Optimized design of axial compressor blades

A numerical optimization program based on a gradient method has been developed. Furthermore, in conjunction with a program for solving three-dimensional viscous flow fields a three-dimensional aerodynamic optimized design was conducted of transonic compressor rotating blades with the aim of maximizing the adiabatic efficiency. First, a chord-wise sweep optimization design was performed with an increase in adiabatic efficiency amounting to about 0.65% being achieved. Then, an optimization design was conducted to the camber line of the blade profile, thus obtaining the final blade. As compared with a prototype blade, the adiabatic efficiency can be enhanced by as high as 1.05%. It has been found that a swept blade alone can bring about only a rather limited improvement in aerodynamic performance. A combined optimization design involving both a chord-wise sweep and a camber line can lead to a significant improvement in flow conditions in a blade row and also a fine off-design performance.