A Bayesian Assessment of an Approximate Model for Unconfined Water Flow in Sloping Layered Porous Media

Chiach�o, Juan; Chiach�o, Manuel; Sankararaman, Shankar; Prescott, Darren

Abstract

© 2018, The Author(s). The prediction of water table height in unconfined layered porous media is a difficult modelling problem that typically requires numerical simulation.This paper proposes an analytical model to approximate the exact solution based on a steady-state Dupuit–Forchheimer analysis.The key contribution in relation to a similar model in the literature relies in the ability of the proposed model to consider more than two layers with different thicknesses and slopes, so that the existing model becomes a special case of the proposed model herein.In addition, a model assessment methodology based on the Bayesian inverse problem is proposed to efficiently identify the values of the physical parameters for which the proposed model is accurate when compared against a reference model given by MODFLOW-NWT, the open-source finite-difference code by the U.S. Geological Survey.Based on numerical results for a representative case study, the ratio of vertical recharge rate to hydraulic conductivity emerges as a key parameter in terms of model accuracy so that, when appropriately bounded, both the proposed model and MODFLOW-NWT provide almost identical results.

Citation

Chiachío, J., Chiachío, M., Sankararaman, S., & Prescott, D. (2019). A Bayesian Assessment of an Approximate Model for Unconfined Water Flow in Sloping Layered Porous Media. Transport in Porous Media, 126(1), 177-197. https://doi.org/10.1007/s11242-018-1094-2

• Journal Article Type: Article
• Acceptance Date: May 24, 2018
• Online Publication Date: Jun 9, 2018
• Publication Date: Jan 15, 2019
• Deposit Date: Jun 19, 2018
• Publicly Available Date: Jun 19, 2018
• Journal: Transport in Porous Media
• Print ISSN: 0169-3913
• Electronic ISSN: 1573-1634
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 126
• Issue: 1
• Pages: 177-197
• DOI: https://doi.org/10.1007/s11242-018-1094-2
• Keywords: Dupuit–Forchheimer analysis; Layered porous media; Bayesian hypothesis testing; Railway track drainage; General Chemical Engineering; Catalysis
• Public URL: https://nottingham-repository.worktribe.com/output/936848
• Publisher URL: https://link.springer.com/article/10.1007%2Fs11242-018-1094-2
• Additional Information: Received: 30 November 2017; Accepted: 24 May 2018; First Online: 9 June 2018
• Contract Date: Jun 19, 2018