Numerical study of a turbulent jet flow issued from lobed diffuser

Abstract

Numerical simulations of turbulent free jet issuing from a six-lobed diffuser, using the shear stress transport k-ω model have been carried out. The three-dimensional calculations have been done on a tetrahedral mesh with 1.7 million cells. The numerical predictions have been compared with PIV measurements. This comparison shows reasonable agreement, principally, in terms of centreline longitudinal velocity, volumetric flow rate, longitudinal mean fluctuating velocity and streamwise vorticity. With these results, the shear stress transport k-ω model can be considered for future studies as an efficient mean for quickly optimizing lobed diffuser design and analyzing exit Reynolds number effect on the mixing performance of this three-dimensional flow for HVAC application.