Abstract
The relationship between the air circulation fan installed in a pad-fan evaporative cooled cultivation room of a greenhouse and the air flow properties within a plant canopy was investigated, using a computational fluid dynamics model (CFD). Operating an air circulation fan accelerated the average air flow rate within a plant canopy. However, it also generated an uneven air flow, and according to simulation results, practically no air flow occurred within a plant canopy when the outlet of the fan circulating the air from the pad was faced in the direction of the fan. Placing the inlet of another air circulating fan within the outflow coverage was determined to minimize the unevenness of the air flow for the pad-fan evaporative cooled greenhouses. Maintaining an even air flow within a plant canopy and achieving a suitable air flow within the canopy of a pad-fan evaporative cooled greenhouse with a cultivation area of about 1000 m2, which was the target of the study, were potentially possible by adjusting the outflow rate of the air circulating fan to about 10 m s-1 and installing the next air circulating fan within the coverage of the outflow, as well as adjusting the LAI to about 2.0.
