Computational Method Research On The Performance Curve Of Radial Turbochargers

The turbine performance curve which shows the function relations among the primary parameters during the turbine works is an important basis to charge if the engine matches the turbine well or not. This paper conducted research work on computational method of turbine performance curve which is based on the turbine inlet and outlet parameters. The gas condition equations set is used to simulate the turbine interior flowing process and then the turbine performance curve is generated.At the beginning of this paper, the turbine performance of radial turbocharger and its regular methods are discussed. To get the inlet and outlet parameters of air compressor and turbine, WD615 diesel engine is carried on the engine and turbocharger's match experiment. Based on this experiment, the performance parameters under various working conditions are obtained and these parameters are the basis for the further turbine performance's thermodynamics computation. Combined with structure parameters of J90 turbocharger's turbine wheel, the theoretical research has been conducted according to the turbine performance curve's computational method and the feasibility is discussed by comparison with the experiment results. First, the boundary conditions of volute and spray nozzle structures are always simplified; second, the flow and loss of turbine impellers is analyzed and studied. Third, using programming language of MATLAB and VBA, gas state equations of turbines are programmed and calculated. At the same time, the turbine performance curves are obtained. Finally, to ensure the accuracy, through the union tentative data, the analog computation of these three engines and turbochargers'entire prototype matching is conducted separately by applying software AVL-BOOST and GT-POWER which are used in simulating engine and the turbocharger matching. First, using a simple model, turbine performance curves are calculated. Then, turbine curves are applied to software. Through combined test data, full model matching of three engines and Turbochargers are simulated. The result has a certain accuracy.This paper uses the turbine performance curve computational method which applies into the CFD software turbocharger's entire prototype matching. Compared with experimental results, this method has definite feasibility. And that means it is provided a simple and effective way on research of turbine performance curves.