摘要
为了解车用增压器涡轮在脉冲进气条件下的性能,改善涡轮与发动机的匹配,采用数值模拟方法研究了径流有叶涡轮内部脉动流场。针对涡轮瞬时效率的计算,特别采用了相位平移方法。研究结果表明:由于涡轮级进口脉动气流的影响,涡轮流量和效率变化相对于压比均出现了滞后现象;脉动周期内转子进口攻角变化对叶轮内部速度场起主要影响作用;转子功率变化规律与涡轮级进口压力变化一致;适当提高涡轮设计流量能够增加涡轮有效利用发动机废气能量的能力。
For understanding well vehicle turbocharger turbine performance under pulsating flow condition to matching better with engine, the unsteady flow field in nozzled radial turbine was investigated by numerical simulation, especially using phase shift method to compute the turbine instant efficiency. Results show that both turbine mass flow and efficiency characteristics are of unusual ＂hysteresis＂ to the pressure ratio under pulsating flow intake condition. Rotor incidence variation in pulsating cycle influences strongly velocity field in turbine passage. Rotor power variation rule corresponds to that of the turbine inlet pressure. Increasing turbine design flow rate properly is beneficial to increase of turbine ability to utilize engine exhaust energy
出处
《内燃机工程》
EI
CAS
CSCD
北大核心
2013年第4期64-70,共7页
Chinese Internal Combustion Engine Engineering
