Turbomachinery profile design by an improved inverse method based on optimization technique

It is very important for gas turbine engineers to have better blade design method, especially for axial flow turbomachinery with high pressure ratio, and to increase mass flow rate. Based on the potential-stream function inverse method, a design method is proposed. By investigating the influence of prescribed velocity coefficient distribution on blade surface, it is found that the non-physical solution usually obtained by general inverse method could be avoided by adjusting the local velocity coefficient distribution. The object functions are set up for leading edge closing and trailing edge closing problems respectively for numerical optimization. The optimized blade profiles with satisfactory performance and reasonable geometrical shape can be obtained by this improved optimization method. Three examples of profile design give good results in terms of design precision, and wider application areas in turbine and compressor blade profile design could be developed.