Lattice boltzmann simulation of gas micro-flows in transitional regime

In this paper, gas micro-flows in transition regime havebeen investigated by lattice Boltzmann method (LBM). On the basis ofexisting LBM models for micro-flows simulation, the velocity correctionfunction for Knudsen layer was introduced into the model. And theappropriate expression of velocity correction was chosen with the suitableparameter according to the kinetic theory. In the treatment of boundarycondition, to avoid the difficulties posed by computing the higher-orderderivatives of the velocity, we took a substitute approach of higher-orderslip scheme to capture the slip velocity in transitional regime. The presentresults of two types of micro-flows agree well with the numerical solutions,and are evidently better than those with the former LBM simulations,especially in the case of Kn>0.5.