Adjoint equations-based grid adaptation and error correction

Based on the discrete adjoint optimizing theory and three-dimensional unstructured grid,agrid adaptation technology and an error correction method for objective function are built.A method to predict and correct the error of objective function using adjoint equations is presented.Then,an interpolation technology which suits for centre-based finite volume method is proposed,some methods to divide tetrahedral grids,project surface grids and optimize spatial grids are discussed,and a complete grid adaptation system which suits for finite volume method is built.Finally,the grid adaptation method is applied to the simulation of inviscid flows around NACA0012 airfoil and ONERA-M6 wing,and the error of objective function,such as the coefficient of drag and lift,is corrected.Numerical results show that the sensitive grids for objective function are detected and refined by this grid adaptation method,and the accuracy of objective function is obviously improved after grid adaptation and error correction.