The classification results from the automated system are comparable with that achieved using the manual approach. Index Terms—Aircraft Icing, Droplet Splash, …

The build up of water ice on aircraft flight surfaces poses a significant safety risk. As a result, much effort has gone into studying this problem in order to understand how individual droplets contribute to the accretion process. One approach has been to capture the moment of impact of a supercooled droplet onto a surface placed in an icing tunnel. However, this produces a large number of images that must be analysed manually. This paper describes the development of an automated analysis system, employing image processing techniques, that is capable of classifying the impact images without operator input. Using a carefully chosen feature vector and K-means clustering algorithm, the classification results from the automated system are comparable with that achieved using the manual approach.

Index Terms—Aircraft Icing, Extraction, Surface Classification Droplet Splash, Feature

INTRODUCTION

The topic of in-flight icing has been an important issue for many years. When aircraft fly through clouds or precipitation, icing will occur at temperatures below freezing. Given the importance of aviation flight safety, more research is required into in-flight icing. The two main fields being developed include large super-cooled water droplet impact for ice shapes prediction and understanding the ice accretion process for ice protection system. At Cranfield University, investigations are being carried out into the effects of super-cooled droplet impact splashes onto a simulated airfoil surface. The water droplets have similarity in size and speed in the ambient conditions relevant for super-cooled large droplet (SLD) icing. The term “SLD icing conditions” refers to the situation in which the cloud volume median diameter (VMD) is greater than 50µm and the water is cooled below zero Celsius degree but without freezing.[1]-[2], The material from which the airfoil surface is constructed plays an important role during ice formation process, as it may influence the extent to which water films build up. To monitor this process, image sequences are captured …

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