NEW version of HGS PREMIUM October 2026 (REVISION 3021)
Support Ongoing Improvements to HGS
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The HydroGeoSphere Revision 3021 (October 2026) is now available for download.
This month’s update focuses on improving transport mass balance accuracy, boundary condition handling, and simulation restarting, while introducing a new control volume weighting option for nodal flux boundary conditions. Together, these updates improve the reliability of flow and transport simulations and provide greater control when distributing specified fluxes across boundary condition nodes in HydroGeoSphere (HGS).
New boundary condition command uniform control volume weighting
The new command uniform control volume weighting applies to the flux nodal and flux nodal from outlet boundary conditions.
This command allows a specified total flux to be uniformly distributed across all boundary condition nodes using a volume-weighted average over the nodal control volumes, providing additional flexibility when defining nodal flux boundary conditions.
hgs2vtu cumulative time series update
Added the raw mass balance files prefixo.mass_balance_raw.species.dat to cumulative time series processing in hgs2vtu.
This expands the transport mass balance information available through hgs2vtu post-processing workflows.
Improved flow boundary condition contributions to transport
Fixed issues related to the incorrect accounting of fluxes at overlapping nodes when flow boundary conditions contribute to transport calculations.
This improves the accuracy of transport simulations where multiple boundary conditions overlap.
Improved sorbed mass calculations
Fixed a bug in the computation of sorbed mass in the surface domain.
Transport mass balance calculations have also been updated to correctly account for surface and fracture sorbed mass, providing more complete mass balance reporting.
Transport mass balance improvements
Fixed an issue in transport mass balance accounting when the control volume approach is active and flow boundary conditions overlap with a specified third-type concentration boundary condition.
Affected flow boundary conditions include:
rain
flux
flux nodal
flux nodal by pressure
flux nodal outlet
fluid transfer
These updates improve transport mass balance calculations when boundary conditions are withdrawing water from overlapping nodes.
Fix for specified third-type concentration boundary conditions
Resolved a bug affecting the specified third-type concentration boundary condition when applied to the surface domain, where total inflow from flow boundary conditions could be calculated incorrectly.
This ensures more accurate concentration boundary condition calculations in the surface domain.
Documentation updates
The HydroGeoSphere Reference Manual (hydrosphere_ref.pdf) has been updated to include these new features and enhancements.
You can find details about these new features in the HydroGeoSphere Reference Manual. And as always, we are committed to the continued improvement of the user experience. Do you have suggestions for new commands or improvements to the user experience? Send your ideas to support@aquanty.com