Hence, accurate defrost control is necessary to ensure heat transfer capacity and operating efficiency. To improve the accuracy of defrosting timing of evaporators, the study investigated the feasibility of a novel frost accumulation detection, which was image recognition with a wide-angle lens. In the experiment, power consumption, cabinet temperature and frost accumulation were observed. The results reveal the minimum power consumption occurred at a certain defrost cycle. The study defined the frosting proportion to quantify the frost accumulation. The power consumption first decreased and then increased with frost proportion. Minimum average power consumption occurred at frosting proportion of 30%. The frosting proportion was positively correlated with power consumption with a coefficient of determination R-2 0.73, showing a good correlation.