Coupled Optimization of the Flow Field for a High-pressure-ratio Compressor Based on Extended Design Space

Self-recirculating casing treatment (SRCT) is widely used to improve the flow stability of high-pressure-ratio compressor (HPRC). However, the stability enhancement is usually compromised by associated flow losses. An optimization method for simultaneously expanding stability and enhancing performances of HPRC is proposed. By considering the SRCT-impeller coupled effect and the nonlinear blade leading edge, the original design space is expanded, then the existence of an optimal physical solution is ensured. Using the gradient mutation hybrid optimization algorithm for multi points optimization, the challenge of rapidly obtaining optimal physical solution is overcome. The results show that the total pressure ratio of the optimized compressor improves by ۱۱.۹۷%, ۸.۸۶% and ۷.۵۴% at the large flow rate, the design and the near-stall conditions, respectively. The isentropic efficiency increases by ۲.۸۷, ۲.۲۱, and ۱.۰۶ percentage points under the corresponding conditions. The stable operating range widens by ۱.۳ percentage points.  Based on the Sobol sensitivity analysis, and the comparative analysis of the flow field-geometry before and after optimization, the flow mechanisms of stability expansion and performance improvements of the compressor are comprehensively analyzed.

کلیدواژه ها:

High-pressure-ratio compressor ، Self-recirculating casing treatment ، Multi-component coupled optimization ، Stability & performance improvement ، Flow mechanism analysis