Octant flux splitting information preservation DSMC method for thermally driven flows

We present the octant flux splitting DSMC method as an efficient method for simulating non-equilibrium flows of rarefied gas, particularly those arising from thermal loading. We discuss the current state-of-the-art flux splitting IP-DSMC technique and show that it fails to capture the shear stresses created by thermal gradients. We present the development of the octant flux splitting IP-DSMC as well as degenerate 2D, 1D, and 0D forms and apply the method to a number of problems including thermal transpiration, with satisfactory results.