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dc.contributor.authorVilla, Margarita Mariaen_US
dc.date.accessioned2014-03-14T20:35:32Z
dc.date.available2014-03-14T20:35:32Z
dc.date.issued2009-05-01en_US
dc.identifier.otheretd-05072009-130136en_US
dc.identifier.urihttp://hdl.handle.net/10919/32333
dc.description.abstractImproving the quality factor of the mechanical oscillations of micron scale beams in a viscous fluid, such as water, is an open challenge of direct relevance to the development of future technologies. We study the stochastic dynamics of doubly-clamped micron scale beams in a viscous fluid driven by Brownian motion. We use a thermodynamic approach to compute the equilibrium fluctuations in beam displacement that requires only deterministic calculations. From calculations of the autocorrelations and noise spectra we quantify the beam dynamics by the quality factor and resonant frequency of the fundamental flexural mode over a range of experimentally accessible geometries. We carefully study the effects of the grid resolution, domain size, linear response, and time-step for the numerical simulations. We consider beams with uniform rectangular cross-section and explore the increased quality factor and resonant frequency as a baseline geometry is varied by increasing the width, increasing the thickness, and decreasing the length. The quality factor is nearly doubled by tripling either the width or the height of the beam. Much larger improvements are found by decreasing the beam length, however this is limited by the appearance of additional modes of dissipation. Overall, the stochastic dynamics of the wider and thicker beams are well predicted by a two-dimensional approximate theory beyond what may be expected based upon the underlying assumptions, whereas the shorter beams require a more detailed analysis.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartMVilla_MS_Thesis.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectmicrofuidicsen_US
dc.subjectquality factoren_US
dc.subjectBrownianen_US
dc.subjectdoubly-clamped beamsen_US
dc.titleTailoring the Geometry of Micron Scale Resonators to Overcome Viscous Dampingen_US
dc.typeThesisen_US
dc.contributor.departmentMechanical Engineeringen_US
thesis.degree.nameMaster of Engineeringen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
dc.contributor.committeechairPaul, Mark R.en_US
dc.contributor.committeememberInman, Daniel J.en_US
dc.contributor.committeememberBehkam, Baharehen_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-05072009-130136/en_US
dc.date.sdate2009-05-07en_US
dc.date.rdate2009-05-22
dc.date.adate2009-05-22en_US


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