An evaluation of the thermal characteristics of a flat plate heat pipe spreader /
An evaluation of the thermal characteristics of a flat plate heat pipe spreader was performed through an analytical, numerical, and experimental analysis. The physical system considered was comprised of a high heat flux heat source attached to the center of a flat plate heat pipe, mounted at the ba...
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| Format: | Thesis eBook |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
2000.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Summary: | An evaluation of the thermal characteristics of a flat plate heat pipe spreader was performed through an analytical, numerical, and experimental analysis. The physical system considered was comprised of a high heat flux heat source attached to the center of a flat plate heat pipe, mounted at the base of a plate-finned heat sink and cooled by forced convection. In the analysis, the theoretical maximum operating conditions for the heat pipe are predicted, and it is found that the specific heat pipe configuration would most likely fail based on capillary limitations of the wick structure for conditions typical of electronic cooling applications. The mass and heat transfer processes which contribute to the capillary limitation were considered in theory, and a novel technique which utilizes well-known conventional heat pipe relations for pressure loss was developed to estimate the point of heat pipe failure. In addition, a thermal resistance network was developed in an effort to predict the temperature drop across the heat pipe spreader. Through a separate approach, a numerical model was developed to solve the conjugate problem of heat transfer in the heat pipe/heat sink with turbulent forced convection. In this approach, the heat pipe was modeled as a solid material having a high effective conductivity. Finally, the system was tested experimentally, and the results were compared to the analytical and numerical results. It was found that the capillary limit model over-predicted the measured point of heat pipe failure by several orders of magnitude, and the resistance model under-represented the actual resistance by a factor of 2 to 3. In addition, a change in thermal resistance with power input was discovered during experimentation that was not predicted by the analysis. The numerical model was compared to the experimental results and a relation for the effective conductivity as a function of power input was determined. Complexities associated with the internal heat and mass transfer processes of the flat plate heat pipe spreader were thoroughly discussed and the discrepancies between the experimental and analytical results were examined. |
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| Item Description: | "Major subject: Mechanical Engineering". Vita. |
| Physical Description: | xvi, 147 leaves : illustrations ; 28 cm. Also available online. Issued also on microfiche from Lange Micrographics. |
| Bibliography: | Includes bibliographical references (leaves 99-101). |