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dc.contributor.authorSklar, Akiva A.en_US
dc.date.accessioned2007-03-27T18:16:47Z
dc.date.available2007-03-27T18:16:47Z
dc.date.issued2005-11-17en_US
dc.identifier.urihttp://hdl.handle.net/1853/14020
dc.description.abstractThe performance of a novel micro-thermodielectric power generation device (MTDPG) was investigated in order to determine if thermodielectric power generation can compete with current portable power generation technologies. Thermodielectric power generation is a direct energy conversion technology that converts heat directly into high voltage direct current. It requires dielectric (i.e., capacitive) materials whose charge storing capabilities are a function of temperature. This property is exploited by heating these materials after they are charged; as their temperature increases, their charge storage capability decreases, forcing them to eject a portion of their surface charge to an appropriate electronic storage device. Previously, predicting the performance of a thermodielectric power generator was hindered by a poor understanding of the materials thermodynamic properties and the affect unsteady heat transfer losses have on system performance. In order to improve predictive capabilities in this study, a thermodielectric equation of state was developed that describes the relationship between the applied electric field, the surface charge stored by the thermodielectric material, and its temperature. This state equation was then used to derive expressions for the material's thermodynamic states (internal energy, entropy), which were subsequently used to determine the optimum material properties for power generation. Next, a numerical simulation code was developed to determine the heat transfer capabilities of a micro-scale parallel plate heat recuperator (MPPHR), a device designed specifically to a) provide the unsteady heating and cooling necessary for thermodielectric power generation and b) minimize the unsteady heat transfer losses of the system. The previously derived thermodynamic equations were then incorporated into the numerical simulation code, creating a tool capable of determining the thermodynamic performance of an MTDPG, in terms of the thermal efficiency, percent Carnot efficiency, and energy/power density, when the material properties and the operating regime of the MPPHR were varied. The performance of the MTDPG was optimized for an operating temperature range of 300 500 K. The optimization predicted that the MTDPG could provide a thermal efficiency of 29.7 percent. This corresponds to 74.2 percent of the Carnot efficiency. The power density of this MTDPG depends on the operating frequency and can exceed 1,000,000 W/m3.en_US
dc.format.extent2711247 bytes
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.publisherGeorgia Institute of Technologyen_US
dc.subjectThermodielectric power generation pyroelectricen_US
dc.subject.lcshThermoelectric generatorsen_US
dc.subject.lcshThermodynamicsen_US
dc.subject.lcshPyroelectricityen_US
dc.subject.lcshHeat engineeringen_US
dc.subject.lcshElectric power distribution Direct currenten_US
dc.titleA Numerical Investigation of a Thermodielectric Power Generation Systemen_US
dc.typeDissertationen_US
dc.description.degreePh.D.en_US
dc.contributor.departmentAerospace Engineeringen_US
dc.description.advisorCommittee Chair: Dr. Ben Zinn; Committee Member: Dr. Jeff Jagoda; Committee Member: Dr. Lakshmi Sankar; Committee Member: Dr. S. Mostafa Ghiaasiaan; Committee Member: Dr. Yedidia Neumeieren_US


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