Experiment on Bimodal Random Field
These photographs show a realization of a bimodal
random permeability field.
Briefly, in work supported by the Subsurface Science Program at the U.S.
Department of Energy, this flow cell was filled to mimic the structure of a
second order stationary random field which had been generated on the computer.
This field was studied in an effort to characterize flow and transport response
in a random porous medium. Results from this series of experiments include
response to pumping (steady state), response of the piezometers to regional
flow, response for chemical tracer tests, and response to injection of microbes
(Arthrobacter).
Instrumentation on this tank included a single inflow reservoir, three outflow
reservoirs, 25 piezometers, and two fully penetrating wells. The light material
in this picture is a fine sand with a hydrualic conductivity of approximately
0.057 cm/sec. The darker material is a coarser sand with a hydraulic
conductivity of approximatley 0.50 cm/sec. The red color is red food coloring,
used as a color tracer, moving with regional flow from the left side to the
right side of this picture. The dye was added as a pulse input in the left
reservoir.
Publications resulting from this effort included:
Silliman, S.E., and
Conwell, P.M., S.E. Silliman, and L. Zheng,
“Design of a piezometer network for estimation of the variogram of the
hydraulic gradient: The role of the instrument”, Water Resources
Research, 33(11), 2489-2494, 1997.