중첩 격자 기법을 이용한 지면 효과를 받는 RAE 101 익형의 공력 해석

Abstract

It takes a lot of time and effort to generate grids for numerical analysis in ground effect because relative attitude and height of the airfoil must be maintained to the ground as well as inflow. Low Mach number preconditioned turbulent flow solver using the overlap grid has been developed and applied to the ground effect simulation. It has been validated that the present method using the multi-block grid give us highly accurate solutions by comparing to the experimental data of the RAE 101 airfoil in unbounded condition. Present numerical method has been extended to simulate the ground effect problems by using the overlapped grid system to avoid tedious work in generating multi-block grid system. An extended method using the overlapped grid has been verified and validated by comparing with the results of multi-block method and experimental data also. Consequently, the overlapped grid method is not only show sufficiently accurate solutions but very efficient to simulate ground effect problems. It is shown that pressure center and aerodynamic center move to backward direction by the ground effect as an airfoil approaches the ground.