Unsteady flow modelling of a pressure wave supercharger

Abstract Pressure wave machinery constitutes a promising device in a wide variety of applications such as superchargers in automobile engines and topping devices in gas turbines. A very attractive feature is the built-in exhaust gas recirculation which provides a substantial reduction in NOx emissions of the engine. The present work presents a simple numerical model based on shock tube flow, accounting for viscous and thermal losses inside the rotor of the supercharger as well as leakage losses at the extremities of the rotor. It is validated against available experimental data of shock tube flow and on a three-port wave rotor, called a pressure divider. The model is then applied on a configuration suited for automobile engine supercharging. Comparisons with experimental data show that the present method can analyse the basic flow patterns inside the rotor, providing a useful tool for pressure wave supercharger flow predictions.