Aerodynamic design and optimization of a high-loaded axial fan stage using a curvature control method

Abstract

This study designs and optimizes a high-loaded transonic fan stage using a curvature control method. A fan stage with a total pressure ratio of 2.49 and adiabatic efficiency of over 87 % at the design point is obtained after 3D optimizations. The geometric curvature of the blade passage has important driving and adjusting effects on the mainstream and on the flow in the boundary layer. The reasonable optimization of camber line curvature can weaken the radial secondary flow on the blade surface and decrease shock losses effectively. It can also postpone or suppress boundary layer separation by reorganizing aerodynamic load. Hence, secondary flow losses are reduced, and the overall stall margin is expanded. This method features high precision, high operability, and short design cycle, hence providing highloaded fans/compressors with new freedom to improve design ability and offering new possibility to design system development.