Simulation of the soil wetting shape under porous pipe sub‐irrigation using dimensional analysis

Abstract

Abstract Based on the discharge characteristics test for a porous pipe used widely in greenhouse sub‐irrigation in west Liaoning Province, China, Time Domain Reflectometry (TDR) was applied to monitor the process of soil water movement during sub‐irrigation. A model to determine the soil wetting shape was developed using a dimensional analysis method. Statistical analysis revealed that this model has a high accuracy in simulating the wetted soil shape, demonstrating that there was no significant difference between predicted and observed soil wetted width under different depths. It showed that one simple model could also be used to simulate the shape of the wetting area under a porous pipe sub‐irrigation system, which was expected to provide aids for deciding depth and intervals of pipes and designing a sub‐irrigation scheme. Copyright © 2007 John Wiley & Sons, Ltd.