HGS Premium October 2019 (Revision 2068 for Windows/2069 for Linux) 

  1. Update interactive multi-model simulation for transport: 1) 'initial concentration from regional output file' command added and 2) 'specified concentration from hgs run' command for the communication among simulations.

  2. Update transient particle tracing: 'particle tracing' command works for transient flow

  3. Minor bug fix: 1) removing duplicate fractures using SAM, min/max coordinates obtained properly and 2) indexing the tvk_pm output files on model restart using RESTART_FILE_INFO.dat.

HGS Premium September 2019 (Revision 2063 for Windows/2065 for Linux) 

  1. Update GROK to allow for multiple “include” commands in a grok file.

  2. Minor changes and bug fixes: 1) added a message for an error location in reading table values, 2) increased etprop file name length, 3) added olfwall array initialization for every case

  3. NOTE: As of September 2019, HGS (2063 Windows) uses the dynamic libraries (i.e., libifcoremd.dll, libiomp5md.dll, libmmd.dll) for Intel compiler libraries 2019 and thus, HGS (2063 Windows) will not work with older dynamic libraries (e.g., 2057 Windows or before). Please download new dynamic libraries from HERE.

HGS Premium August 2019 (Revision 2057 for Windows/2058 for Linux) 

  1. Update HGS to allow for output file indexes with more than 4 digits.

  2. Pressure-saturation and saturation-relative permeabilities must be sorted in increasing order.

  3. Added latent heat for water and ice properties.

    For your prefix.grok file,

    • thermal conductivity of ice


    • specific heat capacity of ice


    • density of ice


    • latent heat of water


  4. Added an option: ‘write nodal relative permeability for elements’. This option is to output the nodal relative permeabilities for every element (to reconstruct the darcy fluxes for independent particle tracking routines).

  5. Remove deprecated output files: prefixo.vel, prefixo.vel_gb, and prefixo.sat.

  6. Minor bug fixes: 1) improve HGS computation for command combination (e.g., ‘slice flux output nodes from chose’ & ‘slice flux contributing nodes from chosen’), 2) increase the zoned mass balance output buffer for a model with sufficiently many layers, and 3) Introduce the heat_transfer LOGICAL.

HGS Premium July 2019 (Revision 2041 for Windows/2042 for Linux) 

  1. Add new commands: ‘map fractures from mofrac vtk file’. In grok, a feature to identify the fracture faces using MoFRAC fracture network data (VTK format). This new feature supports both triangular and rectangular meshes. Users are required to assign the command and corresponding values in the grok file (prefix.grok).

    Under a fracture domain for your prefix.grok file,

    • map fractures from mofrac vtk file (command)

    • vtk input file name (characters)

    • mapped fracture file name (characters)

    • maximum number of fractures in a vtk input file (maxfracgrp , integer variable)

    • logical variable for visualizing a vtk input file with a tecplot format (logical variable)

    • tecplot ouput file name if true for the input vtk file (characters)

  2. Add new commands: ‘choose nodes polyline by sheet’ and ‘choose nodes polyline top sheet’

  3. Refactor computation of flux through volumes for the flow solution to improve efficiency.

  4. Minor bug fixes: 1) hsplot working without head_pm files, and 2) Minor update to read_olf_zones_from_raster_dominant.

HGS Premium June 2019 (Revision 2030 for Windows/2031 for Linux) 

  1. Manual update (hydrosphere_ref.pdf & hydrosphere_user.pdf): Change name of command to match the manual: choose segments node list -> choose segments am node list.

  2. Bug fix: 1) boundary condition linking (checking no data values for transient flux values specified at an inlet node and changing boundary condition time panel index); 2) particle tracking (assigning lower velocity cutoff values and adding cumulative travel time length).

HGS Premium May 2019 (Revision 2021 for Windows/2022 for Linux) 

  1. Manual update (hydrosphere_ref.pdf & hydrosphere_user.pdf): Grid Builder has been removed from ref and user manuals except when it pertains to GMS.

  2. Added new commands: 1) initial head from regional output file with depth scaling; 2) map zone numbers from regional model by layer; 3) map k from regional model list file by layer; 4) K reduction by impedance factor for chosen elements (see hydrosphere_ref.pdf)

  3. Pruned/renamed grid builder (gb) commands: all gb related commands will be deprecated in the near future. AlgoMesh (am) related commands are commanded.

