A Steady-State Model to Simulate Groundwater Flow in Unconfined Aquifer

Abstract

The hydraulic and hydrogeological features of the Caposele aquifer have been investigated by using a numerical groundwater flow model. In particular, groundwater flow simulations were performed for a multilayered, unconfined aquifer in steady-state conditions for different thicknesses of the aquifer’s saturated zone. The Caposele groundwater model was carried out starting from a generic model drained by a unique spring outlet in accordance with the geo-hydrological features of the study area. The conceptual model was built considering hydrogeological features of spring catchment, and was then implemented with the MODFLOW numerical code. A combined 2D-3D approach was adopted, and the model was calibrated on borehole data available for the time period 2012–2019. Different thicknesses of the aquifer were set, and a reliable relationship was found between the hydraulic head, saturated zone and hydraulic conductivity of the aquifer. Using the MODPATH package, the mean travel time (Darcian) of groundwater was computed for five different scenarios, corresponding to the model’s depths; the analysis that was performed shows that the travel time is higher for a greater and lower for a smaller thickness of the aquifer’s saturated zone, respectively. The Caposele aquifer model was zoned in different sectors, named flow pipe areas, that play different roles in groundwater recharge-discharge processes. A vector analysis was also carried out in order to highlight the ascendant flow near the spring zone.

Long-term trends in karst spring discharge and relation to climate factors and changes

“…The period of high flow occurs in spring or summer season, after a time lag with regard to the rainy season, and is connected to a long period of antecedent cumulative rainfall. A numerical model of the Caposele spring catchment was provided by Pagnozzi et al (2020), where groundwater flow paths and velocity in the saturated zone were discussed.…”

Hybridization of DRASTIC Method to Assess Future GroundWater Vulnerability Scenarios: Case of the Tebessa-Morsott Alluvial Aquifer (Northeastern Algeria)

“…On the other hand, the hydrogeological modeling approach remains an important tool to grasp the objectives of groundwater management in different sectors: irrigation, drinking water supply and industry. Numerical modeling is a very practical tool and is often used by researchers for the study of groundwater flows [29] and contaminant flows in aquifers [30]. It has been used in groundwater vulnerability assessment but is usually confined to a small area since it requires an over-parametrization of the aquifer system.…”

Steady State Response of Linear Time Invariant Systems Modeledby Multibond Graphs

“…The steady state response is an important characteristic of a system; for example, some equipment in electrical machines or in power electrical systems requires to know the steady state values for calibration. An interesting steady state reference to simulate groundwater flow in unconfined water can be found in [2]. Furthermore, a modified polynomial expansion algorithm for solving the steady state Allen-Cahn equation for heat transfer processes was proposed in [3].…”