Modeling Two-Dimensional Infiltration with Constant and Time-Variable Water Depth

Abstract

Water infiltration is simulated by obtaining the time infiltrated depth evolution and humidity profiles with the numerical solution of the two-dimensional Richards’ equation. The contact time hypothesis is accepted in this study and used to apply a unique form on time of the water depth evolution in the solution domain (furrow), as boundary condition. The specific form of such evolution in time was obtained from results reported in the literature based on the internal numerical full coupling of the Saint-Venant and Richards’ equations in border irrigation. Moreover, the equivalent hydraulic area between the border and the furrow was achieved by scaling the values of water depth. The analysis was made for three contrasting soil textures, and the comparison was done by computing the root mean square error (RMSE) indicator. The comparison was performed from the selection of five finite element meshes with different densities to discretize the solution domain of the two-dimensional Richards’ equation, combined with several time steps. Finally, a comparison was made between infiltrated depth evolution calculated with a constant water depth in the furrow to the one proposed in this work, finding important differences between both approaches. To expand the scope of this study and for a fuller exploration of the subject, the results were compared with results obtained by applying the HYDRUS-2D software. The results confirm that it is important to consider an internal full coupling of the Saint-Venant and Richards´ equations to improve furrow irrigation simulations.

Modelling of the Complex Groundwater Level Dynamics during Episodic Rainfall Events of a Surficial Aquifer in Southern Italy

“…The results of the proposed infiltration model have been compared with the outputs of numerical simulations using the Brooks and Corey based Richards' equation for a one-dimensional domain [41]. Infiltration occurs though the silty clay layer (5 m thick).…”

Fractional Vertical Infiltration

“…Likewise, water infiltration has been used to calculate infiltrated depth evolution and humidity profiles by coupling the Saint-Venant and Richards equations with furrow boundary conditions [17]. Considering this model, the relationship between the optimal irrigation flow and the length of the border for different types of soil was found [18].…”

Numerical Solution of the Two-Dimensional Richards Equation Using Alternate Splitting Methods for Dimensional Decomposition

“…For solving the 2D and 3D Richards equations, a variety of numerical algorithms based on the finite difference (FD) [3][4][5], finite element (FE) [6][7][8], and finite volume (FV) methods [9][10][11][12] have been proposed. Among the aforementioned methods applied for solving multi-dimensional flow problems, it is necessary also to distinguish coupled algorithms, such as the control-volume FD scheme [13], the mixed FE scheme [14][15][16], and the approach based on semi-discretization, in the form of the method of lines (MoL) and transversal method of lines (TMoL) [17].…”