Stirred tank simulation using Partially-Averaged Navier-Stokes $$k_u-\epsilon _u$$ k u - ϵ u turbulence model

Abstract

Abstract In the present study, simulation of a stirred tank using axial flow impeller has been studied numerically to see the behaviour of flow variables in the entire vessel. It is assumed that the flow is steady state, two dimensional, incompressible and axisymmetric. For simulation, Partially-Averaged Navier-Stokes (PANS) $$k_u-\epsilon _u$$ k u - ϵ u turbulence model has been taken into account. For discretization, control volume method along with upwind and power-law schemes have been taken. The solutions are obtained by using the SIMPLE algorithm. The boundary conditions for impeller are given by using the experimental data. The main objective is to investigate the influence of different filters width $$f_k$$ f k of the PANS $$k_u-\epsilon _u$$ k u - ϵ u model parameter on the characteristic flow variables. The predicted results of the PANS $$k_u-\epsilon _u$$ k u - ϵ u model for different $$f_k$$ f k have been compared with the experimental data at different axial levels of the stirred tank. It has been observed that the power-law scheme gives better agreement with the experimental data. Further, near the impeller region, PANS predicted results are better for smaller $$f_k$$ f k . Also, Reynolds-Averaged Navier-Stokes Shear Stress Transport (SST) $$k-\omega $$ k - ω turbulence model has been tested for comparative study.

Keywords

• PANS $$k_u-\epsilon _u$$ k u - ϵ u turbulence model
• SST $$k-\omega $$ k - ω turbulence model
• Control volume method-Stirred vessel
• Axial flow impeller