Design Optimization of Coanda Effect Based UAV using CFD Simulations

Abstract

Recently, Unmanned Aerial Vehicles (UAVs) have gained immense importance in many fields including agriculture, robotics, surveillance, mapping, search and rescue due to their ability to cover long distances quickly and hover above the surface. This research presents design optimization of a relatively new type of UAV which utilizes Coanda effect for lift augmentation. Computational fluid dynamics analysis is carried out to understand lift mechanism due to Coanda Effect for two common configurations as baseline models to gain insight into the lift generation. Propeller based configuration in which propeller is above the Coanda surface is found to be unfavorable for lift augmentation while centrifugal fan configuration is found to be viable. Analysis highlighted two important factors which necessitates design changes to improve performance. Variations in curved Coanda surface and lower part is carried out which improved the net lift generated. Finally the improved shape is optimized using adjoint solver. This novel and optimized model is called RISE Coanda which lowers the pressure drag and increase the net lift by approximately 50% as compared to baseline models.