Modeling Seepage in Porous Media Using an Unstructured Triangular Finite Volume Algorithm

Document Type : Research Paper

Authors

1 M. Sc. student, Department of Water Engineering, College of Agriculture and Natural Resources, Razi University.

2 Assistant Professor, Department of Water Engineering, College of Agriculture and Natural Resources, Razi University

Abstract

The explorers consider the study of water flow in saturated and unsaturated soils to determine the seepage, pore pressure, uplift force, and hydraulic gradient in the design of dams. Numerical simulation is a rapid low-cost method for the study of soil water flow, which has recently been increased. Many investigators have described approximate methods, based on Dupuit assumptions, to locate the surface of seepage and seepage discharge for different tailwater positions. In order to reduce the seepage discharge and, consequently, flow energy reduction passing the dam, various actions such as the construction of clay core, trench and grout certain, and clay cover on the reservoir floor have been considered. Despite all the measures taken to prevent the movement of water in the embankment dam, water always penetrates the downstream parts due to the permeability of the materials. Drainage systems are designed to collect and direct seepage of water to downstream areas, keeping the dam’s riffle slope dry to decrease the hydroscopic pressure and increase the stability of the embankment dams. Horizontal drains are widely used in homogeneous embankment dams with an average height. In this study, Richards equation was desecrated in two-dimensional and unsteady conditions using an unstructured triangular finite volume algorithm and a computer model developed to simulate seepage in saturated-unsaturated soils. In this model, Van Genuchten equation or other functions can be used to calculate hydraulic conductivity in unsaturated soil for the simulation of flow.

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Main Subjects


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Volume 42, Issue 2
June 2019
Pages 89-103
  • Receive Date: 30 December 2016
  • Revise Date: 20 September 2017
  • Accept Date: 25 September 2017
  • First Publish Date: 22 June 2019