Time-Sequence Observations of the Formation of Ice Accretions on Swept Wings

Abstract

This work presents the results of two complementary experiments, one conducted in the Icing Research Tunnel (IRT) at NASA Glenn Research Center and the other in the Goodrich Icing Wind Tunnel (IWT). The experiments were designed to study in real time the process by which ice accretions are formed on swept wings. In the IRT experiment a time sequence imaging technique (TSIT) was used to obtain real time data during the ice accretion formation. The time sequence photographic data was used to study the process frame by frame and to create movies of how the process developed in real time. A nonactivated heater located on the leading edge was used to study its effect on the formation of the ice shape. In the IWT experiment an improved TSIT was tested and additional data was taken at a baseline condition to clarify and complement the data from the IRT. The smaller IWT allowed greater optical access than the IRT providing increased field of view and an alternate grazing angle view. The data from the two experiments led to a more detailed conceptual model of how ice accretions develop.