  4. Bug fix: 1) write_split_mesh_to_tecplot, which splits block elements (nln=8) into tetraedra; 2) checking statement for (nzones_dstar and nzones_prop) and (nspeciesmob and nspec_dstar); 3) Tunnel boundary condition: flow and transport; 4) read polyline and polygon shp files; 5) error checking for command minimum layer thickness. Raises an error if this command is issued outside a new layer block; 6) checking statement for (nzones_dstar and nzones_prop) and (nspeciesmob and nspec_dstar).

  5. Permafrost related commands (‘permafrost porosity’ and ‘permafrost effective diffusion coefficient‘) have been added. In grok, users are required to assign these commands to activate changes in porosities and effective diffusion coefficients of permafrost materials. It should be noted that the changes in permafrost porosity may cause solute mass balance errors when solute transport is performed.

    For your prefix.grok file,

    • interpolate permafrost

    • permafrost formation from file

      For your *.permafrost prop file,

    • permafrost k

      kx ky kz values

    • permafrost porosity

      porosity value

    • permafrost effective diffusion coefficient

      effective diffusion coefficient value

HGS Premium April 2019 (Revision 2005 for Windows/2006 for Linux) 

  1. Update for the regional model mapping feature: 'write all layer nprop files' has been added to write all layer nprop values mapped from a regional model (output file: prefixo.nprop.Sheet_000); 3) minor bug fixed.

  2. 'write separate mass balance for boundary condition link' has been added to write separate output files for boundary condition links: .

  3. ‘effective diffusion coefficient by species’ has been added. In grok, users are required to assign this command to activate unique effective diffusion coefficients by zones and species. The numbers of zones and species are also required in your grok file (prefix.grok). Additionally, effective diffusion coefficients by zones and species should be input in your material property file (e.g., *.mprop).

    For your prefix.grok file,

    • effective diffusion coefficient by species

    • number of zones, number of species

      For your *.mprop file,

    • effective diffusion coefficient list

    • Species 1, Species 2, ..., Species n

HGS Premium February 2019 (Revision 1998 for Windows/1999 for Linux) 

  1. ‘snapshot mean age’ and ‘snapshot mean life expectancy’ commands have been added to compute and output of “snapshot” mean age or mean life expectancy at multiple specified output times for a transient flow simulation. Users are required to assign either of the commands in the grok file. Note: the mean age (or mean life expectancy) model is theoretically based on a steady-state flow condition, but the new commands activate the mean age (or mean life expectancy) calculations with an assumption that the flow condition at an output time is proxy steady state.

  2. Printout ‘nodal ice saturation’ in dual continuum for Tecplot and observation well files when ‘freezing thawing’ and ‘dual continuum’ are activated.

  3. Minor bug fixed: grid mapping and ice saturation dual.

HGS Premium January 2019 (Revision 1989 for Windows/1990 for Linux) 

  1. ‘plot pm depth below ground surface’ command has been added to plot pm depth below ground surface. Users are required to assign the command in the plot control file (prefix.plot.control). In cases where a simulation is performed with an old version of HSPLOT, the new command will not be in the plot control file. To solve this problem, users are required to delete the old plot control file, run HSPLOT (version 1989 or higher), and activate the plot pm depth below ground surface command in the additional post-processing feature section, which is located at the bottom of the plot control file.

  2. ‘maximum number of boundary conditions to report’ has been added (default=100). This command requires an integer number.

  3. Particle tracking feature has been improved by relocating particles in sink holes

  4. Minor bug fixed: change the numer of characters for var_line to max characters per line for Tecplot, which is 32,000.

  5. ‘time varying maximum timestep‘ has been added to assign various maximum timesteps.

    • time varying maximum timestep

    • time(1), maximum timestep(1)

    • time(2), maximum timestep(2)

    • end

HGS Premium December 2018 (Revision 1982 for Windows/1983 for Linux) 

  1. ‘Defined flow’ command has been added to run solute transport simulations without solving flow conditions at each timestep. Once the flow matrix is constructed at the first timestep, HGS uses the flow conditions for the rest of the transport simulations with constant flow conditions, which corresponds to a new term “defined flow” applied for invoking the new simplified solute transport process. To invoke this feature, use ‘defined flow’ after the grid generation is done.

