Comparison of two infiltration equations with three‐terms expansions consistent with the approach of Philip theory
Year: 2024
Type: article
Abstract: In this study, the approximate three‐term (3 T) one‐dimensional (1D) vertical infiltration equation by Valiantzas (3 T‐V) and the 3 T approximate infiltration equation of the quasi‐exact implicit (QEI) Haverkamp equation (3T‐R) by Rahmati et al. for both direct and inverse modelling of water infiltration into soils were evaluated. The 3 T‐V equation is simpler and involves only two physically meaningful parameters, sorptivity ( S ) and saturated hydraulic conductivity ( K s ), unlike 3 T‐R, which includes an additional parameter, β . The coefficients of the second and third terms of 3 T‐V acquire the same values as those of 3 T‐R for values of the parameter β equal to 0.6 and 1.1, respectively. Both 3 T equations yielded similar cumulative infiltration results except at longer times. The inverse solution of 3 T‐V showed better accuracy in predicting S and K s, with relative error (RE) values generally below 6% and 11%, respectively. The reliability of the S and K s predictions via the 3 T equations improved over time, and both methods yielded nearly identical results across the studied soils at all infiltration times. However, longer times are needed to accurately predict K s . Analysing the contribution of each term reveals that the third term ( t 3/2 ), though minor in total infiltration, extends the validity time of the 3 T equations.
Source: Irrigation and Drainage
DOI: 10.1002/ird.3062
Institution: Agricultural University of Athens
Language: English
Topic: Soil and Unsaturated Flow
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,450
OpenAlex ID: W4404998115