Direct Simulation Monte Carlo (DSMC)

Direct Simulation Monte Carlo (DSMC) method is a stochastic approach for solving the Boltzmann equation. In this approach, a representative set of particles is chosen, which move and collide over the computational domain and occurrence of collision is decided using probabilistic models. Use of the DSMC method is particularly useful for rarefied gas flows, where the mean free path of molecules becomes comparable to characteristic length scale.

SankhyaSutra’s DSMC solver is extensive and supports various collision models, viz. hard sphere and variable hard/soft sphere and boundary conditions. Highly optimized parallel software implementation allows our solver to handle large problems efficiently. Our solver has been extensively validated using benchmark problems.

For example, for the benchmark problem of incompressible flow in a lid-driven cavity, we note a close match between the velocity profiles at the centreline obtained using SankhyaSutra’s DSMC solver and corresponding results reported by Ghia et al. (Comp Phys, 48, 387, 1982). For the compressible flow in a lid-driven cavity, we compare results obtained using SankhyaSutra’s DSMC solver with those derived using Sparta software package. Our solver provides similar results as Sparta, while requiring approximately half the computational time. 

Direct Simulation Monte Carlo for Incompressible Flow
Lid Driven Cavity (Incompressible flow): Re = 1000, Ma = 0.2, Kn = 0.0002 (Comparison with Ghia et al, Comp Phys, 48, 387, 1982) Direct Simulation Monte Carlo
Direct Simulation Monte Carlo for Compressible Flow
Lid Driven Cavity (Compressible flow): Re = 110, Ma = 1, Kn = 0.011 (Comparison with Sparta) Direct Simulation Monte Carlo