Posted by Jason Lillywhite
From time to time, we hear from GoldSim users asking about the possibility of linking MODFLOW with GoldSim dynamically. This is important because the combined model is useful for integrating accurate groundwater flow and transport models with decision support, hydrologic, and probabilistic models built in GoldSim. Folks at Barr Engineering were able to pull this off using a realistic hypothetical application and presented their application at the poster session of our 2015 User Conference.
Barr developed a hypothetical yet realistic test case involving contaminant transport via groundwater to a river to test the linkage. What I think is really interesting about this application is that it is fully dynamic, meaning that GoldSim and MODFLOW interact on each time step of the GoldSim simulation. Below is a diagram showing the model linkage.
GoldSim was used to generate all random variables and to model the flow rates and quality of the contaminant source and the receiving water body. MODFLOW and MT3D were used to model the groundwater flow field and the solute transport from the contaminant source to the receiving water body. The test case was run as a transient, Monte Carlo simulation with 40-year duration, monthly time steps, and 50 random realizations. The simulation took approximately 21 hours to run using a single processor but this could be reduced by reducing the number of calls to MODFLOW and/or utilizing GoldSim’s parallel processing capabilities.
A full description of this work, including details of the linkage has been posted in the knowledge base of our library, here. This project was funded by Barr Engineering Company’s Innovation Grants program. For more information, please contact Adam Janzen (ajanzen at barr dot com).