Optimization of the hole exit shape of the vortex generator jets in a compressor cascade

Abstract

Vortex generator jets usually use a circular hole. The hole exit shape is also an important parameter, so the change of the shape will have a significant influence on the control effect of the compressor. In this article, the optimization design of the hole exit shape is studied in order to find the optimal geometry. The 2D hole exit shape is represented with a binary coded and initialized with the B-spline. The surrogate-based optimizer consists of a parametric design code, a computational fluid dynamics solver, a Kriging model, an infill sample criterion, and a genetic algorithm. First, the design of the symmetric hole is studied in a low ratio of the jet to inlet mass flow. The circumferential length of the designed hole is fixed. Second, both the symmetric hole and the asymmetric hole are studied. And the area of the hole exit shape is fixed. The results show that the optimal hole shape can enhance the strength of the jet vortex and reduce the total pressure loss of the compressor cascade. A better control effect can also be obtained in a high jet mass flow.