Parallel Least-Squares Finite Element Method for Large Eddy Simulation of Large Scale Environmental Flows and Transport Processes

EPA Grant Number: R825200
Title: Parallel Least-Squares Finite Element Method for Large Eddy Simulation of Large Scale Environmental Flows and Transport Processes
Investigators: Tsang, Tate H. , Bai, Zhaojun , Yost, Scott A.
Institution: University of Kentucky
EPA Project Officer: Saint, Chris
Project Period: November 1, 1996 through October 31, 1999 (Extended to November 14, 2000)
Project Amount: $475,670
RFA: High Performance Computing (1996) RFA Text |  Recipients Lists
Research Category: Health , Ecosystems , Environmental Statistics

Description:

Numerical modeling is one of the indispensable tools to analyze complicated and challenging environmental problems. The success of numerical modeling depends on the formulation of a reliable turbulence model and the development of a robust and efficient numerical method which can simulate large scale problems with minimum use of computer memory. In this work, the Large Eddy Simulation (LES) technique and the Least-Squares Finite Element Method (LSFEM) are combined to simulate large scale environmental flows and transport processes. Two types of challenging, computationally intense problems crucial to our environment will be tackled: 1) time-dependent, three dimensional turbulent flow and dispersion of hazardous/toxic air pollutants around buildings and industrial complex; and 2) time-dependent, three dimensional turbulent flow and dispersion of contaminants in Green Bay.

A robust and efficient matrix-free least-Squares finite element method has been used to simulate moderately large scale three dimensional fluid flows and transport processes. For example, 1.1 million unknown flow variables at 270,000 nodes have been found by the LSFEM. Parallel LSFEM has also been developed for convective transport of 11 reactive species with more than 1.9 million unknowns on 173,225 nodes. Linear speedup has been achieved for this simulation on a Convex Exemplar parallel computer. In addition, the memory requirement for the matrix-free LSFEM is at least 20 to 30 times less than other methods.

The goal of this research is to extend and modify our LSFEM/LES codes and to develop highly parallelizable algorithms to simulate flows and transport processes in domains with 1 to 10 million nodes. The results of this research should find numerous applications to large scale simulation of environmental flows and transport processes in domains with complex geometry.

Publications and Presentations:

Publications have been submitted on this project: View all 16 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 8 journal articles for this project

Supplemental Keywords:

supercomuting, modeling, parallel algorithms,transport, flow, finite element, least squares, Green Bay., RFA, Scientific Discipline, Geographic Area, Ecosystem Protection/Environmental Exposure & Risk, State, computing technology, Environmental Monitoring, Ecology and Ecosystems, air quality modeling, ecosystem modeling, fate and transport, large eddy simulation, least squares, finite element method, HPCC, three dimensional turbulant flow, computer science, numerical model, data analysis, information technology, parallel computing, convective transport

Relevant Websites:

http://www.engr.uky.edu/cme/faculty/tsangExit EPA icon

Progress and Final Reports:

1998 Progress Report
1999 Progress Report