Evaluation of heat transfer effects in small turbochargers by theoretical model and its experimental validation

In the last few years, the effect of diabatic test conditions on compressor performance maps has been widely investigated leading some Authors to propose different correction models. The aim of the paper is to investigate the effect of heat transfer phenomena on the experimental definition of turbocharger maps, focusing on compressor performance. This work was developed within a collaboration between the Polytechnic School of the University of Genoa (Italy) and the testing center CRITT M2A (France). In particular, an original model for the correction of compressor steady flow maps is presented and discussed. The major benefit of this method is represented by the easiness of data post-processing, the data base economy, the reduced number of geometrical and physical input parameters required and the accuracy of the solution. Besides, this model does not need an out-of-standard test bench to obtain the compressor maps. In the paper, experimental tests under quasi-adiabatic conditions developed to validate the proposed model are reported. A satisfactory agreement between measured and calculated compressor maps is highlighted.