Multi-objective shape optimization of transonic compressor cascade at the same inlet Mach number

Abstract

ABSTRACT In this paper, a two-dimensional transonic cascade of German Aerospace Center (DLR) was redesigned with multi-objective optimization. The aerodynamic performance of the cascade was optimized with inlet Mach number of 1.1 by using the blade design method with thickness distribution superposed on the camber line. The non-dominated sorting genetic algorithm, (NSGA) II multi-objective optimization algorithm, was used to determine higher performance cascades. Cascade optimization was carried out within a unique inlet Mach number by varying the shapes of both the camber line and the thickness distribution curve. To enable the cascade to operate under specific conditions, we used an inlet Mach number control loop (IMCL) to regulate the outlet boundary conditions. Optimization was conducted to minimize the cascade total pressure loss coefficient under the three inlet conditions. The optimization results indicated that the total pressure loss coefficient can be reduced by 22% under the design condition, and the range of working conditions was widened.