Boundary element simulation of three-dimensional saltwater intrusion problems.

Persistent Link:
http://hdl.handle.net/10150/186100
Title:
Boundary element simulation of three-dimensional saltwater intrusion problems.
Author:
Srivastava, Rajesh.
Issue Date:
1992
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
A numerical model for the analysis of three-dimensional flow of two immiscible fluids through porous media is developed based on the boundary integral equation technique. Hydrodynamic dispersion is assumed to be negligible and therefore a sharp interface is assumed to separate the two fluids. Triangular elements are used to discretize the boundary of the solution domain and the areal integration over triangles is reduced to a linear form by carrying out analytical integration along one coordinate direction. As a result,the singular integrals are reduced to completely analytic forms, thus avoiding the need of using a large number of Gauss points for numerical integration as used in some earlier models. This is found to result in substantial saving in computer time and increased accuracy of results, even at points close to the boundary. The model is verified by comparing its results to those from analytic solutions and other numerical methods like the Finite Element Method. An efficient two-dimensional Finite Element Model is also developed to simulate salt water intrusion. Both the Boundary Element Model and the Finite Element Model are applied to the problem of sea water intrusion in the coastal aquifer of Guam and the results are discussed. It is observed that the boundary element method, in general, requires smaller time steps as compared to the finite element method in order to get stable results for transient flow problems. The increase in number of time steps, however, is compensated by the smaller number of nodes and the overall computational effort appears to be of the same order for both the methods.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Dissertations, Academic.; Civil engineering.; Hydrology.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Civil Engineering and Engineering Mechanics; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Contractor, Dinshaw N.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleBoundary element simulation of three-dimensional saltwater intrusion problems.en_US
dc.creatorSrivastava, Rajesh.en_US
dc.contributor.authorSrivastava, Rajesh.en_US
dc.date.issued1992en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractA numerical model for the analysis of three-dimensional flow of two immiscible fluids through porous media is developed based on the boundary integral equation technique. Hydrodynamic dispersion is assumed to be negligible and therefore a sharp interface is assumed to separate the two fluids. Triangular elements are used to discretize the boundary of the solution domain and the areal integration over triangles is reduced to a linear form by carrying out analytical integration along one coordinate direction. As a result,the singular integrals are reduced to completely analytic forms, thus avoiding the need of using a large number of Gauss points for numerical integration as used in some earlier models. This is found to result in substantial saving in computer time and increased accuracy of results, even at points close to the boundary. The model is verified by comparing its results to those from analytic solutions and other numerical methods like the Finite Element Method. An efficient two-dimensional Finite Element Model is also developed to simulate salt water intrusion. Both the Boundary Element Model and the Finite Element Model are applied to the problem of sea water intrusion in the coastal aquifer of Guam and the results are discussed. It is observed that the boundary element method, in general, requires smaller time steps as compared to the finite element method in order to get stable results for transient flow problems. The increase in number of time steps, however, is compensated by the smaller number of nodes and the overall computational effort appears to be of the same order for both the methods.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectDissertations, Academic.en_US
dc.subjectCivil engineering.en_US
dc.subjectHydrology.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineCivil Engineering and Engineering Mechanicsen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairContractor, Dinshaw N.en_US
dc.contributor.committeememberSorooshian, Sorooshen_US
dc.contributor.committeememberHaldar, Achintyaen_US
dc.contributor.committeememberChandra, Abhijiten_US
dc.identifier.proquest9310609en_US
dc.identifier.oclc714180080en_US
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