Comparison of EnergyPlus inside surfaces convective heat transfer coefficients algorithms for energy modelling of high-density controlled environment agriculture

Energy modelling of high-density controlled environment agriculture (CEA-HD) spaces using a building performance simulation (BPS) tool and a crop energy balance model is emerging as a method to conduct load calculation and energy analysis. However, the modelling hypotheses used in BPS tools have yet to be tailored for CEA-HD spaces and might not be suitable for this specific application. This paper investigates the convective heat transfer coefficient (CHTC) algorithms for inside surfaces included in EnergyPlus to examine their applicability to CEA-HD spaces. The influence of these inside surfaces CHTC algorithms on relevant variables are quantified, with computational fluid dynamics (CFD) computed CHTCs as a reference. The results revealed that certain algorithms (Simple, TARP, and ASTMC1340) are ill-suited to model CEA-HD production spaces compared to CFD-computed reference values. Furthermore, due to the modelled flow rate, the Adaptive Convection algorithm resulted in an aberrant value for the ceiling CHTC. This paper highlights the importance of exercising caution when using BPS tools for energy modelling of CEA-HD spaces.