Transonic Compressor And Low Speed Fan Blade Inverse Design Optimization Technology Research

For improve thrust loading and decrease fuel consume of the engine, propulsive system of the future demand the compressor in possession of higher pressure ratio and more efficiency. For achieve this purpose, pressure ratio and efficiency of one stage of compressor need to be improved, according to the aerodynamic request, new design method of blade profile and cascade should be developed.The design method proposed in this paper is, in principle, based on the potential-stream function inverse method, using numerical optimization to obtain optimized blade profiles. In inverse profile design, they give designers big challenges that the ideal velocity distribution is hard to obtain and sometimes the result can not meet the geometrical demand, such as double covering of flow field or unclosed profiles, would come out. A suit of optimization program have been designed, through the influence disciplinarians research of velocity distribution of blade surface and the shape of blade profile, optimization blade profile have been obtained through adjust the velocity distribution available.In this paper, a quasi-irrotational equation is used to describe the flow in cascade instead of the generally used irrotational equation. Then a Laplace equation can be deduced and through computation, the blade profile coordinates and geometry of the cascade results from an analytical solution. Next, an optimization method, taking the geometry parameters of the unclosed profile as its objective functions, is used to obtain an optimized blade profile. And last, the optimized profile is refined with round arcs added in the leading and trailing edges. In the design procedure, the presented method in the paper shows its applicability and effectiveness, especially for modification of the proscribed velocity distribution.In the process of inverse blade profile designing, a nonlinear algorithm of velocity distribution optimization, different optimize methods was researched , according to the difference of suction and pressure surface, this technique can adjust the thickness of blade profile available. The incidence angle and deviation angle cangive freely in the process of blade profile design; the satisfied blade profile can get through velocity distribution optimization.In this paper, many blade profiles have been designed to examine the method. according to result, the method proposed in this paper can adjust the velocity distribution of blade profile available, reduce lots of manual control factors, developed and improved the technique of blade profile design.