Anti-icing characteristics of hierarchical micro-dimple textured surface generated by 3D resonant vibration assisted machining

Abstract

Anti-icing techniques are essential for safe functioning in applications such as aircraft and power transmission lines. In the present study, a long lasting and minimal maintenance required hierarchical micro-dimple surface textures were produced on a cylindrical specimen using a dual frequency surface texturing method. The water contact angle and time delay in freezing on five diverse type of micro-dimples with three different surface texture densities and non-textured surfaces were examined and compared experimentally. The textured surfaces showed an approximately 28 % increase in delayed time compared to non-textured surfaces. A size effect on the performance of micro-dimples was observed. Smaller size micro-dimples have better delayed time for higher texture density surfaces. The delayed time increases with the increase in micro-dimple size for optimum and low texture density surfaces. Introducing of hierarchical structures increased the delayed time by 8 % compared to single scale micro-dimple surface textures. The idea of introducing hierarchical micro-dimples as an anti-icing technique will directly result in improving the delayed time, which in turn reduces the load on the secondary system for ice removing and improves its working efficiency.