    NOTE: HGS will use the initial and boundary conditions for calculating fluxes at the first timestep and apply the fluxes to the rest of the simulation time steps. Thus, transient boundary (or flow) conditions will not affect to the solute transport simulations. Density dependent flow simulations may not be compatible with this feature.

  2. ‘Trace particle’ command has been added to perform particle tracking in a steady-state flow field and its input format is following as (or a grok example can be downloaded from HERE):

    • trace particle

    • particle release time

    • maximum trace time

    • maximum trace count

    • initial particle location from file

    • output times for particle locations

    • maximum trace output

  3. Minor bug fixed: when an 1D channel outlet is linked to another domain (e.g., pm and olf) for the boundary condition linking scheme, the maximum flow in the 1D channel is less than the 1D channel dimension (width x incision depth).

HGS Premium November 2018 (Revision 1976 for Windows/1977 for Linux) 

  1. HSPLOT can now process HGS output files up to 2400 units.

HGS Premium October 2018 (Revision 1972 for Windows/1973 for Linux) 

  1. 'choose nodes boundary sheet' has been updated for working with a subsurface domain without using overland flow domain information. Grok input format is the same as previous one (see July 2018 update #2)

  2. Tunnel boundary condition has been added. Boundary condition type is ‘tunnel’. A segment set is required for the ‘tunnel’ boundary condition. In the time value input table, three values (time on, wall pressure, and radius) are needed. Additionally, there are several optional instructions for specifying the physical conditions of a tunnel such as ‘tunnel edz thickness and conductivity’ and ‘tunnel grout thickness and conductivity’. An example of the ‘tunnel’ boundary condition can be downloaded from HERE.

HGS Premium September 2018 (Revision 1965 for Windows/1966 for Linux) 

  1. Reading a third-party numerical domain has been more flexible (e.g., layer or nodal information is not required).

  2. ArcGIS reader has been compatible for linux compilations (e.g., any shp files can be processed by grok compiled using a ifort or gfotran compiler).

  3. Minor bug fixed: check flow solution part for improving computational efficiency.

HGS Premium August 2018 (Revision 1957 for Windows/1959 for Linux) 

  1. Modifications for reading initial heads for dual, overland, and fractures and splitting triangular prisms based on Dompierre et al. (1999).

  2. Minor bug fixes: map k from regional model and run time errors (gfortran).

  3. 'nonlinear bulk thermal conductivity relation' has been added: a new function to compute thermal conductivity as a function of saturation.

    • nonlinear bulk thermal conductivity relation

    • thermal conductivity of air

    • specific heat capacity of air

    • density of air

HGS Premium July 2018 (Revision 1942 for Windows/1943 for Linux) 

  1. Regional model - et zone mapping added:

    • use domain type

    • et

    • Regional model

    • location of regional model prefix (e.g., ../Reference/regionalmodel)

    • map zone numbers from regional model

  2. 'Choose nodes boundary sheet' command added. This command requires bottom and top sheet numbers for selecting boundary nodes for the 3D subsurface (PM) domain. It is similar to 'Choose nodes top boundary' for the surface (OLF) domain:

    • Choose nodes boundary sheet

    • bottom_sheet_# Top_sheet_#

  3. Output precision for some variables has been increased from 9 to 10 digits below the decimal point with eliminating leading zero in a number.

  4. Processing efficiency for updating a regional model properties has been improved using a regional output file (i.e., prefixo.RegionalModelOutput).

  5. Minor bug fixed: regional mapping for the surface domain.

HGS Premium June 2018 (Revision 1932 for Windows/1933 for Linux) 

  1. Bugs related to computational efficiency (Jacobian matrix assembly) have been fixed.

HGS Premium May 2018 (Revision 1916 for Windows/1917 for Linux) 

  1. Regional model - K mapping for selected elements + brick elements (Multiple regional models can be used for mapping K values)

  2. New water balance feature 'fluid mass balance for olf areas using shp file' added for estimating water balance in areas (surface and subsurface domains) selected by users.

