Geology Reference
In-Depth Information
Table 2:
Parameters used to calibrate the slug test model,
according to Figs 3 and 4
Calibration test
Case 4
Case 5
Density set 1 (frac/m
3
)
0.004
0.0033
Density set 2 (frac/m
3
)
0.004
0.0033
Density set 3 (frac/m
3
)
0.006
0.005
K-1 (ms
-1
)
1.2 × 10
-2
1.0 × 10
-2
K-2 (ms
-1
)
1.2 × 10
-2
1.0 × 10
-2
K-3 (ms
-1
)
1.2 × 10
-2
1.0 × 10
-2
1.0 × 10
-3
1.0 × 10
-4
S-1(-)
2.0 × 10
-2
8.0 × 10
-3
S-2(-)
2.0 × 10
-2
8.0 × 10
-3
S-3(-)
UPSCALING THE TRANSMISSIVITY AND STORATIVITY
PARAMETERS
Objectives
The upscaling phase of this study consists in a numerical derivation of
equivalent hydraulic parameters at a spatial scale greater than the one
investigated by the slug tests. The aim is to evaluate properties at the scale
of an elementary cell of a global hydrogeological model based on standard
porous media theory. The set of calibrated parameters, at the local scale, will
be directly used for this purpose.
Method
The method consists in simulating parallel flow through a square cell of
varying size. The size of this elementary cell is set successively to 50 m ×
50 m × 30 m and 100 m × 100 m × 30 m, the sides of which are parallel
to east-west and north south directions. Such a cell is filled with fracture
elements, with geometrical properties directly inferred from the previous
calibration phase. The flow is established across the cell, by assigning a head
gradient between two opposite faces, the two others remaining closed to
flow. The head gradient can be applied along X axis and Y axis in two
successive runs.
Because the hydraulic regime is calculated in transient conditions, the
numerical experience has to last until a quasi steady state situation is reached.
Practical numerical prescriptions are as follows:
