Preprints
https://doi.org/10.5194/hess-2018-199
https://doi.org/10.5194/hess-2018-199

  26 Apr 2018

26 Apr 2018

Review status: this discussion paper is a preprint. It has been under review for the journal Hydrology and Earth System Sciences (HESS). The manuscript was not accepted for further review after discussion.

Analysis of Groundwater Response to Oscillatory Pumping Test in Unconfined Aquifers: Consider the Effects of Initial Condition and Wellbore Storage

Ching-Sheng Huang1, Ya-Hsin Tsai2, Hund-Der Yeh2, and Tao Yang1 Ching-Sheng Huang et al.
  • 1State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Center for Global Change and Water Cycle, Hohai University, Nanjing 210098, China
  • 2Institute of Environmental Engineering, National Chiao Tung University, Hsinchu 300, Taiwan

Abstract. Oscillatory pumping test (OPT) is an alternative to constant-head and constant-rate pumping tests for determining aquifer hydraulic parameters without water extraction. There is a large number of analytical models presented for the analyses of OPT. The combined effects of wellbore storage and initial condition regarding the hydraulic head prior to OPT are commonly neglected in the existing models. This study aims to develop a new model for describing the hydraulic head fluctuation induced by OPT in an unconfined aquifer. The model contains a typical flow equation with an initial condition of static water table, inner boundary condition specified at the rim of a finite-radius well for incorporating wellbore storage effect, and linearized free surface equation describing water table movement. The analytical solution of the model is derived by the Laplace transform and finite integral transform. Sensitivity analysis is carried out for exploring head response to the change in each of hydraulic parameters. Results suggest that head fluctuation due to OPT starts from the initial condition and gradually tends to simple harmonic motion (SHM) after a certain pumping time. A criterion for estimating the time to have SHM since OPT is graphically presented. The validity of assuming an infinitesimal well radius without wellbore storage effect is investigated. The present solution agrees well to head fluctuation data observed at the Boise hydrogeophysical research site in southwestern Idaho.

Ching-Sheng Huang et al.

 
Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
 
Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement

Ching-Sheng Huang et al.

Ching-Sheng Huang et al.

Viewed

Total article views: 1,851 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
1,284 545 22 1,851 42 38
  • HTML: 1,284
  • PDF: 545
  • XML: 22
  • Total: 1,851
  • BibTeX: 42
  • EndNote: 38
Views and downloads (calculated since 26 Apr 2018)
Cumulative views and downloads (calculated since 26 Apr 2018)

Viewed (geographical distribution)

Total article views: 1,599 (including HTML, PDF, and XML) Thereof 1,585 with geography defined and 14 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Latest update: 02 Dec 2021
Download
Short summary
A number of analytical models are presented for the analyses of oscillatory pumping test (OPT). The effects of wellbore storage and initial condition regarding the hydraulic head prior to OPT are commonly neglected in existing models. This study aims to develop a new model describing head fluctuation induced by OPT in unconfined aquifers. The effects are analyzed using the analytical solution of the model. Solution prediction agrees well to head fluctuation data observed at a field experiment.