碩士 / 國防大學中正理工學院 / 兵器系統工程研究所 / 90 / The present study aims on the thermal-flow problems of different kinds of extrusion heat sink. Both the CFD technique and in-direct IR thermographer are employing to evaluate the flow structure and surface temperature. The computational model is established on the consideration of conjugate heat transfer. An oil flow visualization method is used to capture the major flow characteristics. In CFD, the approach of analysis first generates solid model and computational grids by ICEM/CFD package; then a 3D commercially available finite-volume software CFX4.4 has been used to solve the governing equations. At last, the Fieldview and Tecplot packages are used to visualize the detailed flow phenomena and to analysis quantitatively. The study focus on temperature, velocity and pressure distribution in different Reynolds number and H/CH ratio. In experiment, IR imaging method provides visibility of full field temperature and smoke wire entrainment techniques provides perfect visualization of flow pattern .
The simulational results show in good agreement with experimental data. The flow structure for heat sink L and S are quite different especially in the passage of neighboring fins. Another finding was that heat sink L had lower surface temperature than that of heat sink S when Reynolds number was kept at 550. Last, the performance of heat sink L (H/CH=0.67) shows better heat dissipation effect than that of heat sink S (H/CH=0.25). This is due to the pressure drop for heat sink S is larger than that of heat sink L. The bypass effect results in strong influence on the heat transfer performance of heat sink.
| Identifer | oai:union.ndltd.org:TW/090CCIT0157021 |
| Date | January 2002 |
| Creators | 胡中博 |
| Contributors | 苗志銘 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 95 |
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