Simulation and Interpretation of the BIBI Ratio CB (.), as a Function of Thermal Parameters of the Low Inertia Polyethylene Wall of Greenhouses

The conventional agricultural tunnel greenhouse is highly widespread in Mediterranean countries, despite the shortcomings it presents, specifically the overheating during the day and the intense cooling at night. This can sometimes lead to an internal thermal inversion. The chapel-shaped glass greenhouse is relatively more efficient, but its evolution remains slow because of its investment cost and amortization.The thermal behavior of a greenhouse has often been studied, mainly during the night. In order to contribute to a better climatic management of the greenhouse, we proposed to develop a thermal analysis model. In this work, a ratio called BIBI was developed to characterize the covering material. This thermal evolution state depends on the degree of air-tightness of this covering material and its physical characteristics. It has to be transparent to solar rays, and must as well absorb and reflect infrared rays emitted by the soil. This leads to trapped solar rays, called the “greenhouse effect”. In this paper we propose the modeling and analysis of the thermal behavior of the polyethylene (PE) wall of the experimental tunnel greenhouse.