Experimental and Numerical Study of an on-Engine Turbocharger Performance under the Inlet Pulsating Flow

The present work is focused on the performance analysis of a 1.7 liter engine with turbocharger. The ultimate target is studying the response of the turbocharger to the inlet pulsating flow. Such numerical analysis requires the time variation of pressure and velocity at turbine inlet. In order to achieve such information, one dimensional unsteady viscous compressible flow within a 1.7 liter turbocharged SI engine is modeled. It is also necessary to validate the results of simulation by experimental results. A test setup of the turbocharged engine on dynamometer is prepared and various performance parameters are measured at 12 different engine speeds. The comparison between experimental and simulation results shows a very good agreement. In fact, while the mean values of static pressure and temperature at various stations in both experimental and computational approach are fitted fairly on each other, but the amounts of instantaneous parameters are obviously a little bit different. One of the possible sources of errors is the characteristics maps of the turbocharger supplied by the manufacturer which are usually measured at steady operation of turbochargers. The results obtained in the present report will be used in simulating three dimensional unsteady compressible flow in turbocharger turbine which will be reported very soon.