臺灣博碩士論文加值系統

本論文探討垂直圓柱體在多孔介質中混合對流熱質能傳輸之研究。依據Adrian Bejan、Khairy R.Khair、F. C. Lai、F. A. Kulacki與Jin-Yuan Liu的多孔介質中流場模式，以及體平均理論、邊界層理論與波氏近似法的運用，再以局部非相似解的數值方法，分析不同的流域、浮力效應、擴散效應、曲率和自然對流作用，對多孔介質流場之速度場、溫度場與濃度場的影響。
所得結果與相關文獻的結論做比較，均可獲得一致性的趨勢。另外所得出對流比Ω對流場傳輸機制的影響，在相關文獻中鮮少看到討論於此，當考慮自然對流與強制對流同時作用時，本論文的結果可彌補文獻中之不足。
最後，再以修正之達西定律推導完整的流場動量方程式，探討因達西定律所造成流場不符合物理現象的原因，得出流場完整之速度場分佈情形。

This thesis concerns the problem of combined heat and mass mixed convection heat transfer from a vertical cylinder embedded in a porous medium. The study is based upon the theorem developed by Adrian Bejan and Khairy R. Khair, F. C. Lai and F. A. Kulacki, Jin-Yuan Liu. By appling the volume averaging technicques, boundary layer theorem, Boussinesq approximation, and local non-similarity method, the effects of different domain, buoyancy ration, diffusivity ratio, curvature and convection ratio are examined and analyzed.
Comparisons of the present results with the related references have found the similar trend. On the other hand, little references discuss about the influence of the mixed convection ratio on the transfer mechanism; the results of this thesis provide a supplement to the literature.
Finally, a modified model on fluid flow in porous media is proposed for further development. The model is capable of describing the viscous and inertial effects. Some preliminary results of the flow field are presented and briefly discussed.