Assessment of schemes for coupling Monte Carlo and Navier-Stokes solution methods

A planar Couette flow is simulated using several different interface conditions in a hybrid technique in which the direct simulation Monte Carlo (DSMC) method and the Navier-Stokes equations are coupled. Comparison of computational times and accuracy of the different methods are made to determine the best approach for further study. It is concluded that the Marshak condition, in which the properties at the interfaces between the continuum and rarefied regions are determined from flux conservation equations, is the best technique in terms of accuracy and run-time performance. When coupling NavierStokes and DSMC solvers, the use of a Maxwellian distribution to represent the particle velocity distribution hi the Navier-Stokes region yields unacceptable errors.