Investigation of Temperature-dependent Viscosity Effect on Thermal Non-Newtonian Fluid Flow over a Square Cylinder by Lattice Boltzmann Method

In the present study, the non-Newtonian fluid flow with the temperature-dependent viscosity over a non-isothermal square cylinder is investigated. Carreau-Yasuda model is utilized to simulate the non-Newtonian properties of the fluid. Non-Newtonian Lattice Boltzmann method, with local computing features, is used to numerical simulate of momentum and energy equations. Grid analysis and validation of results have been successfully completed. Simulations are accomplished for a wide range of parameters including Reynolds number 10< Re < 50, Non-Newtonian index 0.3< n <1, and temperature-thinning index 0< b < 0.5. Simulations show that the proposed method is able to predict the shear- and temperature-dependent properties of Carreau-Yasuda non-Newtonian fluid flow. The results show that increasing of temperature-thinning index leads to reduction and increment of the drag coefficient and Nusselt number, respectively.