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dc.contributor.authorChristopher, Michael Donalden_US
dc.date.accessioned2014-03-14T20:37:30Z
dc.date.available2014-03-14T20:37:30Z
dc.date.issued2006-05-05en_US
dc.identifier.otheretd-05182006-173437en_US
dc.identifier.urihttp://hdl.handle.net/10919/32955
dc.description.abstractSodium alanate, or the Na-Al-H system, has been the focus of intense research over the past decade due to its ability to hold almost 5 wt% of hydrogen. In this research, the effective thermal conductivity, k, of a sample of titanium-doped sodium alanate is studied over a range of operating conditions pertinent to practical on-board hydrogen storage. A transient technique employing a platinum hot-wire is used to make the measurements. A cylindrical experimental apparatus was designed with the aide of a finite element model that was used to quantify the cylinder boundary effects. The apparatus dimensions were optimized based on the finite element results with the goal of minimizing measurement uncertainty and temperature rise during testing. Finite element results were also used to predict test times and current requirements. A sample of sodium alanate was obtained and loaded into the experimental apparatus which was enclosed in a pressure vessel with a controlled atmosphere. Effective thermal conductivity was measured as a function of pressure at the fully-hydrided and fully-dehydrided states. The results from the pressure-dependence investigation were compared to an existing study that utilized an alternate measurement technique. The results matched well qualitatively â the effective thermal conductivity was highly dependent on pressure, and was found to be significantly higher in the fully-dehydrided state. However, the results of this study were 20 to 30% lower than the existing available data. Additionally, an exploratory investigation used the PCI technique to study the effect of varying composition between the fully-hydrided state and the intermediate decomposition step at a relatively constant pressure. Effective thermal conductivity did not vary significantly over this range of compositions.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartmchristo_permissions.pdfen_US
dc.relation.haspartmchristo_08-16-06.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.subjecteffective thermal conductivityen_US
dc.subjecthot-wireen_US
dc.subjectsodium alanateen_US
dc.subjecthydrogen storageen_US
dc.subjectfuel cellsen_US
dc.titleApplication of the Transient Hot-Wire Technique for Measurement of Effective Thermal Conductivity of Catalyzed Sodium Alanate for Hydrogen Storageen_US
dc.typeThesisen_US
dc.contributor.departmentMechanical Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineMechanical Engineeringen_US
dc.contributor.committeechairEllis, Michael W.en_US
dc.contributor.committeememberNelson, Douglas J.en_US
dc.contributor.committeemembervon Spakovsky, Michael R.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-05182006-173437/en_US
dc.date.sdate2006-05-18en_US
dc.date.rdate2006-08-24
dc.date.adate2006-08-24en_US


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