Numerical investigation of greenhouse climate considering external environmental factors and crop position in Sfax central region of Tunisia

Abstract

This paper presents a comprehensive study on the influence of external factors and the crop positioning on indoor environments in Sfax, a central region of Tunisia, during summer climate conditions. To achieve this, an experimental setup is implemented, and a numerical model was developed. The model incorporates air, crops, and soil components to analyze their individual and combined effects on the indoor environment. The numerical results were validated through a comparison with test data obtained from a greenhouse prototype, specifically concerning air velocity and temperature profiles. An optimization of the numerical model was performed considering turbulence and radiation models and grid independence analysis to ensure accurate simulations. Moreover, both with and without crops configurations as well as the impact of the crop position were investigated through a series of numerical simulations. Based on the numerical and experimental findings, the study establishes robust correlations to capture the variations resulting from these factors. The study reveals that external factors, such as ambient air temperature and solar radiation, play a crucial role in determining the temperature inside the greenhouse. The comparative study revealed an increase of less than 1% with the integration of crops in the greenhouse. The central position of the crop emerged as optimal, resulting in a slight temperature reduction of around 2 K compared to the left and right positions. Overall, this study provides valuable insights into the impact of external factors on greenhouse climates and highlights the importance of accurate modeling and control for optimal agricultural management in the central region of Sfax, Tunisia.