Non-contact frost thickness measurement by using a micro-camera and image processing technology

Frost thickness is a key parameter to examine the effect of frosting or defrosting in refrigeration field, but frost thickness is not easy to measure through traditional methods, for frost is soft and easily to be damaged by heat or pressure. Aim at the problem of frost thickness measurement, a measurement method based on a microscopic image system and image processing technology is brought forward, and the concept of bilateral frost thickness is proposed and explained. Experimental tests on the thickness of frost growing on the double sides of an aluminum sheet were carried out to clearly observe and record the dynamic growing process of tiny frost crystals. Experimental results show that the given measurement method does not undermine the patterns of frost during the whole frosting process, and it could observe frosting process easily, as well as measure the frost thickness with high accuracy. The given method is effective and it could be used to measure the growth of frost crystals and frost layer thickness on a cold surface, such as an aluminum sheet and a finned-tube evaporator.