臺灣博碩士論文加值系統

本研究主要以密閉型溫室為對象進行數值模擬分析，探討溫室在太陽熱輻射照射下，溫室水牆運作及停止時，熱輻射對溫室內部所產生之溫室效應的影響進行模擬；模擬過程中主要使用DO熱輻射模式，調整太陽黑體放射率、材質的吸收係數及漫射分率三種參數設定，搭配太陽熱輻射量對於地面溫度變化之模擬，以快速選取太陽黑體放射率，並配合實驗量測數據之驗證，以確定模擬之準確性。
由模擬結果可知，當溫室水牆運作時可降低溫室內部溫度，使內部溫度低於環境溫度，並有效抑止溫室效應在溫室內發生；而水牆運作與否對於溫室內部流場趨勢並無太大之影響，但均會在水牆上方形成迴流現象造成熱量之累積；本論文最後將溫室實驗所量測之數據與模擬結果相互比對，兩者間溫度最大誤差位於水牆關閉溫室地面處為1.52 %，而溫度最小誤差位於水牆入口處為0.06 %。藉由本模擬結果可作為事先預測溫室內部溫度分佈，使溫室在改良時有參考依據，並減少時間與金錢之浪費。

This research studies the fluid and temperature fields in a close greenhouse under the influence of solar radiation mainly by the means of computational fluid dynamics (CFD). The influence of greenhouse effects due to solar radiation is further understood through simulation for the water wall in the greenhouse is either in operation or totally turned off. By using discrete ordinates (DO) radiation model, the ground temperature changes obtained through CFD approach was compared with the actual measurements. The three most critical input parameters for the DO radiation model including the blackbody emissivity, the absorption coefficient, and the diffusion fraction of material were individually adjusted so that the corresponding CFD results agreed with the measurements. To speed up the process to determine the sun blackbody emissivity, a photometer was used to provide a good initial guess. After that, a simulation was performed using these three parameters and its result was compared with the experimental data to confirm the accuracy of the simulation.
According to the simulation results, a water wall in operation in a greenhouse can effectively reduce the temperature in the greenhouse and therefore restrain the greenhouse effects from taking place in the greenhouse. However, the water wall in operation has very little influence on the airflow in the greenhouse. Regardless of the situations whether the water wall is in operation or not, there exists a flow circulation at the corner between the water wall and the greenhouse roof where heat accumulation takes place and leads to an increase in local temperature. For the case for which the water wall is not in operation, the maximum relative error between several ground temperature measurements in the greenhouse with their associated simulation results was 1.52 %. Furthermore, the minimum relative error was found to be 0.06 % at the velocity inlet on the water wall. Apparently, simulation results can predict the temperature distribution in the greenhouse and can be used as a guide to improve greenhouses without wasting a great deal of time and money.

目錄
摘要…I
Abstract…II
誌謝…IV
目錄…V
表目錄…VII
圖目錄…VIII
符號索引…X
第1章 前言…1
1.1 研究背景…1
1.2 研究動機…2
1.3 文獻回顧…3
第2章 數學模型…7
2.1 統御方程式…8
2.2 紊流模式…10
2.3 多孔隙介質統御方程式…13
2.4 熱輻射模式…15
2.4.1 不透明壁面邊界之定義…16
2.4.2 半透明壁面邊界之定義…18
第3章 數值方法與驗證…20
3.1 數值方法…20
3.1.1 離散化…20
3.1.2 壓力與速度(pressure-velocity coupling)之耦合算法…24
3.1.3 格點系統…25
3.1.4 收斂標準…25
3.2 數值方法驗證…26
3.2.1 實驗數據量測…26
3.2.2 實驗量測結果…29
3.2.3 數學模型驗證…29
3.2.3.1 幾何模型與初始條件…29
3.2.3.2 數學模型與邊界條件…30
3.2.4 數值模擬結果…31
3.2.4.1 幾何模型黑體放射率調整…31
3.2.4.2 材質漫射分率之調整…33
3.2.4.3 玻璃材質吸收係數之調整…37
3.2.5 數值模擬驗證之討論…40
第4章 結果與討論…41
4.1 溫室幾何外型與網格系統…41
4.2 邊界條件設定…43
4.3 數值模擬結果…44
4.3.1 水牆關閉…44
4.3.1.1 溫度分佈情形…44
4.3.1.2 溫室內流場情形…50
4.3.2 水牆啟動…52
4.3.2.1 溫度分佈情形…52
4.3.2.2 溫室內流場情形…58
第5章 結論…61
5.1 結論…61
5.2 未來展望…61
參考文獻…62
作者簡介…65

