Experimental Evaluation of Anti-Rain Agricultural Nets: Structural Parameters and Functional Efficiency

Plastic agrotextiles are increasingly used in modern agriculture to protect crops from adverse climatic events, such as excessive rainfall, wind, and solar radiation. Among these, anti-rain nets represent a promising solution to mitigate rain-induced disorders, such as fruit cracking, especially in crops sensitive to water excess. This study investigates the structural and functional properties of eight agrotextiles, including both anti-rain and anti-insect nets. The analysis focuses on geometric characteristics (porosity, thread diameter, mesh density) and on functional performance through experimental evaluation of air and rainwater permeability under different slope conditions. Air permeability was assessed using a wind tunnel, while rainwater permeability was tested via a rainfall simulation bench. The results demonstrate a stronger correlation between the air permeability index (Ka) and the rainwater permeability index Φrw (R2 = 0.95–0.99), across different net slopes (10° and 30°), than between the net porosity and Φrw (R2 = 0.86–0.92). These findings emphasize the greater explanatory power of the dynamic performance indicator Ka as a predictor of rainwater permeability, over purely geometric descriptors like porosity, since it inherently accounts for the dynamic performance of the air flow through the net. This contributes to the development of more effective and sustainable net-based crop protection systems tailored to specific environmental and agronomic needs.