Transient Performance of Automotive Turbochargers: Test Facility and Preliminary Experimental Analysis

Experimental investigations on automotive engine intake and exhaust components are fundamental to achieve a better understanding of their behaviour both in steady and transient operation. To this purpose a dedicated test facility, particularly suited for the evaluation of exhaust turbochargers performance, has been operating at the University of Genoa (ICEG). In the paper a new arrangement of the testing circuit and of the relevant measuring system is presented. At the conclusion of the plant setup a first investigation on a typical automotive turbocharger for spark ignition application was developed. After measuring compressor and turbine steady flow curves in a wide operating range, the attention was focused on unsteady flow phenomena in the exhaust subsystem when using the two pulsating flow generators available on the test rig. The relevant results are presented in the paper referring to measured pressure diagrams. In particular, the effect of the turbine feeding circuit geometry and of the turbocharger regulating device is analysed and discussed.