Show simple item record

dc.contributor.advisorHeidi M. Nepf.en_US
dc.contributor.authorMurphy, Endaen_US
dc.contributor.otherMassachusetts Institute of Technology. Dept. of Civil and Environmental Engineering.en_US
dc.date.accessioned2006-11-07T13:33:23Z
dc.date.available2006-11-07T13:33:23Z
dc.date.copyright2006en_US
dc.date.issued2006en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/34603
dc.descriptionThesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2006.en_US
dc.descriptionIncludes bibliographical references (p. 171-183).en_US
dc.description.abstractVegetation is ubiquitous in rivers, estuaries and wetlands, strongly influencing both water conveyance and mass transport. The plant canopy affects both mean and turbulent flow structure, and thus both advection and dispersion. Accurate prediction of the fate and transport of nutrients, microbes, dissolved oxygen and other scalars depends on our ability to quantify vegetative impacts. In this thesis, the focus is on longitudinal dispersion, which traditionally has been modeled by drawing analogy to rough boundary layers. This approach is inappropriate in many cases, as the vegetation provides a significant dead zone, which may trap scalars and augment dispersion. The dead zone process is not captured in the rough boundary model. This thesis describes a new theoretical model for longitudinal dispersion in a vegetated channel, which isolates three separate contributory processes. To evaluate the performance of the model, tracer experiments and velocity measurements were conducted in a laboratory flume. Results show that the mechanism of exchange between the free stream and the vegetated region is critical to the overall dispersion, and is primarily controlled by the canopy density.en_US
dc.description.abstract(cont.) A numerical random walk particle-tracking model was developed to assess the uncertainty associated with the experimental data. Results suggest that the time scale required to obtain sound experimental data in tracer studies is longer than the commonly used Fickian time scale.en_US
dc.description.statementofresponsibilityby Enda Murphy.en_US
dc.format.extent183 p.en_US
dc.format.extent7722744 bytes
dc.format.extent7730436 bytes
dc.format.mimetypeapplication/pdf
dc.format.mimetypeapplication/pdf
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582
dc.subjectCivil and Environmental Engineering.en_US
dc.titleLongitudinal dispersion in vegetated flowen_US
dc.typeThesisen_US
dc.description.degreeS.M.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Civil and Environmental Engineering
dc.identifier.oclc71292769en_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record