Dewatering design

[WBell]

Construction Dewatering and Groundwater Control, Powers, et al., 3rd Ed. lists a summary of analytical models for flow within an aquifer (Table 6.1 attached). I am trying to determine what the factor is that is applied to the basic equation for U.S. units. For example, for the radial flow, confined aquifer model, the value of Qw is given from the basic equation with a factor of 2*pi in the numerator. The equation is listed for U.S. units with a factor of 229 in the denominator. I am trying to determine what units are involved with the factor because on p. 71 of the text there are basic equations given for a rectangular system that accounts for end effects and I would like to factor them correctly.
I would appreciate any comments on how the factors are determined so I can apply the formulas correctly for Eqs (6.10a) & (6.10b).

 

[fel3]

The units for all the variables are provided on the page that you posted. You should be able to analyze the equation with units attached to the variables to see where the 229 (and the other coefficients on the page) come from. To wit, the coefficient 229 equals the number of minutes per day (1,440) divided by 2*pi.

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"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[geotechguy1]

Looking at the units noted at the bottom it looks like the us customary units are in per minute and per day and the metric ones have flow rates in mins and seconds so likely that is part of the difference, so fel3's point is applicable in some way for all of them