Airflow patterns and associated ventilation function in large-scale multi-span greenhouses

Understanding airflow patterns in greenhouses is essential for developing o ptimal natural ventilation systems. Experiments of air velocity distributio ns in the vertical and horizontal planes were conducted in a large multi-sp an greenhouse using a customized multi-point, two-dimensional sonic anemome ter system. The experimental results showed that the vertical and horizonta l profiles of normalized interior air velocities were well described by sim ple linear functions (R-2 - 0.55-0.92). Based on the knowledge of airflow p atterns within the greenhouse, a widely used nondimensional ventilation fun ction was revised and then compared with those of similar studies in the li terature.