弯管进气对离心压气机效率的影响

Effects of curved tube intake on centrifugal compressor efficiency

对弯管进气的离心压气机进行数值模拟计算,通过与直管进气试验和数值模拟结果的分析对比,研究弯管对离心压气机效率的影响,分析在3种不同形式的弯管进气条件下压气机效率的变化。研究结果表明:弯管进气时压气机效率有所降低,不同形式的弯管进气对压气机效率的影响不同。在恒定转速小流量工况下,弯管与直管进气压气机效率相差较小,随着流量的增加,弯管进气与直管进气压气机效率差值逐渐增大;当转速不同时,弯管进气造成叶轮进口严重的气流不均匀流动,使效率下降,高速大流量工况效率下降最为明显,其中普通90°弯管进气效率最大降幅为7%。

The numerical simulation of centrifugal compressors with curved tubes intake is performed,the effects of curved tubes on the efficiency of centrifugal compressors are studied by comparing and analyzing with the results of experimental and numerical simulations of straight tube inlets.The results of numerical simulation show that the compressor efficiency will decrease with the intake of curved tube,different forms of curved intake tubes have different effects on compressor efficiency.At a constant speed,the efficiency difference is quite little between the curved tube and straight tube intake.As the flow rate increases,the efficiency of the compressor with the intake of curved tube gradually decreases compared to the straight tube inlet.The curved tubes intake causes serious uneven airflow at the impeller inlet,which reduces the efficiency.The efficiency drop is highest in the case of high-speed and large flow.The maximum drop in the efficiency of ordinary 90°curved tube intake can reach 7%.