{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

lec 8 aquifer test

# lec 8 aquifer test - Aquifer Tests Lecture 8(Max Qinhong Hu...

This preview shows pages 1–13. Sign up to view the full content.

Aquifer Tests Lecture 8 (Max) Qinhong Hu ydrogeology Hydrogeology (GEOL 4320 and 5328) Fall 2009

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Outline Water flow in confined aquifers ater flow in unconfined aquifers Water flow in unconfined aquifers Steady radial flow to a well Unsteady radial flow in a confined aquifer Unsteady radial flow in a leaky aquifer nsteady radial flow in an unconfined aquifer Unsteady radial flow in an unconfined aquifer Well capacity, well efficiency, and well skin 2
Mathematical Analyses of Groundwater Flow low equations can be solved by Flow equations can be solved by Analytical approaches m ri l ppr h Numerical approaches Analytical approaches Based on classical methods for solving differential equations Have been used in groundwater applications since the 1930s For simple problems (regular geometry, homogeneous aquifer properties, simple initial 3 and boundary conditions) Use Excel, a calculator, tables of functions

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Mathematical Analyses of Groundwater Flow Numerical approaches Developed in concert with modern computers Tremendously powerful n b ppli d t l t th m t Can be applied to evaluate the most complicated, real-world problems Can handle variability in hydraulic properties, large numbers of wells, and complicated boundary conditions (e.g., variable recharge/evaporation and 4 groundwater/surface water interactions)
Steady Flow in a Confined Aquifer 5

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Steady Flow in a Confined Aquifer 0 2 h 0 0 h h x Laplace equation Steady-state 2 x h h One-dimensional omogeneous aquifer L L x Homogeneous aquifer x h h h h L x ) ( 0 0 h h K q L x 0 6 L L
Steady Flow in a Confined Aquifer 7

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Steady Unidirectional Flow in a Confined Aquifer 2 0 2 x h qx h K h h d The head decreases l q linearly with flow th 8 in the x- direction
Piezometers Potentiometric surface 9

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Confined Aquifer: Example If the distance and observed piezometer surface drop between two adjacent wells are 1,000 m and 3 m , respectively, find an estimate of the time it takes for a molecule of water to move from one well to e other Assume steady unidirectional flow in a homogeneous silty the other. Assume steady unidirectional flow in a homogeneous silty sand confined aquifer with a hydraulic conductivity K=3.5 m/day and an effective porosity of 0.35 . d m d m m hK q / 0105 . 0 000 ) / 5 . 3 )( 3 ( m x ) 1000 ( d m q 3 ) / 0105 . 0 ( d m n e / 03 . 0 ) 35 . 0 ( 000 10 yrs d d m m L t 3 . 91 33333 / 03 . 0 1000
Outline Water flow in confined aquifers ater flow in unconfined aquifers Water flow in unconfined aquifers Steady radial flow to a well Unsteady radial flow in a confined aquifer Unsteady radial flow in a leaky aquifer nsteady radial flow in an unconfined aquifer Unsteady radial flow in an unconfined aquifer Well capacity, well efficiency, and well skin 11

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Steady Flow in an Unconfined Aquifer The gradient of the water table in unconfined aquifer is not constant ; it increases in the direction of flow as the cross-sectional area gets smaller No analytical solution 12 to the Laplace equation
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 106

lec 8 aquifer test - Aquifer Tests Lecture 8(Max Qinhong Hu...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online