The Influence Of Interstage Cooler On The Performance Of High Pressure Stage Compressor In The Two-stage Turbocharged System

Interstage cooler not only change the high pressure stage compressor inflow condition,impacting on the performance of the high pressure stage compressor, but also produce a greateffection on the work efficiency for the whole two-stage turbocharged system. Therefore, theresearch on the influence of interstage cooler on the performance of high pressure stagecompressor is profound theoretical significance and practical significance, it provides theorybasis for the research and design of high and ultrahigh pressure ratio of the two-stageturbocharged system. The main research contents are as follows:This paper chooses the high pressure stage compressor impeller and volute as theresearch object, sets up its calculation model using CFD method, uses one equationturbulence model and disperses N-S equation using the finite volume method; After thecalculation model is completed, the grid independent solution is validated in this paper, rulingout the influence of grid number on calculation results; By comparing with the experimentaldata, the calculation model is verified that its model and setting up is correct and reasonable.On this basis, Flowfield of high pressure stage compressor were analyzed, including theinternal flow of impeller and volute. Through studying the velocity and static pressuredistribution on the surface of different height Blade-to-Blade, the hub and the shroud, thepaper summarizes the flow characteristics of impeller and damage mechanism; From thetransverse section and circumferential section of volute, the paper respectively study its speed,static pressure, vorticity and total pressure recovery coefficient, analyze the distribution ofvelocity and pressure and internal loss distribution of volute.The paper explores the effection of interstage intercooler on the properties of highpressure stage compressor by changing different inlet state. Mainly from the following severalaspects: interstage intercooler influence on the high pressure stage compressor characteristiccurve, interstage intercooler effect on the outlet entropy distribution in the impeller, interstage intercooler impact on the efficiency of the impeller exit, interstage intercooler impression ofcircular rector distribution inside the volute, interstage intercooler effects on total pressureloss distribution inside the volute. Among, the different inlet condition including: differentimpeller speed (50000[Rev min^-1],90000[Rev min^-1],110000[Rev min^1]), different inlettotal temperature (333[K],343[K],353[K],363[K],373[K],393[K],423[K]), and differentinlet total pressure (150kPa,180kPa,200kPa,220kPa,250kPa,300kPa).The results showed that with the increase of impeller speed, high pressure stagecompressor pressure ratio increase, flux increase, performance curve steepened; With theincrease of inlet total pressure, high pressure stage compressor pressure ratio increase, theisentropic efficiency curve to the big flow direction as a whole, impeller entropy increase, theefficiency is lower, the volute total pressure recovery coefficient reduece, loss of the voluteincrease; With the increase of the inlet total temperature, the pressure ratio decreases, andisentropic efficiency curves shift to the small flow direction, impeller entropy decrease,efficiency is higher, the internal total pressure recovery coefficient increases, the loss ofvolute reduce.