The Icing of an Unheated, Nonrotating Cylinder. Part II. Icing Wind Tunnel Experiments

Abstract

An experimental investigation of icing on non-rotating cylinders, under both wet and dry conditions was undertaken. Airspeeds of 30, 61 and 122 m s?1 appropriate to aircraft icing, liquid water contents of 0.4, 0.8 and 1.2 g m?3 and temperatures of ? 15, ? 8 and ? 5°C, were explored. Dry accretions were lenticular or ?spearhead? shapes, while wet accretions tended to develop ?horns? and stagnation line depressions as the result of the runback of unfrozen water away from the stagnation line and its subsequent freezing further around the perimeter of the cylinder. Comparisons were made between the experimental accretion shapes and those predicted by the model described in Part I. The model performed best under dry growth conditions. Under wet conditions, the model behavior, while qualitatively correct, was unable to exactly duplicate the details of the accretion profiles. Nevertheless, under both dry and wet conditions, the model predictions of the accretion cross-sectional areas, were quite accurate.