S08 - Session O2 - Analysis of environmental uniformity in a generic multi-layer vertical farm: impact of inlet locations

Authors: Luyang Kang *, Twan van Hooff

Climate uncertainty, rapid urbanization, environmental pollution and public emergency such as the corona-virus pandemic may disrupt the food supply chain for urban residents. Therefore, there is an increasing interest in adopting high-tech precisely controlled environment agriculture, i.e., "vertical farms" or "plant factories", to produce food in a climate-resilient manner. The environmental conditions in a vertical farm are important, since it directly affects the crop yield and quality. However, the uniformity of the environmental conditions in the vertical farm can be poor due to multi-layer cultivation shelves, crop resistance to airflow, and excessive heat generated by artificial lighting. This study investigates the impact of inlet location on environmental uniformity in a generic multi-layer vertical farm using a validated computational fluid dynamics (CFD) modelling approach. In the simulations, the interaction between crops and ambient air is taken into account by porous media. The momentum sink due to the drag effect of the crop is added to the governing equations of air motion. Heat absorption from the crop is considered from an energy balance analysis. Three different inlet locations, i.e., supply air at the height of the crop region, between crops and light-emitting diode (LED) lamps, and at the height of LED lamps, are investigated with CFD simulations. The initial simulation results demonstrate that supply air at the height of crop regions in each layer results in highly non-uniform environmental conditions in crop regions. In addition, the maximum air speed can be very high, which is not favorable to crop growth. Increasing the distance between the air supply and the crop region provides better environmental conditions for crops.