1.方煒（1998）溫室降溫方法。種苗生產自動化技術通訊，第三期第98004號，第1-19頁。
2.尤建琳（2002）噴霧冷卻法配合擾流風扇於開放式溫室降溫之研究。國立中興大學農業機械工程學研究所碩士論文。
3.李君霞（2005）雙層被覆溫室之結構經濟設計與熱環境模擬研究。國立臺灣大學生物環境系統工程學研究所碩士論文。
4.邱志強（2000）開放型溫室內鼓風式噴霧降溫系統之研究。國立中興大學農業機械工程學研究所碩士論文。
5.連憶菁（2003）水平導風百葉開口部對室內自然通風效果影響之研究。國立成功大學建築學系碩士論文。
6.郭鴻興（2001）以計算流體動力學分析自然通風低層建築物之通風特性。農業工程學報，第47期，第56-66頁。
7.許凱翔（2000）室內流場與濃度場之場模式研究。元智大學機械工程研究所碩士論文。
8.張勝凱（2002）半導體廠災害應變模式之探討。國立臺灣大學機械所碩士論文。
9.黃裕霖（2002）半導體廠潔淨室火場數值模型之研究。國立臺灣大學機械所碩士論文。
10.塑膠布溫室栽培自動化技術手冊，農業自動化叢書第五輯。
11.賴岱巖（2003）台灣地區隧道式雙層塑膠膜溫室設計與環境調節能力研究。國立臺灣大學生物環境系統工程學研究所碩士論文。
12.戴思雯（2005）溫室高度變異對內部熱環境及結構影響之研究。國立中興大學生物產業機電工程學系碩士論文。
13.http://bse.nchu.edu.tw/new_page_9.htm.
14.Bartzanas T., T. Boulard, and C. Kittas (2002) Numerical simulation of the airflow and temperature distribution in a tunnel greenhouse equipped with insect-proof screen in the openings. Computers and Electronics in Agriculture 34: 207–221.
15.Bartzanas T., T. Boulard, and C. Kittas (2004) Effect of Vent Arrangement on Windward Ventilation of a Tunnel Greenhouse. Biosystems Engineering 88(4): 479–490.
16.Bejan A. (1995) Convection Heat Transfer. 2nd. Ed. , New York, John Wiley & Sons.
17.Boulard T., R. Haxaire, M. Lamrani, J. C. Roy, and A. Jaffrin (1999) Characterisation and modelling of the air fluxes induced by natural ventilation in greenhouse. J. Agric. Eng. Res. 74: 135–144.
18.Boulard T., C. Kittas, J. C. Roy, and S. Wang (2002) Convective and Ventilation Transfers in Greenhouses, Part 2: Determination of the Distributed Greenhouse Climate. Biosystems Engineering 83(2): 129–147.
19.Campen J. B., and G. P. A. Bot (2003) Determination of Greenhouse-specific Aspects of Ventilation using Three-dimensional Computational Fluid Dynamics. Biosystems Engineering 84(1): 69–77.
20.Dayana J., E. Dayanb, Y. Strassberg, and E. Presnov (2004) Simulation and control of ventilation rates in greenhouses. Mathematics and Computers in Simulation 65: 3–17.
21.Fath H. E. S. (1994) Transient analysis of naturally ventilated greenhouse with built-in solar still and waste heat and mass recovery system. Energy Convers. Mgmt. 35(11): 955–965.
22.Fath H. E. S., and Khaled Abdelrahman (2004) Micro-climatic environmental conditions inside a greenhouse with a built-in solar distillation system. Desalination 171: 267–287.
23.Fatnassi Hicham, Thierry Boulard, and Lahcen Bouirden (2003) Simulation of climatic conditions in full-scale greenhouse fitted with insect-proof screens. Agricultural and Forest Meteorology 118: 97–111.
24.Francisco Domingo Molina-Aiz, Diego Luis Valera, Antonio Jesús Álvarez (2004) Measurement and simulation of climate inside Almería-type greenhouses using computational fluid dynamics. Agricultural and Forest Meteorology 125: 33–51.
25.Joseph D. D., D. A. Nield, and G. Papanicolaou (1982) Nonlinear equation governing flow in a saturated porous medium. Water Resources Res. Vol. 18: 1049-1052.
26.Kacira M., T. H. Short, and R. Stowell (1998) A CFD evaluation of naturally ventilated multi-span, saw tooth greenhouses. Transactions of the ASAE 41(3): 833–836.
27.Lee I. B., and T. H. Short (2000) Two-dimensional numerical simulation of natural ventilation in a multi-span greenhouse. Transactions of the ASAE 43(3): 745–753.
28.Lee I. B., and T. H. Short (2001) Verification of computational fluid Dynamic temperature simulations in a full-scale naturally ventilated greenhouse. Transactions of the ASAE 44(1): 119–127.
29.Miguel A. F., N. J. Van den Braak, and G. P. A. Bot (1997) Analysis of the air flow characteristics of greenhouse screening materials. J. Agric. Eng. Res. 67: 105–112.
30.Miguel A. F. (1998) Airflow through porous screens: from theory to practical considerations. Energy Building 28: 63–69.
31.Mistriotis A., G. P. A. Bot, P. Picuno, and G. Scarascia Mugnozza (1997a) Analysis of the Efficiency of Greenhouse Ventilation Using Computational FluidDynamics. Agricultural and Forest Meteorology 88: 217-228.
32.Mistriotis A., C. Arcidiacono, P. Picuno, G. P. A. Bot, and G. Scarascia Mugnozza (1997b) Computational Analysis of Ventilation in Greenhouses at Zero-and Low-wind-speeds. Agricultural and Forest Meteorology 88: 121-135.
33.Neilson P. V., A. Restivo, and J. H. Whitelaw (1978) The Velocity C- haracteristics of Ventilated Rooms. Journal of Fluids and Engineering Vol. 100: 291-298.
34.Okushima L., S. Sase, and M. Nara (1989) A support system for natural ventilation design of greenhouses based on computational aerodynamics. Acta Hortic 248: 129–136.
35.Sase S., T. Takakura, and M. Nara (1984) Wind tunnel testing on airflow and temperature distribution of a naturally ventilated greenhouse. Acta Hortic 148: 329–336.
36.Woodruff V. I. (1997) Analysis of vent designs for naturally ventilated gutter connected greenhouses. MS Thesis, Ohio State University, Colombus, OH.