Aerodynamic Optimization Design And Analysis Of Axial Compressor

Advanced turbine engine system requires high-performance fan/compressor, whose aerodynamic design methodology and tools are essential and sufficient to meet this demand. Aerodynamic optimization design based on viscous 3D numerical simulation has been a maturely analytical tool, and optimization design plays a more and more important role in modern design practice. In the present dissertation, the multi-objective optimization design was carried out on the transonic compressor stage of a typical aeroengine, in order to improve the aerodynamic performance including total pressure ratio, isentropic efficiency and stable mass flow region. Several key factors that affect the improvement of aerodynamic performance are investigated in the same time.The aerodynamic numerical optimization platform employed here can be divided into three modules:parameterization and fitting of blades; simulation of flow field; optimization strategy. As to the aerodynamic optimization design is non-linear, multi-variable and multi-objective, it uses the integrated optimization strategy which includes artificial neural network (ANN) and genetic algorithm (GA). Artificial neural network is a mathematical model that is inspired by the structure and functional aspects of biological neural networks, and used as an approximate model to lessen the size of CFD operation through modeling complex relationships between inputs (parameters) and outputs (flow field evaluation) in the present platform. Genetic algorithm is a stochastic probability search method based on the mechanism of natural evolution. It can find the globally optimal solution in theory.The optimization results demonstrate that the optimization platform is effective and efficient. Stacking line optimization and 3D optimization are carried out to investigate the effects of stacking line and 2D profile on loss mechanisms in transonic compressor, respectively. Based upon the analysis, measures are taken into account to further improve the compressor performance. Design cases are selected to propose the viewpoints of guidance, such as sweep and lean, which are helpful for the design of compressor in the future.