The introduction of a tilted volute design for operation with a mixed flow turbine for turbocharger applications

This paper introduces a tilted volute design for operation with a mixed flow turbine rotor. CFD results show an efficiency gain of up to 1.2% over the standard radial design at the highest tested turbine rotational speed. The efficiency gain was found to be the result of a reduction in separation from the blade suction surface. A reduction in the flow cone angle was also observed for the tilted housing, as a result an increase in negative incidence angles at the blade LE was observed. This work shows that optimization of the turbine housing specifically for mixed flow applications can yield significant performance benefits.