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dc.contributor.advisorKöymen, Hayrettinen_US
dc.contributor.authorOğuz, Hüseyin Kağanen_US
dc.date.accessioned2016-01-08T18:10:44Z
dc.date.available2016-01-08T18:10:44Z
dc.date.issued2009
dc.identifier.urihttp://hdl.handle.net/11693/14904
dc.descriptionAnkara : The Department of Electrical and Electronics Engineering and the Institute of Engineering and Sciences of Bilkent University, 2009.en_US
dc.descriptionThesis (Master's) -- Bilkent University, 2009.en_US
dc.descriptionIncludes bibliographical references leaves 52-55.en_US
dc.description.abstractFinite element method (FEM) is used for transient dynamic analysis of capacitive micromachined ultrasonic transducers (CMUT), which is particularly useful when the membranes are driven in the nonlinear regime. A transient FEM analysis shows that CMUT exhibits strong nonlinear behavior even at very low AC excitation under DC bias. One major disadvantage of FEM is the excessive time required for simulation. Harmonic Balance (HB) analysis, on the other hand, provides an accurate estimate of the steady-state response of nonlinear circuits very quickly. It is common to use Mason’s equivalent circuit to model the mechanical section of CMUT. However, it is not appropriate to terminate Mason’s mechanical LC section by a rigid piston’s radiation impedance, especially, for an immersed CMUT. We studied the membrane behavior using a transient FEM analysis and found out that for a wide range of harmonics around the series resonance, the membrane displacement can be modeled as a clamped radiator. We considered the root mean square of the velocity distribution on the membrane surface as the circuit variable rather than the average velocity. With this definition the kinetic energy of the membrane mass is the same as that in the model. We derived the force and current equations for a clamped radiator and implemented them in a commercial HB simulator. We observed much better agreement between FEM and the proposed equivalent model, compared to the conventional model.en_US
dc.description.statementofresponsibilityOğuz, Hüseyin Kağanen_US
dc.format.extentxiii, 55 leaves, graphicsen_US
dc.language.isoEnglishen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectCMUTen_US
dc.subjecttransient analysisen_US
dc.subjectharmonic balanceen_US
dc.subjectequivalent circuiten_US
dc.subjectnonlinear modelingen_US
dc.subject.lccTK5982 .O48 2009en_US
dc.subject.lcshUltrasonic transducers.en_US
dc.titleNonlinear modelling of an immersed transmitting capacitive micromachined ultrasonic transducer for harmonic balance analysisen_US
dc.typeThesisen_US
dc.departmentDepartment of Electrical and Electronics Engineeringen_US
dc.publisherBilkent Universityen_US
dc.description.degreeM.S.en_US


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