Stochastic molecular modeling the transport coefficients of rarefied gas and gas nanosuspensions

Abstract

The subject of this paper is the stochastic molecular modelling of the transport coefficients for rarefied gases and gas nanosuspensions. The proposed method is an alternative one to the molecular dynamics method. However, unlike the latter, the phase trajectories of the molecular system are simulated stochastically. Adequate integral characteristics of the studied system are obtained by averaging the calculated data over independent phase trajectories. The efficiency of the proposed algorithm is demonstrated by calculation of the diffusion and viscosity coefficients of several noble and polyatomic gases and rarefied gas nanosuspensions. The modeling accuracy increases when a greater number of molecules and phase trajectories are employed.

Modeling the rarefied gas thermal conductivity in nanochannels

“…On the one hand, it is necessary to verify this method, calculating the transport coefficients in the bulk, and on the other hand, in nanochannels themselves. Previously [23][24][25][26], the efficiency and accuracy of SMM method were demonstrated, calculating the coefficients of self-diffusion, diffusion, and viscosity of rarefied gases, including polyatomic gases. In all cases, it is possible to achieve an accuracy of 1-2% using a relatively small number of molecules.…”

“…Previously, the authors developed the method of stochastic molecular modeling (SMM) for simulation of the transport coefficients of rarefied gases [23][24][25][26]. This method has been used to simulate the coefficients of self-diffusion, diffusion and viscosity of various gases, including polyatomic and rarefied gas nanosuspensions with high accuracy [26] (with the accuracy of experimental measurements). The viscosity of rarefied gases in nanochannels was also studied [27] and its anisotropy was established.…”

Molecular simulation of thermal conductivity of rarefied gas nanosuspensions

“…This method is intended, in particular, for calculating the transport coefficients in rarefied gases, their mixtures and gas nanosuspensions not only in the bulk, but in nanochannels of various shapes and porous media, for which it is difficult to solve the kinetic equation. In particular, using this method, the effective viscosity of rarefied gas nanosuspensions of Cu2O in nitrogen, Zn in neon and U in hydrogen were simulated [15].…”