Effect of Swirl on the intake of Turbocharger 2008-28-0069

Turbochargers are being used as an integral part in diesel engines to reduce the pollution on one hand and to improve the performance at low engine speed on the other hand. The intake of the turbocharger is of annular diffuser type. The present work is intended to explore the aerodynamics of axial annular diffuser with the help of 2D axisymetric turbulence kinetic energy (k) and its dissipation rate (ε) computational fluid dynamics (CFD) model. The behaviour of subsonic turbulent flow of air inside the annular diffuser with central cylindrical hub and diverging casing has been analyzed. The analysis has been carried out with experimentally validated model for various inlet swirl velocity profiles. The development of the shape of velocity profiles at various transverses of diffuser passage and region of flow separation and its effect on the performance of diffuser with regards to pressure recovery coefficient, diffuser effectiveness and diffuser loss coefficient is predicted which agrees reasonably well with the available data.