A surface mesh movement algorithm,combining surface mesh mapping with Delaunay graph mapping,is proposed for surface mesh movement involving complex intersections,like wing/pylon intersections.First,surface mesh mapping is adopted for the movement of intersecting lines along the spanwise direction and the wing surface mesh,and then Delaunay graph mapping is utilized for the deformation of the pylon surface mesh,guaranteeing consistent and smooth surface meshes.Furthermore,the corresponding surface sensitivity procedure is implemented for accurate and efficient calculation of the surface sensitivities.The proposed surface mesh movement algorithm and the surface sensitivity procedure are integrated into a discrete adjoint-based optimization framework to optimize the nacelle position on the DLR-F6 wing-body-nacelle-pylon configuration for drag minimization.The results demonstrate that the strong shock on the initial pylon surface is nearly eliminated and the optimal nacelle position can be obtained within less than ten iterations. A surface mesh movement algorithm, combining surface mesh mapping with Delaunay graph mapping, is proposed for surface mesh movement involving complex intersections, like wing / pylon intersections. First, surface mesh mapping is adopted for the movement intersecting lines along the spanwise direction and the wing surface mesh, and then Delaunay graph mapping is utilized for the deformation of the pylon surface mesh, guaranteeing consistent and smooth surface meshes. Fuerthermore, the corresponding surface sensitivity procedure is implemented for accurate and efficient calculation of the surface sensitivities. movement algorithm and the surface sensitivity procedure are integrated into a discrete adjoint-based optimization framework to optimize the nacelle position on the DLR-F6 wing-body-nacelle-pylon configuration for drag minimization. The results demonstrate that the strong shock on the initial pylon surface is nearly eliminated and the optimal nacelle position can b e obtained within less than ten iterations.