Diffusion is a ubiquitous physical phenomenon where thermodynamic nonequilibrium effects(TNEs) are outstanding issues. In this work, we employ the discrete Boltzmann method to investigate the TNEs in the dynamic proce...Diffusion is a ubiquitous physical phenomenon where thermodynamic nonequilibrium effects(TNEs) are outstanding issues. In this work, we employ the discrete Boltzmann method to investigate the TNEs in the dynamic process of binary diffusion. The main features of the distribution function in velocity space are recovered and discussed.It is found that, with the decreasing gradients of macroscopic quantities(such as density, concentration, velocity, etc.),both the local and global TNEs decrease with the time but increase with the relaxation time in a power law, respectively.展开更多
基金Supported by the MOST National Key Research and Development Programme under Grant No.2016YFB0600805the China Postdoctoral Science Foundation under Grant No.2017M620757+1 种基金the Center for Combustion Energy at Tsinghua University,Natural Science Foundation of Hebei Province under Grant Nos.A2017409014,ZD2017001 and A201500111,FJKLMAA,Fujian Normal Universitythe UK Engineering and Physical Sciences Research Council under the Project UK Consortium on Mesoscale Engineering Sciences(UKCOMES)under Grant No.EP/L00030X/1
文摘Diffusion is a ubiquitous physical phenomenon where thermodynamic nonequilibrium effects(TNEs) are outstanding issues. In this work, we employ the discrete Boltzmann method to investigate the TNEs in the dynamic process of binary diffusion. The main features of the distribution function in velocity space are recovered and discussed.It is found that, with the decreasing gradients of macroscopic quantities(such as density, concentration, velocity, etc.),both the local and global TNEs decrease with the time but increase with the relaxation time in a power law, respectively.
