A new numerical benchmark of a freshwater lens

authored by

L. Stoeckl, M. Walther, T. Graf

Abstract

A numerical benchmark for 2-D variable-density flow and solute transport in a freshwater lens is presented. The benchmark is based on results of laboratory experiments conducted by Stoeckl and Houben (2012) using a sand tank on the meter scale. This benchmark describes the formation and degradation of a freshwater lens over time as it can be found under real-world islands. An error analysis gave the appropriate spatial and temporal discretization of 1 mm and 8.64 s, respectively. The calibrated parameter set was obtained using the parameter estimation tool PEST. Comparing density-coupled and density-uncoupled results showed that the freshwater-saltwater interface position is strongly dependent on density differences. A benchmark that adequately represents saltwater intrusion and that includes realistic features of coastal aquifers or freshwater lenses was lacking. This new benchmark was thus developed and is demonstrated to be suitable to test variable-density groundwater models applied to saltwater intrusion investigations.

Organisation(s)

Institute of Fluid Mechanics and Environmental Physics in Civil Engineering

External Organisation(s)

Federal Institute for Geosciences and Natural Resources (BGR)
Helmholtz Centre for Environmental Research (UFZ)
Technische Universität Dresden

Type

Article

Journal

Water resources research

Volume

52

Pages

2474-2489

No. of pages

16

ISSN

0043-1397

Publication date

01.04.2016

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Water Science and Technology

Sustainable Development Goals

SDG 6 - Clean Water and Sanitation

Electronic version(s)

https://doi.org/10.1002/2015WR017989 (Access: Open)