Numerical study of turbulent separated flows in axisymmetric diffusers based on a two-fluid model

Abstract

This paper discusses a numerical study of turbulent flow at Re = 1.56×104 in an axisymmetric diffuser with half-angle expansion α=14°, 18° и 90°. The results obtained are compared with known experimental data. The flow at the diffuser inlet is fully developed turbulent. To simulate the flow, a relatively recently developed two-fluid turbulence model in the Comsol Multiphysics software package was used. The paper also presents numerical results of the well-known SST and SA turbulence models, which are included in the Comsol Multiphysics software package. It is shown that the two-fluid turbulence model in the Comsol Multiphysics software package is capable of producing more accurate results than known models. In addition, it demonstrated good convergence and stability.

Keywords

• two-fluid model
• navier–stokes equations
• separated flow
• axisymmetric diffuser