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Chunmiao Zheng

Publications and source records attributed to Chunmiao Zheng.

22 records · Page 2Linked to original sources
USGS2006

Progress made in groundwater flow and transport modeling

A special session, “Automated Parameter Identification and Sensitivity Analysis in Groundwater Flow and Transport,” was held at the Spring AGU meeting last May to explore recent scientific and technological developments in this expanding research area. The problems and approaches discussed are crucial to any field of Earth science in which models are used to represent physical processes and simulated values are compared with measured quantities. Although methods for automated parameter identification and sensitivity analysis were first developed at about the same time as numerical groundwater models, they are rarely used. Presentations at this special session clearly demonstrated the potential contributions of these methods for more insightful groundwater model development and calibration.

Eos, Transactions, American Geophysical Union↗
USGS2005

SVFlux and ChemFlux: Software for two-dimensional/three-dimensional finite element variably saturated flow and transport modeling

SVFlux and ChemFlux are a pair of finite element models designed to simulate the movement of water and contaminants in two and three dimensions under variably saturated conditions. The transport simulator ChemFlux is designed as a companion to the flow simulator SVFlux. SVFlux and ChemFlux are commercial products developed by SoilVision Systems Ltd. and can be purchased via the company's Web site. SVFlux and ChemFlux run under Microsoft Windows NT/2000/XP operating systems, and require a minimum of 128 MB RAM and approximately 150 MB hard drive space. The software includes Windows-based graphical user interface, numerical model engines, and post-processing programs. SVFlux and ChemFlux are suitable for numerous applications such as modeling of water and transport modeling in aquifers and the unsaturated zone, modeling of seepage across dams and geomembranes, and modeling of infiltration, excess pore water buildup, and dissipation. This article is based on two independent reviews of SVFlux (versions 4.05 and 5.04) and ChemFlux (versions 3.00 and 3.03).

Groundwater↗
USGS2001

MODFLOW-2000, the U.S. Geological Survey modular ground-water model: User guide to the LMT6 package, the linkage with MT3DMS for multi-species mass transport modeling

MODFLOW-2000, the newest version of MODFLOW, is a computer program that numerically solves the three-dimensional ground-water flow equation for a porous medium using a finite-difference method. MT3DMS, the successor to MT3D, is a computer program for modeling multi-species solute transport in three-dimensional ground-water systems using multiple solution techniques, including the finite-difference method, the method of characteristics (MOC), and the total-variation-diminishing (TVD) method. This report documents a new version of the Link-MT3DMS Package, which enables MODFLOW-2000 to produce the information needed by MT3DMS, and also discusses new visualization software for MT3DMS. Unlike the Link-MT3D Packages that coordinated previous versions of MODFLOW and MT3D, the new Link-MT3DMS Package requires an input file that, among other things, provides enhanced support for additional MODFLOW sink/source packages and allows list-directed (free) format for the flow model produced flow-transport link file. The report contains four parts: (a) documentation of the Link-MT3DMS Package Version 6 for MODFLOW-2000; (b) discussion of several issues related to simulation setup and input data preparation for running MT3DMS with MODFLOW-2000; (c) description of two test example problems, with comparison to results obtained using another MODFLOW-based transport program; and (d) overview of post-simulation visualization and animation using the U.S. Geological Survey?s Model Viewer.

Open-File Report↗