Articles
SIMULATIONS OF THE CLIMATE IN TWO DIFFERENT GREENHOUSES
Article number
719_36
Pages
325 – 332
Language
English
Abstract
The effect of wind speed on the natural ventilation of a multi-span greenhouse and a shark-fin shaped greenhouse were studied and compared by means of two-dimensional computational fluid dynamics (CFD). Both greenhouses were equipped with roll-up windows on the top and the sides.
The validity of this approach was first checked by comparing the numerical results with experimental data obtained from measurements made in full-scale greenhouses without crops.
The experiment was located in a central part of Mexico in the State of Queretaro.
The roof and side ventilation areas for the multi-span greenhouse were 10% and 24% of the ground area covered by the greenhouse and for the shark-fin shaped greenhouse, they were, 30% and 28% respectively.
The simulations were carried out by changing the opening of the windows: totally open, two thirds open and one third open for each greenhouse.
It was taken into account a change in wind direction of 180º. The results showed that the greenhouse air renewal rate at a wind speed of 4 m s-1 and with fully open windows was 75 h-1 for the shark-fin greenhouse, and 27 h-1 for the multi-span greenhouse.
The profile of temperature tended to be more homogenous inside the shark-fin greenhouse, reaching closer to the outside temperature, than inside the multi-span greenhouse.
The validity of this approach was first checked by comparing the numerical results with experimental data obtained from measurements made in full-scale greenhouses without crops.
The experiment was located in a central part of Mexico in the State of Queretaro.
The roof and side ventilation areas for the multi-span greenhouse were 10% and 24% of the ground area covered by the greenhouse and for the shark-fin shaped greenhouse, they were, 30% and 28% respectively.
The simulations were carried out by changing the opening of the windows: totally open, two thirds open and one third open for each greenhouse.
It was taken into account a change in wind direction of 180º. The results showed that the greenhouse air renewal rate at a wind speed of 4 m s-1 and with fully open windows was 75 h-1 for the shark-fin greenhouse, and 27 h-1 for the multi-span greenhouse.
The profile of temperature tended to be more homogenous inside the shark-fin greenhouse, reaching closer to the outside temperature, than inside the multi-span greenhouse.
Publication
Authors
E. Rico-Garcia, J.L. Reyes-Araiza, G. Herrera-Ruiz
Keywords
structural configuration, natural ventilation, wind effect, numerical solution, CFD.
Online Articles (73)