Grid density effect for numerical simulation of civil aircraft in post stall

Abstract

Stall will deteriorate flight safety and cause serious accidents for civil aircraft. RANS-LES hybrid approaches have become a compromise choice due to insufficient ability of RANS for large flow separation. In present work, Zonal Detached-eddy-simulation coupled with high-order spatial scheme were employed to investigated grid density effect in the numerical simulations. The calculations show that the grid density would affect the numerical simulation of the small-scale flow structure in the wake of region of the main wing, and further affect the disturbance of main wing to the horizontal tail. It is necessary to properly densify the grid downstream of the main wing in order to accurately predict the aircraft stall.