Flexible Wing of HALE UAV using Two-way Fluid Structure Interaction Method

Abstract

Numerical simulation of flexible High Altitude Long Endurance Unmanned Aerial Vehicle (HALE UAV) wing using two-way fluid structure interaction (FSI) method is presented. The HALE wing is designed with high aspect ratio. This configuration intended to reduce the vehicle induced drag and reduces the lift-loss at wingtip which caused by wingtip vortex. But the structure of the wing itself becomes more elastic that be able to give large deformation when the aerodynamic loads applied. This deformation causes the change of aerodynamic loads distribution on the wing. Then this provides a new deformation to the wing structure and vice versa. This interaction in a couple process called as fluid structure interaction (FSI) will be simulated using ANSYS 15.0 software for HALE wing. The unsteadiness and viscous flows at low speed are evaluated using the solution of time-dependent Reynolds Averaged Navier-Stokes (RANS) with SST k-ω turbulent model. In addition, multi-block structured grids are generated to provide more accurate viscous result and to anticipate negative volume of the mesh which may occur due to the wing deformation during simulation. Five different simulations with variation of material characteristics including Young's modulus and Poisson's ratio are carried out. The results include global aerodynamic characteristics at various material characteristics.