Thesis
A numerical study of near-field dispersion within and above a forest canopy
Washington State University
Master of Science (MS), Washington State University
2005
Handle:
https://hdl.handle.net/2376/359
Abstract
The motivation for this project was to develop a tool to guide forest managers in protecting high value forest stands from bark beetle infestations. Several field experiments have been conducted in multiple forest canopies linking tracer gas concentration fields with meteorological and canopy parameters. Field experiments are often limited by cost, locations, and meteorological conditions. Numerical simulations are far less expensive and allow for many variations in flow parameters such as atmospheric stability, wind speed and direction. Near-field pheromone dispersion within and above a southern loblolly pine canopy with neutral and unstable atmospheric conditions was investigated using large eddy simulation (LES). LES captures coherent structures within and above the canopy which are responsible for the majority of scalar transport into and out of forest canopies. LES resolves large energy containing eddies while modeling smaller dissipative eddies using a sub grid scale model. The model incorporates canopy effects based on leaf area index (LAI), leaf area density (LAD), and stem density. Convective conditions are also modeled using a heat source term based on above canopy heat flux. Results of the LES are compared with experimental data from a recent tracer gas field study. The LES solution predicts higher mean velocity and concentration within the canopy, but demonstrates similar instantaneous trends for velocity and concentration.
Metrics
4 File views/ downloads
21 Record Views
Details
- Title
- A numerical study of near-field dispersion within and above a forest canopy
- Creators
- Steven Lee Edburg
- Contributors
- David E Stock (Committee Member) - Washington State University, Mechanical and Materials Engineering, School ofBrian K Lamb (Committee Member) - Washington State University, Civil and Environmental Engineering, Department ofPRASHANTA DUTTA (Committee Member) - Washington State University, Mechanical and Materials Engineering, School of
- Awarding Institution
- Washington State University
- Academic Unit
- Mechanical and Materials Engineering, School of
- Theses and Dissertations
- Master of Science (MS), Washington State University
- Publisher
- Washington State University; [Pullman, Washington] :
- Identifiers
- 99900525002801842
- Language
- English
- Resource Type
- Thesis