Highlights of a GCT run

The pictures on this page are highlights of a particular GCT code run. The pictures have been chosen to illustrate particular aspects of simulator behavior, such as upstream flow and transport of a high-density contaminant.

Depicted are the results of a simulation of groundwater flow. This particular run took 4 days using 56 compute processors on an Intel Paragon. The grid used is 137x129x11. Each time step produced a 777K datafile for 1Gb of total output. The topological data is from an actual site in New England.

The pictures are sometimes oriented differently. Check the Groundwater Flow entry for orientation hints.

Simulation Starts

The comtaminant plume is descending through the groundwater. While most parts of the clay layer directly under the contaminant source are in contact with the pollutant, only high points of the cap are in contact with other than trace amounts.

Timestep: 20
Isosurface Setting: 0.005
Groundwater Flow: from top left

Plume reaches impermiable layer

The contaminant plume is contacting the impermiable clay layer at the bottom of the aquifer. The greenish isosuface, representing the outer edge of the contaminant plume, shows that contamination is confined directly under the polluting site.

Timestep: 120
Isosurface Setting: 0.005
Groundwater Flow: from top left

Pollutant Body at time step 700

There is now a substantial accumulation of high-density pollutant directly on the clay cap. Note the orange area indicating the downflow front.

Timestep: 700
Isosurface Setting: 0.7
Groundwater Flow: from bottom right

Pollutant Limit at time step 800

The outer edge of contamination at time step 800. The groundwater flow has distributed a low level of contamination downflow a significant distance. There has been very little upstream movement of low contaminant concentations.

Timestep: 800
Isosurface Setting: 0.005
Groundwater Flow: from top left

Pollutant Limit at time step 800 -- top view

Top view of the previous picture. Lobes on right edge of the isosurface are due to topology.

Timestep: 800
Isosurface Setting: 0.005
Groundwater Flow: from top left

Pollutant Body at time step 800

The contaminant plume is mostly directly under the contaminant site.

Timestep: 800
Isosurface Setting: 0.6
Groundwater Flow: from top left

Pollutant Lobes downflow at time step 800

We get interesting behavior, such as the separation of the contaminant body into two parts by a "hill" at the front of the flow.

Timestep: 800
X Slice: 77 (of 137)
Groundwater Flow: from top left

Surface Contamination and Low Level Accumulation at time step 800

On the upflow side, the contaminant plume is initially pushed downflow by the water flow. Contaminant accumulation on the impermeable layer allows the contaminant to be present in high levels directly under the pollutant source.

Timestep: 800
X Slice: 86 (of 129)
Groundwater Flow: from top center

Low Level Accumulation and Upstream Flow at time step 800

Again on an upflow side, we see similar behavior. In addition, we see upstream flow. This is particularly clear in the next picture.

Timestep: 800
X Slice: 17 (of 137)
Groundwater Flow: from top left

Upstream Flow at time step 800

The two bumps on the right front edge of the isosurface show low levels of contamination that are present only due to upstream flow.

Timestep: 800
Isosurface: 0.005
X Slice: 17 (of 137)
Groundwater Flow: from right center

Pressure Value at time step 800

The pressure that drives the groundwater flow, as expected, is highest in the corner where the groundwater flow originates.

Timestep: 800
Z Slice: 1 (of 11)
Groundwater Flow: from red corner



Data for the run prepared by Apostol Vassilev, apostol@isc.tamu.edu.


Last update September 13, 2007 by abnersg@math