本論文第一部分以理論分析多孔性介質中的液態薄膜蒸發問題，考慮液體沿著置於多孔性介質中的垂直等溫加熱板從上方流下，空氣為與淋水同方向的強制對流流場。空氣側及水膜側流場均採用二維層流邊界層模式，多孔性流場考慮包含對流效應、慣性效應及邊界效應的非達西模式(non-Darcy model)。內文清楚闡述兩流體在液體與空氣介面的溫度及濕度變化，及沿著壁面的局部熱傳、質傳分佈，進而探討空氣流速(Rea)、進口淋水量(Rel)、環境相對濕度()及顆粒直徑(dp)的影響。數值結果顯示潛熱熱傳是多孔性介質中的薄膜蒸發問題主要的熱傳機制。空氣進口流速愈高可提高液體與空氣介面的溫度和濕度梯度，進口淋水量小、顆粒直徑大及環境相對濕度低則可有效提高總熱傳量和總蒸發量。

本論文第二部份利用CFDRC計算流體力學軟體分析在其中置入一厚度具可傳導性水平隔板與填充部份多孔性材料的封閉空間，探討上下壁面不同溫差、不同隔板熱傳導係數 與放置位置、長寬比例對熱傳的影響。研究結果顯示渦漩數的多寡在一般流體中是熱傳效果的指標之ㄧ，渦漩數愈多代表對流程度愈強。此外，多孔性介質厚度愈大、長寬比例愈大，熱傳能力愈強。而隔板的熱傳導係數 愈大會顯著提升整體熱傳效應。

The first part of the present study is to analyze theoretically the non-Darcian effects and inlet conditions on the forced convection flow with liquid film evaporation in porous medium. The physical scheme considers a liquid-air streams combined system; the liquid film falls down along the plate and is exposed to a co-current forced moist air stream. The axial-momentum, energy and concentration equations for the air and water flows are developed based on the steady 2-D laminar boundary layer model. The non-Darcian convective, boundary and inertia effects are considered to describe the momentum characteristics of porous medium. The paper clearly describes the temperature and mass concentration variations at the liquid-air interface and provides the heat and mass transfer distributions along the heated plate. Furthermore, the effects of inlet air Reynolds number Rea, inlet liquid Reynolds number Rel, porous material diameter dp, and ambient relative humidity  on the heat transfer and evaporating rate are evaluated. The numerical results show that the latent heat transfer plays a dominant role on heat transfer. In addition, higher Rea and dp, lower Rel and  enhance the total heat transfer rate and total evaporating rate.
The other part of the present study is to investigate the phenomenon of natural convection in an enclosure heated from below, fitted with a completely horizontal conductive partition. The upper and lower regions are separately filled with one fluid and one porous layer. The numerical method is based on the SIMPLEC method and solved by the commercial software CFDRC. Parametric studies concerning the effects of the location of partition (HR), aspect ratio (L/H), Rayleigh number (Ra), and conductivity ratio of the partition (kw/keff) on the fluid flow and temperature fields in the enclosure are carried out. Numerical results indicate that number of convective cells is the criterion of heat transfer rate in the enclosure. The more convective cells, the higher the heat transfer rate. In addition, the cases of larger HR and L/H, and higher kw/keff possess higher heat transfer rate.

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