Research Abstracts Online
2008 - March 2009
University of Minnesota Twin Cities
Institute of Technology
Department of Civil Engineering
St. Anthony Falls Laboratory
PI: Heinz G. Stefan, Associate Fellow
Simulations and Analysis of Physical, Chemical, and Biological Processes Affecting Water Quality in Freshwater Systems
These researchers have developed deterministic, unsteady, year-round lake and stream water quality/ecosystem simulation models and are expanding, validating, and applying them. These models simulate a multitude of physical, chemical and biological processes and give, for example, water temperature, dissolved oxygen, primary productivity and fish habitat distributions in water systems. Simulations can be made for continuous long-term periods (e.g. 30 years), or for periods of a few days on individual water bodies with high temporal resolution. The researchers are using MSI resources for three projects in this broad area.
Simulations of atmospheric flows over surface topography and vegetation have numerous applications, but the primary goal of the first project is to better describe the atmospheric interactions with sheltered water bodies such as small lakes and sheltered bays. Dynamic sub-filter-scale closure models for large-eddy simulations are important underpinnings of the understanding of flows, atmospheric and otherwise, over roughness and topographic transitions.
A second, continuing project is the study of flow and mass transfer processes at a sediment/water interface such as found in streams and rivers, in lakes and in estuaries. Slow water motions near the sediment/water interface can have a limiting effect on mass transfer and biological activity inside the sediments. This research involves flow and mass transfer simulations to investigate penetrative dispersion and uptake/release of solutes in various sedimentary matrices.
A third project is the development of an integrated deterministic hydro-thermal simulation model for water temperatures in surface runoff and shallow groundwater recharge from watersheds under various stages of land (urban) development. This project requires the integration of hydrologic processes with heat transfer processes in many different environmental settings. It also includes the study of the effects of man-made systems, including residential and commercial areas, on heat transfer in the aquatic environment. The application of this research is for coldwater (trout) streams that become adversely affected by urban development.
Filiz Dadasser-Celik, Graduate Student
Timothy Erickson, Graduate Student
William Herb, Research Associate
Ben Janke, Graduate Student
Corey Markfort, Graduate Student
Eric Novotny, Graduate Student
Qin Qian, Department of Civil Engineering, Lamar University, Beaumont, Texas
Craig Taylor, Graduate Student