Effects of Vent Configuration and Span Number on Greenhouse Microclimate under Summer Conditions in Eastern China

	Effects of Vent Configuration and Span Number on Greenhouse Microclimate under Summer Conditions in Eastern China
	He, Keshi 1; Chen, Dayue 1; Sun, Lijuan 2; Huang, Zhenyu 1; Liu, Zhenglu 3
刊名	INTERNATIONAL JOURNAL OF VENTILATION
	2015
卷号	13 期号:4 页码:381-395
关键词	natural ventilation CFD simulation multi-span greenhouses vent configuration span number
ISSN号	1473-3315
通讯作者	He, Keshi
英文摘要	The effects of vent configuration and span number on the microclimate in multi-span greenhouses were investigated. A three-dimensional (3-D) computational fluid dynamics (CFD) model was constructed based on an 11-span plastic greenhouse cultivated with 0.2 m-high lettuces. The model was verified with the temperature profile measured in the greenhouse. Then, it was used to explore the effects of vent configuration and span number on greenhouse climate. Simulations show that different vent configurations result in very different microclimate fields. Roof plus side opening has the best cooling and homogeneity performance and is thus recommended. The side openings, the first two windward roof openings and the last two roof openings play a central role during the ventilation process. A minor modification of the ventilation system induces a temperature decrease of 0.1 K and a humidity elevation of 0.3% and increases greenhouse climate homogeneity. These simulations also show that the ventilation rate exponentially decays with an increase of span number once side ventilators are opened, whereas it is maintained at 0.028 m(3)m(-2)s(-1) with roof ventilation. Greenhouse climatic parameters and standard deviations are less influenced by span number than vent configuration Finally, an analysis of inside climatic distribution reveals that strong temperature gradients occur from the windward to leeward area and above the ground. Differences of inside air velocity and temperature with and without the crop vary from 0 to 0.6 ms(-1) and 0 to 1.2 K along the horizontal direction at 0.1 m above the ground, respectively. Photosynthetically active radiation (PAR) is symmetrically distributed in the greenhouse.
学科主题	Construction & Building Technology ; Energy & Fuels
语种	英语
出版者	VEETECH LTD
WOS记录号	WOS:000354745900006
内容类型	期刊论文
源URL	[http://111.203.20.206/handle/2HMLN22E/4753]
专题	作物科学研究所_谷物检测中心
作者单位	1.Shanghai Jiao Tong Univ, Lab Complex Dynam Simulat, Dept Instrument Sci & Engn, Sch Elect Informat & Elect Engn, Shanghai 200240, Peoples R China 2.Chinese Acad Agr Sci, Inst Crop Sci, Beijing 100081, Peoples R China 3.Sunqiao Modern Agr Dev Zone, Shanghai Key Lab Protected Hort Technol, Shanghai 201210, Peoples R China
推荐引用方式 GB/T 7714	He, Keshi,Chen, Dayue,Sun, Lijuan,et al. Effects of Vent Configuration and Span Number on Greenhouse Microclimate under Summer Conditions in Eastern China[J]. INTERNATIONAL JOURNAL OF VENTILATION,2015,13(4):381-395.
APA	He, Keshi,Chen, Dayue,Sun, Lijuan,Huang, Zhenyu,&Liu, Zhenglu.(2015).Effects of Vent Configuration and Span Number on Greenhouse Microclimate under Summer Conditions in Eastern China.INTERNATIONAL JOURNAL OF VENTILATION,13(4),381-395.
MLA	He, Keshi,et al."Effects of Vent Configuration and Span Number on Greenhouse Microclimate under Summer Conditions in Eastern China".INTERNATIONAL JOURNAL OF VENTILATION 13.4(2015):381-395.