Molecular kinetic modelling of non-equilibrium transport of confined van der Waals fluids

doi:10.1017/jfm.2023.893

CORC > 力学研究所 > 中国科学院力学研究所 > 高温气体动力学国家重点实验室

	Molecular kinetic modelling of non-equilibrium transport of confined van der Waals fluids
	Shan, Baochao 4; Su, Wei 2,3; Gibelli, Livio 4; Zhang, Yonghao 1
刊名	JOURNAL OF FLUID MECHANICS
	2023-11-24
卷号	976 页码:36
关键词	microscale transport kinetic theory
ISSN号	0022-1120
DOI	10.1017/jfm.2023.893
通讯作者	Zhang, Yonghao(yonghao.zhang@imech.ac.cn)
英文摘要	A thermodynamically consistent kinetic model is proposed for the non-equilibrium transport of confined van der Waals fluids, where the long-range molecular attraction is considered by a mean-field term in the transport equation, and the transport coefficients are tuned to match the experimental data. The equation of state of the van der Waals fluids can be obtained from an appropriate choice of the pair correlation function. By contrast, the modified Enskog theory predicts non-physical negative transport coefficients near the critical temperature and may not be able to recover the Boltzmann equation in the dilute limit. In addition, the shear viscosity and thermal conductivity are predicted more accurately by taking gas molecular attraction into account, while the softened Enskog formula for hard-sphere molecules performs better in predicting the bulk viscosity. The present kinetic model agrees with the Boltzmann model in the dilute limit and with the Navier-Stokes equations in the continuum limit, indicating its capability in modelling dilute-to-dense and continuum-to-non-equilibrium flows. The new model is examined thoroughly and validated by comparing it with the molecular dynamics simulation results. In contrast to the previous studies, our simulation results reveal the importance of molecular attraction even for high temperatures, which holds the molecules to the bulk while the hard-sphere model significantly overestimates the density near the wall. Because the long-range molecular attraction is considered appropriately in the present model, the velocity slip and temperature jump at the surface for the more realistic van der Waals fluids can be predicted accurately.
资助项目	Engineering and Physical Sciences Research Council[EP/R029598/1] ; UK Consortium on Mesoscale Engineering Sciences (UKCOMES) under the UK Engineering and Physical Sciences Research Council ; Computational Science Centre for Research Communities, through UKCOMES
WOS关键词	LATTICE BOLTZMANN MODELS ; HIGH KNUDSEN NUMBER ; EQUATION-OF-STATE ; BULK VISCOSITY ; MULTIPARAMETER CORRELATION ; ENSKOG EQUATION ; DENSE FLUIDS ; GAS ; DYNAMICS ; ARGON
WOS研究方向	Mechanics ; Physics
语种	英语
WOS记录号	WOS:001108909400001
资助机构	Engineering and Physical Sciences Research Council ; UK Consortium on Mesoscale Engineering Sciences (UKCOMES) under the UK Engineering and Physical Sciences Research Council ; Computational Science Centre for Research Communities, through UKCOMES
内容类型	期刊论文
源URL	[http://dspace.imech.ac.cn/handle/311007/93542]
专题	力学研究所_高温气体动力学国家重点实验室
通讯作者	Zhang, Yonghao
作者单位	1.Chinese Acad Sci, Inst Mech, Ctr Interdisciplinary Res Fluids, Beijing 100190, Peoples R China 2.Hong Kong Univ Sci & Technol, Dept Math, Clear Water Bay, Hong Kong, Peoples R China 3.Hong Kong Univ Sci & Technol, Div Emerging Interdisciplinary Areas, Clear Water Bay, Hong Kong, Peoples R China 4.Univ Edinburgh, Sch Engn, Edinburgh EH9 3FB, Scotland
推荐引用方式 GB/T 7714	Shan, Baochao,Su, Wei,Gibelli, Livio,et al. Molecular kinetic modelling of non-equilibrium transport of confined van der Waals fluids[J]. JOURNAL OF FLUID MECHANICS,2023,976:36.
APA	Shan, Baochao,Su, Wei,Gibelli, Livio,&Zhang, Yonghao.(2023).Molecular kinetic modelling of non-equilibrium transport of confined van der Waals fluids.JOURNAL OF FLUID MECHANICS,976,36.
MLA	Shan, Baochao,et al."Molecular kinetic modelling of non-equilibrium transport of confined van der Waals fluids".JOURNAL OF FLUID MECHANICS 976(2023):36.