MULTIGRID ONE-SHOT METHOD FOR STATE CONSTRAINED AERODYNAMIC SHAPE OPTIMIZATION.

This paper presents applications of an optimization-based multigrid method to state constrained aerodynamic shape optimization problems. The one-shot simultaneous pseudo-timestepping method has been applied successfully to such problems, reducing the cost of computation up to 70% from that of a traditional gradient method. However, the number of optimization iterations is comparatively large in this method since we update the design parameters in each time-step of state and costate runs. In this paper we use an optimization-based multigrid strategy to reduce the total number of optimization iterations while keeping the idea of the one-shot pseudo-time-stepping method. Design examples of drag reduction with constant lift, together with geometrical constraints, for an RAE2822 airfoil are included. The total effort required for convergence of the optimization problem is between four and six times that of forward simulation runs depending on computational grid size. [ABSTRACT FROM AUTHOR]