Evaluation of HYDRUS- 2D/3D in Water Infiltration Simulation into Soil with Different Textures via Inverse Solution

In recent years, inverse numerical solution methods have been considered by many researchers to address the problems of water movement in soil. In this study, HYDRUS-2D/3D software was used to simulate water infiltration through double-rings infiltrometers in soils with different textures using the inverse solution approach. For this purpose, the infiltration data obtained by double-rings method from 63 points of different regions in Isfahan were used as model input. The studied soils were classified into seven textural classes including Sandy Loam (SL), Sandy Clay Loam (SCL), Loam (L), Silty Loam (SiL), Clay Loam (CL), Silty Clay Loam (SiCL) and SiC (Silty Clay). Good agreement was observed between the measured and simulated cumulative infiltration data, in all soil textures. Coefficients of determination (R2) were 0.998, 0.999, 0.992, 0.996, 0.983, 0.976 and 995 for SL, SCL, L, SiL, CL, SiCL and SiC textures, respectively. Increasing the percentage of clay in the soil textures increased the simulation error. The highest simulation error was observed in SiC (NRMSE = 0.045) and the lowest simulation error was observed in SL (NRMSE = 0.015). In general, the simulated double-rings infiltration data using HYDRUS -2D / 3D software and the inverse numerical solution approach had acceptable accuracy and high reliability in all studied textures.