DSMC Simulation of low Knudsen rarefied flows at micro/nano scales remains a big challenge for researchers due to large computational requirements. In this article the application of the simplified Bernoulli-trials (SBT)/dual grid collision scheme, newly proposed by Stefanov [1], is extended for solving low Knudsen/low speed and low Knudsen/high gradient rarefied micro/nano flows. The main advantage of the SBT algorithm is to provide accurate calculations using much smaller number of particles per cell, i.e.< N > ≈ 2, which is quite beneficial for near continuum DSMC simulations where the requirement of fine meshes faces the simulation with serious memory restrictions. Comparing the results of the SBT/dual grid scheme with the no time counter (NTC) and majorant frequency (MFS) schemes, it is shown that the SBT/dual grid scheme could successfully predict the thermal pattern and hydrodynamics field as well as surface parameters such as velocity slip, temperature jump and wall heat fluxes. Therefore, we present SBT/dual grid algorithm as a suitable alternative of the standard collision schemes in the direct simulation Monte Carlo (DSMC) method for typical micro/nano flows solution. Nonlinear flux-corrected transport algorithm (FCT) is also employed as a filter to extract the smooth solution from the noisy DSMC calculation for low-speed/low- Knudsen number DSMC calculations.

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