Download User`s Manual

α=
A
lV
with
Α: Surface of the matrix block
V: Matrix volume
l: characteristic block length
At the beginning of the pumping test, the water is pumped from storage in the fracture
system; the matrix blocks does not affect the flow. Midway through, the flow to the well is
augmented by water released from the matrix, while the drawdown in the matrix is small
compared to drawdown in the fractures. Towards the end of pumping, the drawdown in the
matrix approaches the drawdown in the fractures, and the aquifer behaves like a single
porosity aquifer with the combined property of the matrix and the fractures (i.e. the
drawdown follows the Theis curve).
An example of a Warren Root, Double Porosity analysis graph has been included below:
In this example, the dimensionless view is shown. An example of a Fracture Flow analysis
is available in the project: AquiferTest\Examples\Fractured.HYT.
The Warren Root solution requires the following data:
• Drawdown vs. time data at an observation well
• Distance from the pumping well to the observation well
• Pumping rate
Dimensionless parameters
AquiferTest uses the dimensionless parameters, s and L, which characterize the flow from
the matrix to the fissures:
172
Chapter 4: Theory and Analysis Methods