A turbocharger is commonly used to get more available output power for internal combustion engines. The radial turbine recovers the engine exhaust gas energy and converts it into rotational energy. The turbocharger turbine consists mostly in a radial or mixed flow impeller and a volute. The turbocharger volute transforms a part of the engine exhaust gas energy into a kinetic energy and guides the movement towards the rotor inducer at a suitable flow angle. The main purpose of this paper is to study the flow structure within a vanned volute of a mixed flow turbine. For this end, numerical simulations are conducted by solving the Navier-Stokes equations using the commercial Computational Fluid dynamiX (CFX) package and including a finite volume discretization method. The reasonable agreement found between experimental and numerical results of the turbine performance confirms the accuracy of the numerical model. The distributions of the pressure, the velocity, and the turbulence characteristics are numerically obtained in this analysis. The results showed that the fluid flow within the turbine volute is highly turbulent. Moreover, a significant pressure damp has been recorded within the volute vane which leads to a low-pressure flow at the rotor entry. Also, it has been shown that the flow direction considerably turns from the radial direction to the tangential one across the volute casing.
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