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dc.contributor.advisorMichael S Triantafyllou.en_US
dc.contributor.authorSchulmeister, James Crandallen_US
dc.contributor.otherMassachusetts Institute of Technology. Dept. of Mechanical Engineering.en_US
dc.date.accessioned2013-03-28T18:13:44Z
dc.date.available2013-03-28T18:13:44Z
dc.date.copyright2012en_US
dc.date.issued2012en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/78196
dc.descriptionThesis (S.M. in Ocean Engineering)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.en_US
dc.descriptionCataloged from PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references (p. 61-62).en_US
dc.description.abstractThe hydrodynamic forces on ocean vehicles increase dramatically during sharp maneuvers as compared to forward motion due to large areas of separated flow. These large forces severely limit maneuverability and reduce efficiency. Applying active flow separation control to ocean vehicles would reduce resistance during maneuvers and thereby improve maneuvering performance. In this thesis I discuss experiments in active separation control in a simpler, but still relevant, two-dimensional flow past a circular cylinder at moderate sub-critical Reynolds numbers (37,000 and 52,000 in experiment and 100 and 10,000 in simulation). The active control injects momentum into the boundary layer via the moving surfaces of two small control cylinders located near boundary layer separation and rotated by servo motors. The relationship between drag and rotation rate is found to be Reynolds number regime dependent; at Re = 100 the drag decreases linearly with rotation rate and at Re = 10,000, the relationship is non-linear. This nonlinearity appears to be due to the interaction between vortex shedding from the small control cylinders (which does not occur at Re = 100) and the main cylinder wake. Computational two-dimensional viscous simulations are consistent with the physical experiment and help to illustrate the phenomenon. Finally, the power consumed by the active control mechanism is considered and estimated to be significantly smaller than the power savings in reduced drag.en_US
dc.description.statementofresponsibilityby .James Crandall Schulmeisteren_US
dc.format.extent62 p.en_US
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/1721.1/7582en_US
dc.subjectMechanical Engineering.en_US
dc.titleFlow separation control with rotating cylindersen_US
dc.typeThesisen_US
dc.description.degreeS.M.in Ocean Engineeringen_US
dc.contributor.departmentMassachusetts Institute of Technology. Dept. of Mechanical Engineering.en_US
dc.identifier.oclc830377441en_US


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