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研究生:馮英德
研究生(外文):Anh-Duc Phung
論文名稱:空調系統之噴射器參數研究與設計
論文名稱(外文):Design and Parametric Investigation of Ejector in Air-Conditioning System
指導教授:楊勝安楊勝安引用關係
指導教授(外文):Sheng-An Yang
學位類別:碩士
校院名稱:國立高雄應用科技大學
系所名稱:精密模具與機械產研碩士外國專班
學門:工程學門
學類:機械工程學類
論文種類:學術論文
論文出版年:2009
畢業學年度:97
語文別:英文
論文頁數:82
中文關鍵詞:噴射器構造CFD效能
外文關鍵詞:Ejector systemModelingCFDperformance
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噴射器在空調製冷系統中是一個關鍵的零件。它們通常使用在低等的能源驅動循環系統。還具有低維護成本,因為當它們運作時無須壓縮機。重要的是, 噴射器性能直接影響到空調系統的效能。因此,對改善空調系統和製冷系統中的噴射器而言,研究其特性與有效率的設計是重要的課題。在這項研究中,計算流體動力學程式FLUENT,是用來事先模擬噴射器中的流動現象與其性能。


  影響噴射器效率的三個主要參數:產生器、冷凝器和蒸發端溫度。此外,尚需分析噴嘴口位置與其面積比A3/At。CFD 能非常準確的預測噴射器性能,並直接顯示在有效區域中,操作條件對其性能的影響結果。這項研究有助於了解噴射器的特點並提供噴射器設計的信息,以達到最佳條件。
The ejector is a key component in the Air-conditioning and Refrigeration systems. They are usually designed to utilize low grade energy for driving the cycle. They also have low maintenance cost because they operate without a compressor. In particular, the ejector performance directly affects the Air-conditioning systems performance. Therefore, an investigation on the characteristics and an efficient design to the ejector are important to improve ejector in the Air-conditioning and Refrigeration systems. In this study, the computational fluid dynamic (CFD) code, FLUENT, is employed to predict the flow phenomena and performance of ejector.

The influence of three major parameters: generator, condenser and evaporator temperature on ejector efficiency is discussed. Also the position of nozzle exit and the area ratio A3/At is analyzed. CFD can predict ejector performance very well and reveal the effect of operating conditions on an effective area that is directly related to its performance. This investigation helps the understanding of ejector characteristics and provides information for designing the ejector to suit the optimum condition
ABTRACT II
Acknowledgement IV
List of Figure VI
Chapter 1: Introduction 1
1.1 Background 1
1.2 Literature review. 7
1.3 Objectives of the thesis 11
1.4 Layout of the thesis 11
Chapter 2: Mathematical Modeling 13
2.1 Description of the problem 13
2.2 Governing equation 16
2.3 The Ejector in Air-conditioning system Cycle 17
2.4 Calculation of the primary flow through the nozzle 21
2.5 Calculating for the secondary flow 27
2.6 Calculating for cross-sectional area at section y-y (A3) 29
2.7 Calculation for mixing section 29
2.8 Calculations for Constant Area Section 33
2.9 Calculations for Diffuser 34
2.10 Calculations for Performance 35
Chapter 3: Computer Fluid Dynamic Modeling 37
3.1 Fluent Software 38
3.2 CFD Modeling 46
Chapter 4: Result and Discussion 53
Chapter 5 Conclusion and Future work 63
Nomenclature 65
References 70
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22. T. Sankarlal and A. Mani, Experimental investigations on ejector refrigeration system with ammonia, Renew. Energy 2007; 32: 1403–1413

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25.S. Aphornratana, I.W. Eames, Experimental investigation of a combined ejector absorption refrigerator, Int J Energy Res 1998; 22: 195–207
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