Performance investigation of a turbocharger compressor

[摘要] ENGLISH ABSTRACT: Stellenbosch University participated in a project to re-design the compressorsection of a diesel locomotive turbocharger. Tests conducted on the prototypecompressor showed possible rotating stall in the diffuser section before thedesigned higher pressure ratio could be achieved. When approaching the higherpressure ratio, the compressor inlet trunk started to rhythmically collapse (dueto suction), the engine shook and bellows of black smoke were exhausted bythe engine. It was decided to simulate the prototype compressor's operationby using the 1-D theory of Aungier (2000) and to perform a 3-D CFD analysisof the compressor using FINE/Turbo of NUMECA International.A veri cation process was followed to show the accuracy of the 1-D and3-D modelling methods using two well-known centrifugal compressor test casesfound in the literature, namely the O-Rotor by Eckardt (1975, 1976, 1980) andthe Radiver open CFD test case by Ziegler et al. (2003c). Results from themodels were compared to available experimental results and the accuracy wasfound to be su cient to investigate the prototype compressor's impeller anddiffuser.Both prediction methods con rmed separation in the vaned di user acrossthe entire operatingow range of the prototype compressor at the design impellerspeed. The 3-D method identi ed supersonicow at the vaned diffuserinlet at the operating point and also predicted a smaller operating range thanoriginally anticipated. Both the 1-D and 3-D methods also predicted impellerblade stall over the entire operatingow range at the design impeller speed.A recommendation was made to redesign the impeller and diffuser of the prototypecompressor.

[发布机构] Stellenbosch University