Comprehensive analysis on the effect of asymmetric heat fluxes on microchannel slip flow and heat transfer via a lattice Boltzmann method

Lattice Boltzmann method is adopted to explore the hydrodynamic and thermal behaviors for mixed slip convective flow in a horizontal microchannel. The asymmetric wall heat fluxes are employed and the slip boundary conditions according to the consideration of the range of Knudsen number are also utilized on the top and bottom walls, correspondingly. Besides, the effects of wall heat flux ratio, Knudsen number and mixed convection parameter on the flow and heat transfer are analyzed, especially for the influence of the entrance region. Numerical results show that the thermal conversion strength in the inlet regime is extremely sensitive for the variation of three influencing factors, especially for the top wall. The asymmetric wall heat fluxes seriously affect the uniformity of the temperature field in the entrance region. Moreover, the buoyancy force results in the generation of a vortex near the top wall at a lower Knudsen number and further affects the friction coefficient and heat transfer.