A Computer Software to Design Subsurface Drain and Open Trench as a Hybrid Drainage System for Farmland
LI Huizhen
LI Fahu
ZHOU Xinguo
SHI Xueshuang
ZHANG Wenchao
Abstract：[Objective]Subsurface drain is a common drainage technique to keep groundwater table below a critical depth. The purpose of this paper is to present a model and computer program to help design subsurface drain and open ditch as a hybrid drainage system for farmland.[Method]The model was based on hydrodynamics of soil water and considered both drainage and evaporation; the water flow was solved numerically.[Result]For the cases we studied, considering evaporation allowed the distance between adjacent drains to increase by 2.9％～ 17.3％ compared with scenarios without evaporation; increasing the drain-drain distance from 15 m to 25 m reduced the groundwater table drawdown by 24.7％～27.5％. Increasing the depth of the drain from 1.5 m to 2.0 m enhanced the groundwater table drawdown by 34.8％. Comparison with the literature results showed that the maximum relative errors of the model simulations was less than 1.2％. The code ran fast and, in most circumstances, could give the final results in less than 5 seconds.[Conclusion]The model and the software we developed can be used as a tool to design drainage systems to control soil salinity and to ameliorate waterlogging.
Keywords：subsurface pipe drainagepipe spacingpipe buried depthcalculation modelsoftware programming
Publication Date：2018-01-01
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 101-108 )