Abstract
In the present study, a theoretical non-gray rigorous model was established to study the radiative heat transfer through greenhouse covering materials by using Radiative Element Method by Ray Emission Model (REM2). This model was applied to find the difference in thermal performances between silica glass, polyvinylchloride (PVC) and low density polyethylene (LDPE) covering materials. Using the advantage of the previously predicted spectral radiative properties of these materials, accurate estimations of greenhouse temperatures were achieved. In addition, an outdoor experiment was conducted to measure the thermal performances of three rectangular enclosures covered by the mentioned claddings. Enclosures inside, floor and cover temperatures calculated using the rigorous model showed a satisfactory correlation with the experimental measurements
