矽膠廣泛應用於許多工業製程，像是揮發性有機化合物之吸/脫附、儲能系統等。為了幫助這些工業應用的系統設計，必須了解矽膠在吸/脫附反應的熱質傳特性。目前已經存在之矽膠吸/脫附水汽系列研究中，固體側阻抗(solid-side resistance; SSR)模型因為考量了矽膠之固體側質傳阻抗，故較先前的擬氣體側控制(pseudo-gas-side controlled; PGC)模型更能準確預測反應過程。其中SSR模型又可區分成有考量矽膠顆粒熱傳導阻抗與忽略矽膠顆粒熱傳導阻抗兩種模型。若是前者，則矽膠顆粒內部的溫度分布是會隨著顆粒內部的徑向位置變化。若為後者，則矽膠顆粒即為均勻溫度。在本研究中發現這兩種模型即便在Biot 數小於0.1的條件下，反應結果依然會有些微的差異。具體而言，此差異為忽略熱傳導阻抗的模型其反應結果會有時間的延遲。為了能更加準確預測反應過程，接下來我們皆採用有考量矽膠顆粒熱傳導阻抗的SSR模型做後續的模擬研究。
同時，在先前的研究中，SSR模型僅考慮矽膠填充床軸向的一維變化。在本論文中，我們建立了二維軸對稱矽膠填充床模型；除了原先的軸向還增加徑向的變化，如此一來就能考慮環境對流散熱的效果，並且提升矽膠填充床之吸附速率。因此在本研究有針對環境空氣之對流熱傳係數進行探討，並發現填充床模型尺寸越大，其提升吸附速率效果越明顯。矽膠在吸附水汽會放熱，在脫附水汽時會吸熱，因此亦有針對空氣溫度與濕度進行討論，並發現當進口溫度越低或濕度越高皆會使吸附水汽反應速率加快，若是脫附水汽反應則相反；另一方面我們發現不論是在吸附或脫附水汽反應中，只要固定進口溫度與濕度的大小就能求出反應最終之矽膠含水量，如此將能幫助我們判別矽膠能夠吸/脫附水汽的最大值；此外我們亦發現反應速率會受到矽膠粒徑大小影響，造成此原因為當粒徑越小，單位體積內矽膠總表面積會增大，因此反應速率會加快。

Silica-gel is extensively used in various industrial processes. In order to help design these industrial applications, it is necessary to figure out the heat and mass transfer mechanism during moisture adsorption/desorption process of silica-gel. Previous studies indicate that SSR (solid-side resistance) model, with extra consideration of intraparticle mass transfer resistance, usually can predict more accurately than the earlier PGC (pseudo-gas-side controlled) model does. Furthermore, the SSR model can be categorized into two part, one considers thermal resistance and the other does not. In this study, it is found that these thermal resistances have to be taken into account for Bi > 0.01; otherwise, there were be some time delay in the model. On the other hand, previous research has demonstrated SSR model with 1-D (with axial direction). In this thesis, a 2-D (with both axial and radial directions) silica gel packed bed model is constructed, Therefore it can take the heat convection on the wall of the reactor into account, additionally, enhancing adsorption rate of silica gel. Besides, silica gel releases heat during moisture adsorption process and adsorbs heat during moisture desorption process. As a result, the inlet air velocity and the inlet air moisture play an important role in this study. Furthermore, it is found that decreasing the inlet air temperature or increasing the inlet air moisture makes adsorption rates faster. Besides, whether in adsorption reaction or in desorption reaction, silica gel desiccant water content would be obtained if we know the inlet air temperature and moisture. In addition, it is found that decreasing the particle radius increases surface area per unit volume of desiccant particle and, consequently, enhances adsorption rates of silica gel.

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