Prediction of a turbocharger performance under pulsating flow by construction of an unsteady one-dimensional flow analysis model

In recent years, because of the energy crisis, improving the thermal efficiency of automobiles has become a very important issue. It is known that a pulsating flow generated by engine valves affects the performance and efficiency of the turbocharger adversely [1]. However, the turbocharger characteristics under pulsating flow have not been clarified to a satisfying degree yet, and no prediction method of turbocharger performance has been established yet. In this study, an unsteady one-dimensional flow model of a turbocharger is constructed by modeling the physics of aerodynamic loss and unsteady characteristics based on experiments and 3D-CFD. Furthermore, the characteristics of the turbocharger under pulsating flow were predicted using the built one-dimensional unsteady flow model. Moreover, this one-dimensional model was implemented in GT-Power which is a one-dimensional commercial code used by many automobile companies.