Unstructured adjoint method for Navier-Stokes equations

For efficient aerodynamic design optimization, a discrete adjoint code is developed from an unstructured hybrid mesh Navier-Stokes solver. The adjoint code is verified by comparison of flux Jacobian and objective function gradient with a finite difference method. An aerodynamic design tool is developed utilizing the flow solver, adjoint code and a gradient-based optimizer and applied to a design example of a high-lift device. Use of prism layer grid sensitivities is suggested for more efficient gradient calculation from the adjoint analysis of Navier-Stokes equations with unstructured hybrid mesh.