A computational fluid dynamics investigation of flow, solar radiation, heat transfer, transpiration and condensation in a greenhouse

In this paper we present a 3D computational fluid dynamics (CFD) model which is utilized to evaluate flow in a greenhouse of real spatial extension including solar radiation, heat transfer, transpiration and condensation. The complex and comprehensive model set up comprises outer glass walls, incoming radiation by the sun, heat and radiation sources due to lamps, forced convection by a novel ventilation concept called Multifan V-FloFan, a screen, porous media modelling flow through tomato crop, a transpiration model for the tomato crop, a condensation model coupled to the outer glass walls, open windows as well as convective and radiative heat transfer with the surrounding. All boundary conditions including for the moving sun were chosen for a greenhouse located in the city of Venlo in the Netherlands. The 11.3 million cell mesh allowed a high spatial resolution and a moderate time discretization. We found a uniform mixing of the air with the novel ventilation system and a slight increase in the humidity in one part of the greenhouse due to the effect of open windows.