Accurate aerodynamic sensitivity analysis using adjoint equations

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