干旱区生态环境知识资源中心(Arid): Users` manual for LEHGC: A Lagrangian-Eulerian Finite-Element Model of Hydrogeochemical Transport Through Saturated-Unsaturated Media. Version 1.1

Arid

DOI	10.2172/174680
报告编号	SAND--95-1121
来源ID	OSTI_ID: 174680
	Users` manual for LEHGC: A Lagrangian-Eulerian Finite-Element Model of Hydrogeochemical Transport Through Saturated-Unsaturated Media. Version 1.1
	Yeh, Gour-Tsyh [Pennsylvania State Univ., University Park, PA (United States). Dept. of Civil and Environmental Engineering]; Carpenter, S.L. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Earth and Planetary Sciences]; Hopkins, P.L.; Siegel, M.D. [Sandia National Labs., Albuquerque, NM (United States)]
英文摘要	The computer program LEHGC is a Hybrid Lagrangian-Eulerian Finite-Element Model of HydroGeo-Chemical (LEHGC) Transport Through Saturated-Unsaturated Media. LEHGC iteratively solves two-dimensional transport and geochemical equilibrium equations and is a descendant of HYDROGEOCHEM, a strictly Eulerian finite-element reactive transport code. The hybrid Lagrangian-Eulerian scheme improves on the Eulerian scheme by allowing larger time steps to be used in the advection-dominant transport calculations. This causes less numerical dispersion and alleviates the problem of calculated negative concentrations at sharp concentration fronts. The code also is more computationally efficient than the strictly Eulerian version. LEHGC is designed for generic application to reactive transport problems associated with contaminant transport in subsurface media. Input to the program includes the geometry of the system, the spatial distribution of finite elements and nodes, the properties of the media, the potential chemical reactions, and the initial and boundary conditions. Output includes the spatial distribution of chemical element concentrations as a function of time and space and the chemical speciation at user-specified nodes. LEHGC Version 1.1 is a modification of LEHGC Version 1.0. The modification includes: (1) devising a tracking algorithm with the computational effort proportional to N where N is the number of computational grid nodes rather than N{sup 2} as in LEHGC Version 1.0, (2) including multiple adsorbing sites and multiple ion-exchange sites, (3) using four preconditioned conjugate gradient methods for the solution of matrix equations, and (4) providing a model for some features of solute transport by colloids.
出版年	1995
报告类型	Technical Report
语种	英语
国家	美国
来源学科分类	54 ENVIRONMENTAL SCIENCES ; 05 NUCLEAR FUELS ; RADIONUCLIDE MIGRATION ; L CODES ; FLOW MODELS ; TWO-DIMENSIONAL CALCULATIONS ; RADIOECOLOGICAL CONCENTRATION ; SOILS ; GROUND WATER ; RADIOACTIVE WASTES
URL	http://www.osti.gov/scitech/servlets/purl/174680
资源类型	科技报告
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/266396
推荐引用方式 GB/T 7714	Yeh, Gour-Tsyh [Pennsylvania State Univ., University Park, PA ,Carpenter, S.L. [Univ. of New Mexico, Albuquerque, NM ,Hopkins, P.L.,et al. Users` manual for LEHGC: A Lagrangian-Eulerian Finite-Element Model of Hydrogeochemical Transport Through Saturated-Unsaturated Media. Version 1.1,1995.