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INPUT   DATA

♥ EXAMPLE Of Input/Output

Title

Bottom width, w		ft
Slope of bank #1, z1
Slope of bank #2, z2
Slope of channel, S
Depth of flow, d		ft
Manning coefficient, n

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OUTPUT   VARIABLES   &   GRAPHS

Variables	Values	Units
♦  Flow rate or discharge, Q		ft3/s
♦  Flow velocity, V		ft/s
♦  Top width, T		ft
♦  Channel area, A		ft2
♦  Wetted perimeter, P		ft
♦  Hydraulic radius, R		ft
♦  Froude number, F

Unsteady State Flow Into Water Wells

Water is pumped out of wells for drinking, irrigation, etc. Also water is pumped into wells for waste disposal, oil reservoir pressurization, etc. It is often necessary to determine the yield, drawdown around a well and the impact on neighboring wells.
Theis has developed an analytical solution for the drawdown of non-steady state flow in confined homogeneous isotropic aquifer. The Theis equation has become the most widely used equation in transient groundwater hydraulics:

where
     Q = discharge rate
     V = mean velocity of flow
     d = depth of flow
     w = width of bed of channel
     z₁ = slope of bank 1, horizontal to vertical
     z₂ = slope of bank 2, horizontal to vertical
     S = slope of channel, vertical to horizontal
     θ = slope of channel in degrees
     T = top width of surface of flowing water
     P = wetted perimeter of cross-section
     R = hydraulic radius of flow cross-section
     n = Manning's roughness coefficient
     F = Froude number: F < 1 => subcritical flow, F=1 => critical, F>1 supercritical

Tips

    ◊ Use link EXAMPLE Of Input/Output  to demo data entry expectations and results; you may edit & use it as starting point

BIBLIOGRAPHY

• Lindeburg MR; 101 Solved Civil Engineering problems; Professional Publications, Inc., Belmot, CA, USA, 2001.
• Hicks TG; Civil Engineering Formulas, Pocket Guide; McGraw Hill, New York, 2002.
• Chaudhry, MH; Open Channel Flow, Prentice-Hall, Inc., Englewoood Cliffs, NJ, 1993