Based On The Complex Shape Method Airfoil Optimization Design And Parallel Computing Research

An airfoil shape design method that couples viscous flow analysis, a complex method and parallel calculation is described in this paper. The method is applied to search an airfoil geometry with improved aerodynamic performance at single or multiple design-point while the specified design constraints being satisfied.The aerodynamic objective function is described as some aerodynamic parameters gained by Reynolds-averaged N-S equations, such as: the lift, the drag, the ratio of lift to drag or the pitching moment, etc. The optimum process is started by a base airfoil. The airfoil geometry is modified by adding a linear combination of Hicks and Henne functions. A series coefficients of shape functions are defined as design variables. The optimization problem can be described as the aerodynamic objective function and the design variables constrained by some parameters. Multi-objective optimization problem of this paper is transformed into a single-objective problem by weighting the objective functions of different design points. Then the objective function is improved by the complex optimum method and the most aerodynamically favorable geometry that be provided with the better aerodynamic performance is obtained.In order to improve the efficiency of the multi-point optimization problem, the parallel calculation basing on MPI is applied. Different CPU of the web is allocated to compute the flow field corresponded with the every design point, the parameters are transferred to the major CPU in which the optimum process is run.The flow is modeled with Reynolds-averaged N-S equations in order to gain reliable design results. Several optimum examples are presented that prove the complex optimum method in this paper runs efficiently and robustly. The parallel examples are presented that proved the parallel calculation is employed in the multi-point optimization problem successfully and the preferable efficiency is obtained. This method described in this paper can find its application in aircraft industry when it is employed to improve the aerodynamic performance characteristics of an existing baseline airfoil to meet specified engineering requirement.