Impact of radial and horizontal airflow fans on single-span greenhouse microclimate and yield

Abstract

No matter where they are located, horticultural plants may be grown thanks to greenhouse technology (Kumar et al. 2021).
In order to maximise agricultural yields, the greenhouse structure allows for partial or complete control over climate variables
such temperature, relative humidity (RH), carbon dioxide (CO2) concentration, solar radiation (SR), and vapour pressure
deficit (VPD) (Sagar and Singh 2023). The main purpose of ventilation is to regulate the quality of indoor air by replenishing
and diluting the air inside a space, changing the temperature, relative humidity, and airflow to attain appropriate thermal
conditions. In contemporary commercial farming, controlling the microclimate and ventilation of greenhouses is essential
since it minimises the need for excessive pesticides and herbicides, conserves water, and uses less energy (Akrami et al.
2020). In order to reduce the risk of disease and to achieve uniformity in critical factors like temperature, RH, VPD, and CO2
level within greenhouses, fans must be placed to create air movement that mixes the air and facilitates the evaporation of
moisture from leaf surfaces (Akpenpuun et al. 2022, Randhe et al. 2022). The horizontal airflow fan (HAF), which is placed
horizontally above the crop canopy, is the most often utilised air circulation fan. The radial airflow fan (RAF), which is
positioned vertically above the crop canopy and has one end that extends to the surrounding atmosphere, is a more modern
invention. The impact of HAF on climatic factors has been the subject of several research. Nevertheless, little is known about
the use of RAF and how it affects crop production and the distribution of microclimatic factors. This study's goals were to
examine the efficacy of the HAF and RAF and look into how the RAF affected the distribution of microenvironment factors
and strawberry production.