In this study, we use a hybrid direct simulation Monte Carlo (DSMC) and Navier-Stokes (NS) algorithm to solve rarefied flow over micro/nano scale flat plate and cylinder. DSMC and NS solvers operate in non-equilibrium and near-equilibrium regions independently and a state-based coupling (Dirichlet–Dirichlet boundary-condition coupling) is used to transfer information between the solvers. Hybrid DSMC-NS solution is compared with the full DSMC solution and it is shown that it accurately predicts heat transfer and velocity and temperature distributions in the flow field. We observed that the DSMC simulation of shock wave around the cylinder is not necessary for accurate prediction of surface properties. Simulation time of the hybrid solution shows 65% reduction for the cylinder flow.

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