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| CFD Based Study of Heterogeneous Microclimate in a Typical Chinese Greenhouse in Central China |
| WANG Xiao-wei, LUO Jin-yao , LI Xiao-ping |
| State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, P.R.China |
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摘要 Indoor microclimate is important for crop production and quality in greenhouse cultivation. This paper focuses on microclimate study based on a computational fluid dynamics (CFD) model of a typical plastic greenhouse (with a sector shape vertical cross-section) popularly used in central China. A radiation model is added into the CFD model so as to simulate coupling of convective transfers and radiative exchanges at the cover and the roof, instead of using the usual coupling approach based on energy balance. In addition, a fractal permeability model is innovatively adopted in the modeling of the crop canopy. Compared the numerical results with measured experimental data, the model simulation is proved with success. This model then is used to explore the microclimate variable distributions in the greenhouse. It shows that the airflow pattern, temperature and humidity profiles are different from those in a sawtooth Mediterraneantype greenhouse. The study suggests that this deliberately developed CFD model can be served as a useful tool in macroclimate research and greenhouse design investigating.
Abstract Indoor microclimate is important for crop production and quality in greenhouse cultivation. This paper focuses on microclimate study based on a computational fluid dynamics (CFD) model of a typical plastic greenhouse (with a sector shape vertical cross-section) popularly used in central China. A radiation model is added into the CFD model so as to simulate coupling of convective transfers and radiative exchanges at the cover and the roof, instead of using the usual coupling approach based on energy balance. In addition, a fractal permeability model is innovatively adopted in the modeling of the crop canopy. Compared the numerical results with measured experimental data, the model simulation is proved with success. This model then is used to explore the microclimate variable distributions in the greenhouse. It shows that the airflow pattern, temperature and humidity profiles are different from those in a sawtooth Mediterraneantype greenhouse. The study suggests that this deliberately developed CFD model can be served as a useful tool in macroclimate research and greenhouse design investigating.
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Received: 25 December 2012
Accepted:
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| Fund: The study was supported by the National Natural Science Foundation of China (50979077). |
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Corresponding Authors:
Correspondence WANG Xiao-wei, Mobile: 13971538700, E-mail: whu1777@yahoo.cn
E-mail: whu1777@yahoo.cn
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Cite this article:
WANG Xiao-wei, LUO Jin-yao , LI Xiao-ping.
2013.
CFD Based Study of Heterogeneous Microclimate in a Typical Chinese Greenhouse in Central China. Journal of Integrative Agriculture, 12(5): 914-923.
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