Wall boundary conditions for the macroscopic equations,i.e.the NSF(Navier-Stokes-Fourier)equations,R13/R26 moment equations,lose their accuracy dramatically and are easy to diverge,especially in the middle and high Knudsen number regimes.To overcome these difficulties,a wall boundary condition for the R13/R26 moment method was proposed at the mesoscopic level.The velocity distribution function was reconstructed and feedback into the Boltzmann model equation in the near-wall region,and the wall boundary condition for the R13/R26 moment method was calculated on the basis of solving the Boltzmann equation with the discrete velocity method.Results indicate that:the proposed wall boundary condition is able to increase the computational accuracy up to 59.84％compared with the classical approach.Meanwhile,it is able to get the steady-state solution for the Knudsen number up to 1.0.
维普
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