  • fluid mass balance for olf areas using shp file
    your ArcGIS shp file name
    # !area number

HGS Premium April 2018 (Revision 1910 for Windows/1912 for Linux) 

  1. New boundary condition link for 'flux nodal by pressure' added. The boundary condition link format is the same as the previous one.

  2. New water balance feature 'compute water volume by area using shp file' added for estimating water volume in certain areas (surface and subsurface domains) selected by users.

  • compute water volume by area using shp file
    your ArcGIS shp file name
    # !area number

     3. 'make olf zone inactive' command added for efficient computing.

HGS Premium March 2018 (Revision 1902 for Windows/1903 for Linux) 

  1. New boundary type 'flux nodal by pressure' added. With this boundary condition, nodal flux is calculated from the nodal pressure (or water depth) at the node. Requires 'pressure-discharge power rating' or 'pressure-discharge table' input instructions to be included inside the 'boundary condition ... end' blocks.

  • For the power rating curve case, nodal flux is calculated based on the equation Q=C*(depth-a)**alpha. Thus, the instruction needs to be followed by three numbers as

pressure-discharge power rating
-300.    ! C (negative as water needs to flow out)
0.01     ! a (minimum depth for water flow)
1.0       ! alpha (exponent)

  • For the stage-discharge table, a series of paired numbers (depth-Q) need to be provided in the following format:

pressure-discharge table
0.01   0.0
0.05  -0.01  
0.1    -0.1
0.5    -1.0

HGS Premium February 2018 (Revision 1898 for Windows/1899 for Linux) 

  1. 'plot pm zone isopach structure' instruction can be added in prefix.plot.control. With this instruction, hsplot will generate isopach thickness and top elevations of each porous medium zone.

  2. Two new properties for the 1D channel media can be defined in cprops files: 'incision depth' and 'weir constant'. Both instructions need to be followed by a floating point number in the next line.
    The elevations of the channel nodes are lowered by the incision depth in each zone to compute the exchange flux between the channel and 2D/3D (overland and porous) media. For the use of the weir constant, see the user manual.

  3. Depth change in the channel media is now considered for time stepping and Newton iterations.

  4. Minor bug fix for third-type transport boundary conditions.

HGS Premium January 2018 (Revision 1885 for Windows/1886 for Linux) 

  1. 'k reduction by impedance factor for chosen elements' command added.
    Requires to read
    Line 1: impedance factor
    Line 2: npanel
    Line 3 - 3+npanel: ton toff
    Hydraulic conductivity is modified for chosen elements such that Knew = K*10**(-impedance*sat at ton) when ton<t<=toff. Impedance factor represents the maximum K-reduction in log-scale during the freezing season.

  2. 'choose elements intersected by raster surface' command added.
    Requires to read the raster file name in the next line.
    Designed to generate a thin continuous material layer for the existing mesh.

HGS Premium December 2017 (Revision 1873 for Windows/1874 for Linux) 

  1. 'scaling factor by raster' command added. This command is similar to 'scaling factor' in the boundary condition command but instead of a single value applies the values given in the raster file. Requires to read the raster file name in the next line.

  2. 'elevation temperature relation' command added for the 'rain and snowmelt' boundary condition. With this command, temperature is calculated as a linear function of the elevation as T(z)=(z-z0)*A+T0. Requires to read z0 and A in the next line together for given T0 in the 'time value table' or 'time raster table'.

  3. 'no flow from channel to olf' command added to force water to flow only from the 2D overland to 1D channel domains (conductance is set to be zero when head is higher in the channel).

HGS Premium November 2017 (Revision 1866 for Windows/1867 for Linux) 

  1. Specified head nodes are now excluded for maximum depth change calculation for overland flow.

  2. New boundary type 'makeup water' added. It is similar to the simple drain but water is introduced into the system for the node set chosen. Q=-C/L(h-href) when h<href; Q=0 when h>href.

  3. New boundary type for density-driven flow and transport 'head vertical static' added. Given head values are applied to the top nodes among vertically aligned set of nodes and for the rest of nodes, head values are calculated to satisfy the vertical hydrostatic condition.

  4. 'fracture distribution coefficient' and 'zoned fracture distribution coefficient' commands are added to define the solute sorption property. Either Kd or retardation factor (fracture retardation factor) can now be used.

