In addition to the mesh-based CCHE3D-GW model, a meshless numerical model, CCHE3D-GW-Meshless has been developed.

Meshless numerical models have recently been developed to circumvent the difficulty in mesh generation to describe groundwater flow in complex geometries. Current meshless numerical groundwater models either only focus on pumping in the fully saturated zone or merely simulate the variably saturated groundwater flow without pumping. However, both pumping and variably saturated groundwater flows are essential components for a groundwater model. As a result, a new three-dimensional model, CCHE3D-GW-Meshless, using meshless weak-strong form method has been developed for the variably saturated groundwater flow with the consideration of pumping/injection.

This is a pumping-induced groundwater drawdown near a river. Both CCHE3D-GW and CCHE3D-GW-Meshless have been verified with this case. It can be seen that the nodes used in the meshless model (CCHE3D-GW-Meshless) distribute more evenly over the domain, whereas for the mesh-based model (CCHE3D-GW), high aspect-ratio meshes can be found which can affect the robustness and accuracy of the simulation.


Note: Please be aware that CCHE3D-GW and CCHE3D-GW-Meshless have not been incorporated into the CCHE GUI interface at this time. Users only need to download ZIP archive of the executable file ‘CCHE3D-GW-beta.exe’ (for the mesh-based model) and ‘CCHE3D-Meshless-beta’ (for the meshless model) and then copy that into the input file folder to run the simulation. We understand that this is not user-friendly, and we are working on building the user interface. We will gradually improve the model based on your experiences, so your comments and feedback will be much appreciated. If you have any questions and/or bug reports, please contact the developer, Jiayu Fang, via email at