Variance-reduced DSMC method for axial-symmetric flows of gaseous mixtures

Abstract

A variance-reduced DSMC method is presented for the simulation of axial-symmetric flows of gas mixtures, which are described by the McCormack linearized kinetic model. The one-dimensional kinetic equation is solved by the variance-reduced DSMC method. The distribution function of the molecular velocity is modeled by positive and negative particles. Weighting zones are introduced in order to handle the cylindrical symmetry of the problem. Pressure driven flows of noble gas mixtures and a single gas through a tube are simulated in order to analyze the method. The results are compared to the discrete velocity solution of the kinetic problem. A good agreement is found between the results provided by the two approaches. An equivalent standard DSMC simulation is also performed to test the computational performance of the methods. It is demonstrated that the present variance-reduced DSMC provides a more efficient simulation for low speed flows than the standard DSMC.