  5. 'distribution coefficient scaling by concentration' command added to define the sorption property of a solute as a function of concentration of another species. Requires to read a species number (next line) and the number of data pairs (another line) to define Kd_i=Kd_i(C_j), followed by the list of [C_j,Kd_i].

  6. HSPLOT can now be instructed to process only the selected layers for porous media by including 'truncate pm domain by layer'. This instruction needs to be followed by the following three lines: Line 1 (minimum x coordinate, maximum x coordinate), Line 2 (minimum and maximum y coordinates), Line 3 (minimum and maximum layer numbers to process).

  7. Bug fix for (1) the use of elemental K values in integrated simulations, (2) 'initial concentration from file' for the dual domain when it is assigned only for a portion of the entire domain, and (3) canopy evaporation calculation.

HGS Premium October 2017 (Revision 1841 for Windows/1842 for Linux) 

  1. Slow-down issues with the interception/canopy evaporation improved now

  2. New boundary type 'reservoir' added. A single overland node is assumed to be connected to a reservoir with minimum and maximum storage capacity with intended inflow/outflow schedule. Manual will be updated accordingly.

  3. 'k scaling factor' command added. Hydraulic conductivity can be scaled for a single zone by the factor specified in the mprops file or for multiple zones in the grok file. Manual to be updated accordingly.

  4. Target times updated now from the commands for time varying roughness and time dependent k. HGS now outputs time-dependent elemental K values for hsplot to process for visualization

HGS Premium September 2017 (Revision 1827 for Windows/1828 for Linux) 

  1. Minor bug fix: initial condition for 1D channel medium

  2. 'time dependent k for chosen elements' and 'time dependent variable k for chosen elements' commands were added (reference manual will soon be updated accordingly ). The 'time dependent k for chosen elements' command is required to read

    • the number of time panels (integer) - npanel

    • time(1), Kx(1), Ky(1), Kz(1)

    • time(2), Kx(2), Ky(2), Kz(2)

    • ...

    • time(npanel), Kx(npanel), Ky(npanel), Kz(npanel)

  3. For the 'time dependent variable k for chosen elements' command,

    • the number of time panels (integer) - npanel

    • time(1), filename(1)

    • time(2), filename(2)

    • ...

    • time(npanel), filename(npanel);

    • where the files filename(i) need to include the same number of lines as the number of chosen elements (nelem) as

    • Kx(i,1), Ky(i,1), Kz(i,1)

    • Kx(i,2). Ky(i,2), Kz(i,2)

    • ...

    • Kx(i,nelem), Ky(i,nelem), Kz(i,nelem)

  4. Print-out for the large integer numbers in the prefixo.eco and prefixo.lst files is improved.

HGS Premium August-2 2017 (Revision 1820 for Windows/1821 for Linux) 

  1. Bug fix for observation point/well tecplot output files

  2. Hydrograph tecplot output now includes 1D channel flow

HGS Premium August 2017 (Revision 1815 for Windows/1817 for Linux) 

  1. 'K to tecplot' works for full tensor K and HSPLOT processes full-tensor elemental K values

  2. Observation points/wells output files now include pressure head as well as total head. Zone title is assigned also for a observation point.

  3. Unnecessary debug print out for channel segments generation is now removed.

  4. Subsurface evaporation is now limited by surface evaporation: EVP_olf = alpha_olf*(1-f1)(PET-CAN); EVP_pm = alpha_pm*(1-f1)(PET-CAN)*EDF has been modified as EVP_pm = alpha_pm*(1-f1)*(PET-CAN)*(1-alpha_olf)*EDF.

  5. 'read 3d grid, ascii' has been improved for tetrahedral mesh and can be tested with 'mesh to tecplot'

  6. Bug fix for fluid mass balance output when the channel domain is used.

  7. Updates for reference manual (time varying friction...end)

HGS Premium July 2017 (Revision 1798 for Windows/1799 for Linux) 

  1. HSPLOT: Comparison to observation head values for given x, y, z locations (read_obs_heads_xyz)

  2. HSPLOT: 'Simulation time unit conversion factor' for the output time unit conversion

  3. Bug fix for the following:

    • 'Time varying friction' when the number of time panels are larger than 2

    • hsplot: paraview output formats

  4. 'Choose faces top block, enter of mass' command added. 'Choose faces top block' command chooses the faces when all the nodes composing the faces are within the block and this command chooses the faces when the center of the faces are located within the block.

