In order to improve crop quality and reduce consumption of water, energy and fertilizer in greenhouses, it is crucial to have a precise knowledge of the internal distributed climate. During the day, because of the path of the sun, there are important variations in the amount of solar radiation reaching the crop, which strongly impacts climate and therefore crop activity. Up to now, this mechanism was scarcely considered in CFD studies. In this work, a 2D pseudo-unsteady CFD approach is implemented to compute the radiation, temperature and humidity variations at plant and greenhouse levels during a solar day in summer. The studied greenhouse is a Venlo glasshouse containing an Impatiens crop under oceanic temperate conditions. The Navier-Stokes equations were solved using the standard k-epsilon turbulence model and a bi-band radiative submodel distinguishing short and long wavelength radiations was employed. A user-defined crop submodel including the aerodynamic drag of the crop considered as a porous medium as well as the sensible and latent heat exchanges occurring at plant level were included. Boundary conditions were set each hour, with varying radiation intensity, diffuse fraction and direction, soil heat flux and inlet temperature. The model makes it possible to assess the climate evolutions of the air and leaf temperature distributions inside the greenhouse.
