Modelling of Supersonic and Subsonic Flows Using Hybrid Pressure-Based Solver in Openfoam

Abstract

In this paper, validation of the hybrid central solver based on PIMPLE algorithm and KT scheme (rhoPimpleCentralFoam-solver) for high and low speed flows has been presented. Two different test cases were considered for the present study; a supersonic flow over a backward facing step with Mach number 2 and non-reacting subsonic flow separated by a bluff body with a Mach number 0.18. Backward facing step test case was studied using SST k-ω turbulence model, whereas performance of three different RANS based turbulence models, i.e. SST k-ω model, standard k-ε model and modified k-ε models were assessed for the flow over a bluff body. Results obtained from hybrid central solver for backward facing step using SST k-ω turbulence model showed good agreement with the experimental data. The mean flow features such as expansion fan, recirculation zone, boundary layers, shear layer and reattachment shock were also captured accurately. Whereas, the performance of the modified k-ε turbulence model was found to better as compared to other turbulence models in the predictions of flow structure of flow over a bluff-body.