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dc.contributor.advisorChen, Danielen_US
dc.contributor.advisorZhang, Wenjunen_US
dc.creatorZhang, Zhimingen_US
dc.date.accessioned2010-09-03T16:54:42Zen_US
dc.date.accessioned2013-01-04T04:56:31Z
dc.date.available2011-09-16T08:00:00Zen_US
dc.date.available2013-01-04T04:56:31Z
dc.date.created2010-07en_US
dc.date.issued2010-07en_US
dc.date.submittedJuly 2010en_US
dc.identifier.urihttp://hdl.handle.net/10388/etd-09032010-165442en_US
dc.description.abstractTraditional tribology is based on the surface with random micro structures due to limitations of manufacturing technology. The modern manufacturing technology now promises to fabricate surfaces with regular micro structures (or asperities). The word ‘asperity’ refers to a single physical entity on the surface of a material, contributing to a concept called roughness in traditional tribology. Regular asperity surfaces imply that all asperities on the surface of a material have the same shape and size, and a deterministic distribution over the surface. The emergence of regular asperity surfaces will have a transformative impact to the discipline of tribology. The overall objective of this thesis is to study how the regular asperity would affect the tribological behavior. Specifically, this thesis develops a computational model to demonstrate and characterize the effect of the surface with regular anisotropic asperities (RAA) on the directional friction behavior when the surface is in a fully lubricated state. By directional friction, it is meant that friction force changes its magnitude with the change of the relative motion direction. By anisotropic asperity, it is meant that the geometry of the asperity is not symmetrical along the motion direction. This thesis presents a detailed development of the computational model by employing computational fluid dynamics (CFD) techniques. In particular, the model takes the Navier-Stokes (NS) equation as a governing equation and the Half-Sommerfeld Condition (HSC) to represent fluid behavior in the cavitation region; as such the model is named NS-HSC for short. Verification of the NS-HSC model is conducted with the information available in literature. A theory is proposed to explain the relationship between directional friction behavior and specific RAA structures. The thesis concludes: (1) the NS-HSC model is more accurate than the existing model in the literature and can be used to predict directional friction behavior and to design RAA surfaces, and (2) the proposed theory is excellent consistent with the NS-HSC model and thus useful to analysis and design of RAA surfaces for directional friction. The major contributions of this thesis are: (1) the first model in the field of tribology to predict the directional friction behavior for RAA surfaces under a fully lubricated status, (2) the first investigation, in the field of CFD, into combining the NS and HSC for modeling a laminar flow with cavitation, and (3) the first theory in the field of tribology for directional friction on fully lubricated RAA surfaces.en_US
dc.language.isoen_USen_US
dc.subjectRegular anisotropic asperityen_US
dc.subjectDirectional frictionen_US
dc.subjectFilm ruptureen_US
dc.titleModeling and understanding of directional friction on a fully lubricated surface with regular anisotropic asperitiesen_US
thesis.degree.departmentMechanical Engineeringen_US
thesis.degree.disciplineMechanical Engineeringen_US
thesis.degree.grantorUniversity of Saskatchewanen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMaster of Science (M.Sc.)en_US
dc.type.materialtexten_US
dc.type.genreThesisen_US
dc.contributor.committeeMemberBoulfiza, Mohameden_US
dc.contributor.committeeMemberBurton, Richard T.en_US
dc.contributor.committeeMemberBergstrom, Donald J.en_US


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