TY - JOUR T1 - A Localized Mass-Conserving Lattice Boltzmann Approach for Non-Newtonian Fluid Flows JO - Communications in Computational Physics VL - 4 SP - 908 EP - 924 PY - 2018 DA - 2018/04 SN - 17 DO - http://doi.org/10.4208/cicp.2014.m303 UR - https://global-sci.org/intro/article_detail/cicp/10983.html KW - AB -

A mass-conserving lattice Boltzmann model based on the Bhatnagar-Gross-Krook (BGK) model is proposed for non-Newtonian fluid flows. The equilibrium distribution function includes the local shear rate related with the viscosity and a variable parameter changing with the shear rate. With the additional parameter, the relaxation time in the collision can be fixed invariable to the viscosity. Through the Chapman-Enskog analysis, the macroscopic equations can be recovered from the present mass-conserving model. Two flow problems are simulated to validate the present model with a local computing scheme for the shear rate, and good agreement with analytical solutions and/or other published results are obtained. The results also indicate that the present modified model is more applicable to practical non-Newtonian fluid flows owing to its better accuracy and more robustness than previous methods.