This paper focuses on the simulation of ice accretion shape with roughness features during a Computational Fluid Dynamic (CFD) procedure. A new tentative approach called layer pavement model, or icing mosaic method, is described. In-flight ice accretion is a complex phenomenon, while rime icing is well known and can be adequately simulated, glaze icing however is harder to predict to a satisfactory standard. Rime ice shapes tend to be uniform in their surface roughness. Glaze ice shapes may be very irregular. Previous studies have proved that by using a non-uniform roughness distribution on an iced surface, it is possible to improve the accuracy of the simulation. In different areas on a real iced surface, the roughness should behave as different patterns or textures, according to geometric configuration and atmospheric conditions. The icing mechanism and their patterns or textures could be ultimately classified as here the layer pavement method presented. Alike the typography technology, by layer pavement method each surface grid discrete in CFD would be given an appropriate 'type' during each ice build-up iteration step. When the height of local roughness somewhat exceeded the local grid size in certain proportion, which means new facets occur and the ice growth will has new foundations and directions. Hereby rapid-growing ice branches and feathers could be introduced into the CFD process better, so the irregular ice shape such as so-called 'lobster tails' or 'scallops' observed in wind tunnels and inflight will be likely to established in CFD simulations.
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