Enhanced Lattice Boltzmann modelling of axisymmetric flows

Abstract

An enhanced axisymmetric Lattice Boltzmann fluid simulation model developed by the second author involves no calculation for velocity gradients and has the feature that all external force terms can simply be added to the model. In this paper, the model is extended and applied to investigate the characteristics of two complex axisymmetric flows for further assessment of its capability. First of all, Taylor–Couette flow for Newtonian and non-Newtonian fluids is considered. The combined effects of the Reynolds number, the radius ratio and the power-law index n on the flow characteristics are analysed for an annular space of finite aspect ratio. Different forced axisymmetric laminar cold-flow jets are then taken into account with different values of forcing amplitudes in the jets. The numerical results are compared with existing numerical results and experimental data reported in the literature to demonstrate the accuracy of the model.