  5. 'Dual freezing by pm temperature' option added for freezing/thawing with dual media. Manual will be updated accordingly soon.

HGS Premium June 2017 (Revision 1790 for Windows/1791 for Linux) 

  1. For integrated surface and subsurface simulations, HGS now outputs RAIN and PET distributions for the overland domain, so users can see their spatial distributions using tecplot.

  2. Removed the node count limitation in hsplot. Now HSPLOT can process more 10M nodes.

  3. 'choose faces vertical from polyline' command added. Manual will be updated soon accordingly.

  4. For dual continuum simulations, HGS now outputs the fluid and mass exchange between primary and secondary media.

  5. 'Time varying friction' can be used to define Manning's coefficient as a function of time in oprops file. Manual will be updated soon to reflect the change.

  6. Minor bug fixes for 'compare depth to gw table' (HSPLOT), 'no freezing in dual domain', multiple use of the 'regional model' command, 'simple river' boundary conditions.

A bug was noticed in the May release for velocity calculation in saturated flow. All users are recommended to update to the June release right away.

HGS Premium April 2017 (Revision 1743 for Windows/1744 for Linux) 

  1. 'Output ET details' command added. With this instruction in grok, HGS prints out ET details (PET, total AET, transpiration, evaporation, etc) for each PET boundary in ET_Detailed_Info_bcname.dat.

  2. For water balance output, HGS now reports canopy evaporation as part of evapotranspiration (HGS was reporting effective precipitation for the rain boundary as precipitation minus canopy interception). Both in prefixo.lst and prefixo.water_balance.dat, HGS now reports PET as a reference to AET.

  3. 'DDF Picard iteration control' command added. This instruction requires to read an integer number in the following line as the maximum allowed number of iterations for Picard solution in density-dependent flow and transport simulations to decide the time step size in the next time step. The debug.control file now includes Picard convergence criteria, maximum number of iterations, maximum allowed number of iterations to be modified during density-driven flow and transport simulations.

  4. 'Soil frost K by ratio' command added. This instruction is similar to the 'Soil frost K' command but specifies the ratio of soil frost K to the original K.

  5. Minor bug fixes (Compute water volume by zone/Cutoff wall with rain/snow boundary conditions) and manual updates

HGS Premium March 2017 (Revision 1729 for Windows/1730 for Linux)

  1. A "Quick Start Guide" section is added in the manual to get users up to speed quickly on the basic operation of the HGS model.

  2. 'Regional model' command added. This command can located in the grid definition section after users define a 2D mesh or after the entire 3D mesh is defined. This can be used together with 'initial head from regional output file', 'map zone numbers from regional model', and 'elevation from regional model gb file'. 'initial head from regional output file' command does not require to read the regional model prefix now.

  3. 'Map zone numbers from regional model' command added. This command can be used after a regional model is defined for the porous medium or overland domains to map zonation used in the regional model to the local model.

  4. 'Elevation from regional model gb file' command added. This command can be used to define the elevation from the regional model gb file after a regional model is defined.

  5. 'Compute water volume by zone' command added. With this command in grok, HGS reports the amount of water stored in each of porous medium or overland zones at each simulation time in prefixo.water_volume_pm_zone.dat and prefixo.water_volume_olf_zone.dat.

HGS Premium February 2017 (Revision 1720 for Windows/1719 for Linux)

  1. 'Auto save on' command added. This command requires to read a time interval in seconds in the next line. Restart files for head and concentration will be generated/updated with the interval in prefixo_head.asv and prefixo_conc.asv. This command is designed to help the cases when the equilibrium simulations takes long and only the final results are important. ASV files are formatted in the exactly same way as the HEN and CEN files to be used as restart files. Last time when the files are updated can be found in prefixo.lst file (search for 'auto save at').

  2. 'Minimum relaxation factor for convergence' command added. When the 'compute underrelaxation factor' command is used, convergence will be declared when the relaxation factor is larger than the value specified. Previously it was 0.95 and now users can adjust this minimum.

