Accurate aerodynamic sensitivity analysis using adjoint equations

Abstract

An accurate aerodynamic sensitivity analysis method for the adjoint approach is described, The present method uses the continuous adjoint approach to avoid excessive memory requirement, and the diagonalized alternating direction implicit (DADI) relaxation with multigrid acceleration is used for the fast convergence. A derivation of the continuous adjoint operator is described for the second-order total variation diminishing (TVD) scheme and a new antidiffusive flux for the adjoint equations is proposed to enhance the accuracy of sensitivity. The accuracy of the present method is demonstrated by solving sensitivity problems for two-dimensional airfoils. Comparisons with finite difference results are also presented.