车用增压器离心压气机改型设计

为缩短研制周期,提高设计成功率,降低研制风险,基于当代工具预测设计方法,开展了某车用增压器跨音速离心压气机设计和试验验证。研究结果表明:压比3为亚音和跨音速临界压比,高于此临界压比,叶轮进入跨音速流动,流量范围急剧变窄;压比大于4,流量范围不高于20%,需采用机匣处理等流量拓宽装置以获得宽广压气机特性;采用机匣处理装置后,跨音速流量范围可拓宽15%左右;采用两区模型性能预测技术和控制载荷叶片造型技术可获得高压比宽流量范围的高性能压气机。

Design Improvement of Centrifugal Compressor for Vehicle Turbocharger

The transonic centrifugal compressor design and experiment for vehicle turbocharger were carried out based on modern predictive design tools to realize the goal of short design period,high design success rate and low development risk.The results show that the value 3 is the critical pressure ratio between subsonic and transonic.When the pressure ratio is beyond 3,the flow inside impeller is in transonic state and the stable operating range narrows quickly.When the pressure ratio is beyond 4,the stable operating flow range will not exceed 20%,which demands flow extending device like casing treatment to acquire the better compressor performance.Using the casing treatment device,the stable operating range of transonic flow can be extended by 15%.In addition,high performance compressor with high pressure ratio and broad stable operating range can be acquired by using the technologies of two-zone model performance prediction and load controlling blade shaping.