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http://dx.doi.org/10.12791/KSBEC.2020.29.1.52

CFD Analysis for Microclimate of Venlo Type Glasshouse with the Screen Height and Air-inflow Quantity  

Yang, Won Mo (Department of Horticulture Sunchon National University)
Publication Information
Journal of Bio-Environment Control / v.29, no.1, 2020 , pp. 52-61 More about this Journal
Abstract
The natural change of winter night temperature from 00:00 to 04:30 O'clock with the different height of thermal screen in a venlo type glasshouse (W59×L68×H5.9 m) was studied using computational fluid dynamics (CFD). At the early stage of CFD analysis, the room temperature decrease of glasshouse with the 5.9 m height of thermal screen were faster than it with the 4.1m height of thermal screen, but at 2 hr after analysis it was slower than in it with the 4,1m, the temperature difference was 0.6℃ after 4 hr. If we consider that turn on the heater when the temperature were decrease below 13℃ at 1hr after CFD analysis, it is good for energy saving in the glasshouse with the 4.1 m height of thermal screen rather than in it with the 5.9 m height, because of the temperature decrease were slow during 2 hrs after analysis. The airflow at the height of 2 m which were grown tomato were fast and wide in the glasshouse with the 5.9 m height thermal screen rather than in it with the 4.1 m, the speed difference was 0.034m·s-1 at 1hr after CFD analysis. The effect of temperature decrease in summer season were compared with the different height of shading screen from 12:00 to 14:30 O'clock. The height of shading screen were 5.7, 3.9 m, the gap of it were 30%. The air-inflow quantity by the fan with duct at lower part of venlo glasshouse was 0.67 ㎥·s-1 until 1hr and to increase 3 times of it from 1hr after analysis. The roof window were open 100%. Until 1hr of CFD analysis, the temperature in the 30% open of shading screen was 0.9℃ higher than in the none shading screen. From 13:00 O'clock when the air-inlet quantity to increase 3 times, the temperature in case 30% gap of shading screen were decreased compare with the none shading screen, the temperature difference was 0.5℃ at 14:30 O'clock. The temperature on the floor surface in case 30% gap of shading screen were lower with it's height increase, the temperature difference was 8℃ compare with none shading screen. The relative humidity difference were insignificant by the height and gap of shading screen.
Keywords
computational fluid dynamics; energy saving; greenhouse cooling; screen height; ventilation effect; wind direction;
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  • Reference
1 Davide P. 2012. Analysis of night-time climate in plasticcovered greenhouses. Tesi Doctoral., Universitat Politecnica de Catalunya. p. 6-17, 48-79, 80-109.
2 He, K.S, D.Y. Chen, L.J. Sun, Z.L. Liu, and Z.Y. Huang. 2015. The effect of vent openings on the microclimate inside multi-span greenhouses during summer and winter seasons. Engineering Applications of Computational Fluid Mechanics 9(1):399-410.   DOI
3 Hong, S-W., I-B. Lee, H-S. Hwang, I-H. Seo, J.P. Bitog, J-L. Yoo, K-S. Kim, S-H. Lee, K-W. Kim and N-K. Yoon. 2008. Numerical simulation of ventilation efficiencies of naturally ventilated multi-span greenhouses in Korea. Amer. Soc. of Agricultural and Biological Engineers. 51(4):1417-1432.
4 Hong, S.W and I.B. Lee. 2014. Predictive model of micro-environment in a naturally ventilated greenhouse for a model-based control approach. Protected Horticulture and Plant Factory 23(3):181-191 (in Korean).   DOI
5 Kim, K., J.Y. Yoon, H.J. Kwon, J.H. Han, J.E. Son, S.W. Nam, G.A. Giacomelli, and I.B. Lee. 2008. 3-D CFD analysis of relative humidity distribution in greenhouse with a fog cooling system and refrigerative dehumidifiers. Biosystems Engineering 100:245-255.   DOI
6 Lee, I., S. Lee, G. Kim, J. Sung, S. Sung and Y. Yoon. 2005. PIV verification of greenhouse ventilation air flows to evaluate CFD accuracy. Amer. Soc. of Agri. Engineers 48(5):2277-2288.
7 Lee, I.B and T.H. Short. 2001. Verification of computational fluid dynamic temperature simulations in a full-scale naturally ventilated greenhouse. Amer. Soc. of Agri. Engineers 44(1):119-127.   DOI
8 Liu, S.Z., Y. He, Y.B. Zhang, and X.W. Miao. 2005. Prediction and analysis model of temperature and its application to a natural ventilation multi-span plastic greenhouse equipped with insect-proof screen. Journal of University Science 6(B)(6):523-529.
9 Majdoubi, H., T. Boulard, H. Fatnassi, and L.C. Bouirden. 2009. Airflow and microclimate patterns in a one-hectare canary type greenhouse: an experimental and CFD assisted study. Agricultural and Forest Meteorology 149:1050-1062.   DOI
10 Nam, S.W., Y.S. Kim and D.U. Seo. 2013. Eva;uation of natural ventilation performance for multi-span plastic greenhouse. Protected Horticulture and Plant Factory, 22(1):7-12.(in Korean)   DOI
11 Campen, J.B. 2006. Ventilation of small multispan greenhouse in relation to the window openings calculated with CFD. ISHS 2006 Acta Hort. 718:351-356.
12 Bartzanas, T., M. Kacira, H. Zhu, S. Karmakar, E. Tamimi, N. Katsoulas, I.B. Lee, and C. Kittas. 2013. Computational fluid dynamics applications to improve crop production systems. Computers and Electronics in Agriculture 93: 151-167.   DOI
13 Boulard, T., J.C. Roy, H. Fatnassi, A. Kichah, and I-B. Lee. 2010. Computer fluid dynamics prediction of climate and fungal spore transfer in rose greenhouse. Computers and Electronics in Agriculture 74:280-292.   DOI