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Sun drying is the oldest way to preserve but also to valorize and store surplus agricultural production. Nowadays, several types of dryers have been developed, but the solar greenhouse dryer is an ideal solution in our tropical countries because of its implicit and higher load capacity. The greenhouse climate depends on several factors, namely the outdoor climatic conditions (air temperature, wind speed, radiation, etc.) but also on the type of materials used to cover the greenhouse. The study was carried out on a parabolic greenhouse covered by a polyethylene film with a concrete base (absorber) which in turn is placed on the ground and will be tested under the climatic conditions of Dakar, Senegal. It is in this context of sustainable development that this work is carried out. The goal is to determine the distribution of temperatures and wind speeds in the greenhouse. The simulation was carried out using the three-dimensional computer fluid dynamics software (CFD). The turbulence method (k-ε) was used and to solve the radiation transfer equation (RTE) we introduce the discrete ordered method DO. We also add the “Solar Load Model” which gives the position of the sun and its radiations in relation to the layout of the greenhouse according to the date and time of the simulation. The simulation is carried out in a closed greenhouse and the results found can be used to improve the design and control of the greenhouse climate. Air temperatures and velocities simulation give an average of 325.95 K and 0.114 m/s respectively.

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Sun-drying is the oldest way to preserve, store and also to enhance the value of our agricultural production. Nowadays, several types of dryers have been developed but the greenhouse is an ideal solution for drying in our tropical countries because the sun is abundant. But the control of the greenhouse climate depends on several factors, namely the external climatic conditions but also the type of materials used in the greenhouse. The study was carried out in a greenhouse, tested under the climatic conditions of Dakar. It is in this context of sustainable development that this work, whose objective is to contribute to the improvement of drying conditions for agricultural products, is carried out and to achieve this, the distribution of temperatures and speeds in the greenhouse must be determined. For the three-dimensional CFD simulation, we added a discrete radiation model to solve the radiation transfer equation and the Solar Load Model which gives the position of the sun and its radiation. The simulated air temperatures give an average of 52.8°C with average air velocities that are around 0.114 m/s in the closed greenhouse and the results found can be used to improve the design and control of the greenhouse climate.