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Modelling heat and mass transfer in a greenhouse: an aid to greenhouse design and climate control for greenhouse rose production in Zimbabwe

(2010)
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Abstract
The main aim of this PhD research was to model heat and mass transfer in a greenhouse in order to simulate the microclimate in a naturally ventilated Zimbabwean greenhouse. The Gembloux Dynamic Greenhouse Climate Model (GDGCM) was adapted, calibrated and validated to predict the microclimate in a naturally ventilated plastic greenhouse with a rose crop (Rosa hybrida) in Zimbabwe. The GDGCM, though very flexible, was developed, calibrated and validated for a soilless culture of tomato plants in large naturally ventilated, multi-span European glasshouses. It was therefore necessary to adapt the model for another crop (roses in this case) and for a naturally ventilated, plastic greenhouse typical in Zimbabwe. The main sub-models modified were the vegetation and ventilation sub-models. The modified vegetation and ventilation sub-models allowed the GDGCM to adequately simulate the climate inside a naturally ventilated commercial Azrom type greenhouse containing a rose crop in Zimbabwe using external climate data as inputs. By using the GDGCM to simulate inside air temperature and humidity, leaf temperature and solar radiation at the top of the canopy using climatological observations, different climate control algorithms and the radiometric properties of different covering materials (and the changes to these properties due to aging, whitening and dust accumulation), quantitative estimates of their effect on greenhouse microclimate and canopy behaviour under conditions typical of horticultural operations in Zimbabwe were obtained. This enabled the model to be used to optimize different greenhouse designs, test the effectiveness of different greenhouse climate management strategies and to estimate the leaf wetness duration in greenhouses in order to forecast the onset of fungal diseases, such as botrytis, downy mildew and powdery mildew, within greenhouse crops. This information can be used by extension workers to help them decide on appropriate greenhouse designs, covering materials, climate management strategies and the precautions to take to prevent possible disease epidemics.
Keywords
ventilation modelling, greenhouse climate modelling, climate modelling, ventilation, greenhouse, climate control, greenhosue microclimate

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Chicago
Mashonjowa, Emmanuel. 2010. “Modelling Heat and Mass Transfer in a Greenhouse: An Aid to Greenhouse Design and Climate Control for Greenhouse Rose Production in Zimbabwe”. Ghent, Belgium: Ghent University. Faculty of Bioscience Engineering.
APA
Mashonjowa, E. (2010). Modelling heat and mass transfer in a greenhouse: an aid to greenhouse design and climate control for greenhouse rose production in Zimbabwe. Ghent University. Faculty of Bioscience Engineering, Ghent, Belgium.
Vancouver
1.
Mashonjowa E. Modelling heat and mass transfer in a greenhouse: an aid to greenhouse design and climate control for greenhouse rose production in Zimbabwe. [Ghent, Belgium]: Ghent University. Faculty of Bioscience Engineering; 2010.
MLA
Mashonjowa, Emmanuel. “Modelling Heat and Mass Transfer in a Greenhouse: An Aid to Greenhouse Design and Climate Control for Greenhouse Rose Production in Zimbabwe.” 2010 : n. pag. Print.
@phdthesis{1061681,
  abstract     = {The main aim of this PhD research was to model heat and mass transfer in a greenhouse in order to simulate the microclimate in a naturally ventilated Zimbabwean greenhouse. The Gembloux Dynamic Greenhouse Climate Model (GDGCM) was adapted, calibrated and validated to predict the microclimate in a naturally ventilated plastic greenhouse with a rose crop (Rosa hybrida) in Zimbabwe. The GDGCM, though very flexible, was developed, calibrated and validated for a soilless culture of tomato plants in large naturally ventilated, multi-span European glasshouses. It was therefore necessary to adapt the model for another crop (roses in this case) and for a naturally ventilated, plastic greenhouse typical in Zimbabwe. The main sub-models modified were the vegetation and ventilation sub-models. The modified vegetation and ventilation sub-models allowed the GDGCM to adequately simulate the climate inside a naturally ventilated commercial Azrom type greenhouse containing a rose crop in Zimbabwe using external climate data as inputs. By using the GDGCM to simulate inside air temperature and humidity, leaf temperature and solar radiation at the top of the canopy using climatological observations, different climate control algorithms and the radiometric properties of different covering materials (and the changes to these properties due to aging, whitening and dust accumulation), quantitative estimates of their effect on greenhouse microclimate and canopy behaviour under conditions typical of horticultural operations in Zimbabwe were obtained. This enabled the model to be used to optimize different greenhouse designs, test the effectiveness of different greenhouse climate management strategies and to estimate the leaf wetness duration in greenhouses in order to forecast the onset of fungal diseases, such as botrytis, downy mildew and powdery mildew, within greenhouse crops. This information can be used by extension workers to help them decide on appropriate greenhouse designs, covering materials, climate management strategies and the precautions to take to prevent possible disease epidemics.},
  author       = {Mashonjowa, Emmanuel},
  isbn         = {9789059894037},
  keyword      = {ventilation modelling,greenhouse climate modelling,climate modelling,ventilation,greenhouse,climate control,greenhosue microclimate},
  language     = {eng},
  pages        = {XVI, 292},
  publisher    = {Ghent University. Faculty of Bioscience Engineering},
  school       = {Ghent University},
  title        = {Modelling heat and mass transfer in a greenhouse: an aid to greenhouse design and climate control for greenhouse rose production in Zimbabwe},
  year         = {2010},
}