The year-round rising demand for fresh, high-quality vegetables has driven rapid growth in South Korea’s protected horticulture since the 1990s, resulting in widespread greenhouse installations across South Korea. However, maintaining optimal indoor environmental conditions in greenhouses remains challenging owing to extreme seasonal variations. During summer, indoor temperatures may exceed 35 °C despite active cooling systems; meanwhile, large temperature gradients between the indoor and outdoor environments require effective heating strategies in the winter. A key technology for stabilizing crop productivity and mitigating spatial environmental imbalances is the use of air circulation fans, which promote uniform distribution of temperature, humidity, and CO2. This study investigates the airflow dispersion characteristics of agricultural circulation fans using computational fluid dynamics (CFD) simulations to support improved airflow distribution within greenhouses. The target facility was a multi-span Venlo-type greenhouse. Six circulation fans were installed 5.8 m above the ground, and their airflow patterns were analyzed under different layout scenarios, including uniform spacing and zigzag arrangements. The results showed that a single fan generated an effective airflow area of up to 193.14 m2 and a dispersion distance of 60.34 m. When all fans were aligned in the same direction, airflow distribution was less efficient compared with configurations where central fans were reversed or installed in a zigzag pattern. Specifically, staggered arrangements improved the overall airflow distribution, with the volume-averaged air velocity increasing from 0.290 to 0.369 m/s. The study concludes that fan installation spacing and arrangement significantly influence airflow distribution and uniformity in greenhouses.
Kang et al. (Tue,) studied this question.