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dc.contributor.advisorLau, Sai C.en_US
dc.contributor.advisorMarotta, Eden_US
dc.creatorLee, Sang Wonen_US
dc.date.accessioned2010-01-15T00:15:30Zen_US
dc.date.accessioned2010-01-16T02:23:31Z
dc.date.available2010-01-15T00:15:30Zen_US
dc.date.available2010-01-16T02:23:31Z
dc.date.created2007-08en_US
dc.date.issued2009-06-02en_US
dc.identifier.urihttp://hdl.handle.net/1969.1/ETD-TAMU-1940
dc.description.abstractThe heat transfer characteristics of airflows in serpentine cooling channels in stator vanes of gas turbines and the novel QuTech® Heat Pipe (QTHP) for electronic cooling applications were studied. The cooling channels are modeled as smooth and roughened two-pass trapezoidal channels with a 180° turn over a range of Reynolds numbers between about 10,000 and 60,000. The naphthalene sublimation technique and the heat and mass transfer analogy were applied. The results showed that there was a very large variation of the local heat (mass) transfer distribution in the turn and downstream of the turn. The local heat (mass) transfer was high near the end wall and the downstream outer wall in the turn and was relatively low in two regions near the upstream outer wall and the downstream edge at the tip of the divider wall in the turn. The variation of the local heat (mass) transfer was larger with ribs on two opposite walls than with smooth walls. The regional average heat (mass) transfer was lower in the turn and higher in the entire channel with the flow entering the channel through the larger straight section than when the flow was reversed. The pressure drop across the turn was higher with the flow entering the channel through the larger channel than when the flow was reversed. Thermal performance of the QuTech® Heat Pipe was identified over a range of inclination angles between 90° and -90° and thermal mechanism of the QTHP was studied with GC-MS, ICP-OES, XRD, XPS, and DSC. This study resulted in the following findings: the performance of the QTHP was severely dependent on gravity; the QTHP utilizes water as working fluid; there were inorganic components such as Na, K, P, S, and Cr, etc.; and the vaporization temperature of the working fluid (mostly water) was lower than the boiling temperature of pure water. This was due to the presence of inorganic salt hydrates in the QTHP. It may be concluded that thermal performance of heat pipes increases with additional latent heat of fusion energy and energy required to release water molecules from salt hydrates.en_US
dc.format.mediumelectronicen_US
dc.format.mimetypeapplication/pdfen_US
dc.language.isoen_USen_US
dc.subjectforce convective heat trasnferen_US
dc.subjecttwo phase heat trasnferen_US
dc.subjectgas turbine airfoilen_US
dc.subjectheat pipeen_US
dc.titleHeat transfer characteristics of a two-pass trapezoidal channel and a novel heat pipeen_US
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentMechanical Engineeringen_US
thesis.degree.disciplineMechanical Engineeringen_US
thesis.degree.grantorTexas A&M Universityen_US
thesis.degree.nameDoctor of Philosophyen_US
thesis.degree.levelDoctoralen_US
dc.contributor.committeeMemberAnand, N. K.en_US
dc.contributor.committeeMemberHan, Je C.en_US
dc.contributor.committeeMemberHassan, Yassin A.en_US
dc.type.genreElectronic Dissertationen_US
dc.type.materialtexten_US
dc.format.digitalOriginborn digitalen_US


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