熱管熱交換器是非常可靠和有效的裝置。本研究的目的是確定熱管式換熱器在不同輸入條件下的行為，以便對各種情況進行優化和理解。熱交換器採用用於實驗研究的模型進行設計，並用ANSYS Fluent進行模擬，輸入條件與實驗條件相同，以比較和分析其行為。由於環境沒有損失，模擬模型顯示出比實驗模型更好的效率和傳熱，但顯示出相同的趨勢。與0.577的實驗相比，數值模型的最大有效性為0.977。然後通過擴展蒸發器部分的面積並通過向熱管蒸發器添加不同區域的翅片來增強模擬設計。蒸發器部分區域增量和翅片的增加都增加了傳熱，翅片面積增量進一步提高了性能。加入翅片的最大傳熱量為853.3685 W，在相同輸入條件下增加19.7％。

The heat pipe heat exchanger is a very reliable and efficient device. The purpose of this study is to determine the behavior of heat pipe operated heat exchanger in different input conditions to optimize and understand for putting in various situation. The heat exchanger is designed with the model used for experimental research and simulated with ANSYS Fluent with same input condition with experimental conditions to compare and analyze the behavior. The model for simulation shows a better effectiveness and heat transfer then the experimental model due to no loss in the environment, but showed the same trends. The numerical model has maximum effectiveness of 0.977 compared to 0.577 of experiment. The simulation design is then enhanced by extending the area of evaporator section and by adding fins of different areas to the heat pipe evaporator. The heat transfer is increased for both the evaporator section area increment and addition of fins, with the fin area increment further enhanced the performance. The maximum heat transfer with fins added is 853.3685 W, which is 19.7% increase with same input condition.

Acknowledgement	V
Nomenclature	VI
List of Figures	IX
List of Tables	X
Chapter 1 Introduction	1
1.1	History of heat pipe heat exchanger	1
1.2 Literature review	3
1.3 Motivation and Aim of the research	8
Chapter 2 Theory of HPHE and ANSYS Fluent	10
2.1 Case of simulation	10
2.1.1 The Fluent Duel cell mechanism	11
2.1.2 The input conditions and factors	11
2.2 Driving equation and assumptions	12
2.2.1 The Energy equation	12
2.2.2 Assumptions for the case	13
2.3 Theory of heat pipe heat exchanger	14
Chapter 3 Design and Model of Analysis	16
3.1 design of Heat Pipe Heat Exchanger	17
3.1.1 Experimental design of Heat Pipe Heat Exchanger	17
3.1.2 Design for comparison with experimental analysis	18
3.1.3 Design with extended Evaporator section	21
3.1.4 design with Individual Fins	22
3.1.5 design with Combined Fin	24
3.2 Input parameters and Materials	26
3.2.1 Input parameters for different designs	26
3.2.2 Material for the Parts and heat Pipe	28
3.3 Conditions of Simulation	28
3.3.1 Simulation inputs and Requirements	28
3.3.2 Monitors for Result Analysis	29
Chapter 4 Results and discussion	30
4.1 Result and comparison of heat pipe heat exchanger with experiment	31
4.1.1 Comparison of heat transfer	32
4.1.2 Comparison of temperature outputs	33
4.1.3 Comparison of Effectiveness	36
4.2 Result of the heat pipe heat exchanger with variable evaporator length	37
4.2.1 heat transfer with heat transfer area of pipe	38
4.3 Results of the HPHE with Fin	40
4.3.1 Comparison of Individual Fins with Different Areas	42
4.3.2 Comparison of Combined Fin with Individual Fins of Different Areas	43
Chapter 5 Summary	45
5.1 Conclusion	45
5.2 Future work	46
Reference	48
Appendix I	50
Appendix II	51
Fig 1 The basic working mechanism of Heat pipe heat Exchanger	16
Fig 2 Sectional view of Heat pipe heat exchanger	17
Fig 3 Schematic of experimental setup of Heat pipe Heat Exchanger	18
Fig 4 Pictures of the Experimental setup of Heat pipe Heat Exchanger	18
Fig 5 the design of heat pipe heat exchanger with parts and direction of flow	19
Fig 6 Dimensions of the heat pipe and dimension of the inclosing	20
Fig 7 Design of the heat pipe heat exchanger with extended evaporator section.	21
Fig 8 Dimensions of the individual fins with different diameter of fins	22
Fig 9 Heat pipe heat exchanger with individual fins	23
Fig 10 The combined fins with the arrangement mentioned in mm	24
Fig 11 Heat pipe heat exchanger with combined fins	25
Fig 12 Resulting temperature difference shown for different Inlet air velocity	30
Fig 13 Pressure difference for both fluid sections.	30
Fig 14 Velocity profile shown at different Inlet air velocity	31
Fig 15 Comparison of heat transfer from experiment and simulation.	32
Fig 16 Temperature comparison between the Simulation and Experimental value of the heat pipe heat exchanger	35
Fig 17 The effectiveness comparison of simulation and experiment.	37
Fig 18 The heat transfer difference between Lh/L=0.6322 and Lh/L= 0.7290	39
Fig 19 Comparison of the individual fins mounted from number 1 to 10	42
Fig 20 The comparison of the different fins design.	44
Table 1 Different application for heat pipe heat exchanger	3
Table 2 The effective areas of different fins	25
Table 3 Input parameters of Experiment and Simulation	27
Table 4 The area increment of the evaporator section with the addition of fins.	41

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