A method of measuring frost thickness on a surface is presented. A low-power laser and sensitive light meter are used such that a precision of 0.025 mm is obtained for calibration measurements. Actual measurement of frost thickness shows some scatter (r.m.s. deviation is 4.3%) in repeated measurements. This scatter in frost thickness measurements is thought to be due primarily to slight variations in environmental conditions, initial starting conditions for each test, and random variations in frost crystal nucleation points. This method is used in an experimental study to investigate the influence of frost accumulation on the heat transfer rates across a frosted surface.

KEYWORDS: measuring, frost, thickness, lasers, light meters, surfaces, testing, heat flow.