47 T

The value u at the inflection point is tT = = r2S 2T = u = 4Ttj where ti is t at the inflection point. The ratio between the drawdown and the slope of the curve at the inflection point As expressed as the drawdown per unit log cycle of t is derived as

The values of function er/A • Ko(r/A) versus r/A are in Table 9.8.1.

To determine T, S, and c from pumping test data, follow the following procedure:

1. Plot drawdown-time on semilog paper (s-log t).

2. Locate the inflection point P where s = 1/2 X final drawdown.

3. Draw a line tangent to the curve at point P, and determine the corresponding value of ti and the slope As.

4. Substitute s and As values into Equation 9.8(40) to obtain er/A • Ko(r/A), and determine the corresponding value of r/A and Ko r/A from Table 9.8.1.

5. Determine T from Equation 9.8(38).

6. Determine S from Equation 9.8(39).

Project Earth Conservation

Project Earth Conservation

Get All The Support And Guidance You Need To Be A Success At Helping Save The Earth. This Book Is One Of The Most Valuable Resources In The World When It Comes To How To Recycle to Create a Better Future for Our Children.

Get My Free Ebook


Post a comment