本研究利用數值模擬方式研究漸擴流道設計運用於水氣轉移反應薄膜反應器。在較短管長之薄膜反應器中，反應並不完全，然而當薄膜反應器採用漸擴流道設計可提升合成氣滯留時間、薄膜面積於反應端，此外漸擴流道令反應端減速使合成氣擁有更多時間進行反應而氫氣具有更多時間擴散，上述原因導致漸擴流道對薄膜反應氣產生極大的改善。而當反應端出口半徑較大之時，反應端可約略區分為三部分：滲透限制區、過度區、反應限制區，其中滲透限制區由於生成物的缺少導致滲透之影響遠小於反應，過度區則反應與滲透之影響不相上下，反應限制區則是由於生成物的累積導致滲透影響大於反應。總體而言，漸擴流道設計運用於水氣轉移反應薄膜反應器於本研究之操作條件下一氧化碳轉換率以及氫氣回收率皆有所顯著的提升。

This study shows the improvement on the performance of water gas shift reaction membrane reactor with divergent flow channels by numerical simulation. With a short length of membrane reactor, the complete chemical reaction of synthetic gas is not achieved. Both the residence time and membrane area increase in divergent flow channels on the reaction side. The divergent flow channel can slow down the velocity to provide more time to react for synthetic gas and to diffuse for H2. These reasons result in a significant performance improvement on both the reaction and permeation sides. For large reaction side outlet radius, the molar fraction can be separated into three regions: permeation limit, transition and reaction limit. In the region of permeation limit, the influence of reaction is much larger than that of permeation due to the lack of products. The influences of reaction and permeation are nearly equal in the transition region. In the region of reaction limit, the reaction rate is relatively slow because of abundant products. The membrane reactor with divergent flow channels improves the performance not only on CO conversion but also on H2 recovery under the conditions used in the present study.

Abstract I
中文摘要 II
Acknowledgments III
List of tables V
Nomenclature VI
Chapter 1 Introduction 1
Chapter 2 Water gas shift reaction membrane reactor 4
2-1 Literature review 4
2-2 Divergent membrane reactor 6
Chapter 3 Simulation model 7
3-1 Physical model 7
3-2 Mathematical model 9
3-3 Chemical reaction model 12
3-4 Permeation model 14
3-5 Boundary conditions 16
3-6 Numerical model 21
Chapter 4 Results 22
4-1 The influence of pre-exponential factor 22
4-2 The influence of feeding rate 48
4-3 The influence of sweeping gas flow rate 59
4-4 The influence of H2O/CO molar feeding ratio 62
Chapter 5 Conclusions 64
Chapter 6 Future work 65
Chapter 7 References 65
Appendix A - Gas mixture properties estimation 67

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