  3. A potential data race condition for HGS parallel implementation was identified and fixed.

  4. Manual update for 'Newton minimum iterations' (default - 0). Newton solver will declare the convergence only when the iteration count is larger than the minimum specified.

HGS Premium January 2017 (Revision 1709 for Windows/1710 for Linux)

  1. Improvement for 'Map rectangular fractures from tecplot file' using a structured auxiliary mesh (SAM) search algorithm

  2. Improvement for 'Porosity to tecplot'

  3. Manual updates for the following commands:

    • 'k to tecplot'

    • 'nodal flux reduction by pressure head'

HGS Premium December 2016 (Revision 1702 for Windows/1703 for Linux)

  1. Minor bug fixes for 'zones from arcview for chosen elements' and 'initial head from regional output file')

  2. Following commands were cleaned/added in the manual:

    • 'choose faces top gb common' to choose the faces tagged in two gb echos files

    • 'choose faces top gb exclude' to choose the faces tagged in the first gb echos file excluding the faces tagged in the second gb echos file

    • 'report exchange for olf zones' to report the exchange flux for each of overland zones (prefixo.fluid_exchange_olfz.dat)

    • 'choose nodes between zones' to choose the interface nodes between two zones

    • 'choose nodes by zone' to choose all the nodes within a zone

    • 'make observation well from xy' to create a observation well from the x and y coordinates and bottom and top sheet numbers

    • 'choose segments gb node list' to choose a segment from a set of nodes specified by the 2D node numbers and sheet numbers; designed to help to create horizontal wells/drains

    • 'choose segments xy between sheets' to choose a segment using the x and y coordinates and bottom and top sheet numbers; designed to help to create vertical wells/drains

    • 'function surface elevation initial head' to assign initial head values as a function of ground surface elevation; h(t=0)=z0+(zsurf-z0)*scaling_factor; designed to assign an initial head distribution as subdued topography

HGS Premium November 2016 (Revision 1693 for Windows/1694 for Linux)

  1. 'Choose nodes 2d-list sheet' command added. This instruction requires to read a sheet number and a file name in the next two lines. The file consists of the list of 2d node numbers (one per each line) and the number is converted to a 3d node number based on the sheet number specified. If the 2d node number is larger than nn2d but less than nn, it is automatically converted to a corresponding 2d node number. 'Choose nodes top 2d-list' command works similarly but without a sheet number.

  2. 'Random Kd field from fgen' command added. This instruction works in the same way as 'Random K field from fgen' but given anisopropy ratios will be neglected.

  3. 'Compute statistical properties of plume' command added. This instruction causes HydroGeoSphere to write the statistical properties of solute plume in porous media at each time step (zeroth to 4th moments). Output will be written to a file called prefixo.Statistical Plume Props.dat.

  4. 'Zones from arcview for chosen elements' command improved. If the selected attribute is a character field, it prints out the names without spaces/identify the same names to assign the same zone number.

HGS Premium October 2016 (Revision 1671 for Windows/1672 for Linux)

  1. 'Initial head from regional output file' command added. This command is used to import a flow initial condition for a local model from a regional model simulation result. Requires to read the following parameters in the next two lines: prefix_regional, and 'regional_output_file_name'. Designed for telescopic simulations (coarse regional and refined local models).

  2. 'concentration control, multi-species' command added. For multi-species transport simulations, HGS now calculate/print-out the maximum concentration change for each species. This command will apply different values for maximum concentration change allowed for different species (an example is included in verification/pm_cd as commented out by !AQT). With this implementation, 'concentration control' or 'concentration control, multi-species' commands need to show up after all the species are defined (solute ...end), otherwise grok will issue a warning and stop.

  3. 'pet from crop coefficients' command added to be included in etprops files (for each zone) (see verification/panday/panday.etprops as commented out by !AQT). The command is designed to partition PET into PE and PT such that PT = (PETo-Ec)*BCC; PE = (PETo-Ec)*(MCC-BCC) where Ec is the canopy evaporation, and MCC and BCC are the maximum crop coefficient & basal crop coefficient, respectively. Users can include the following time series for each ET zone to provide MCC(t) and BCC(t):
    'maximum crop coefficient table ...end'
    'basal crop coefficient table ...end'
    With this command, C1 and C2 parameters and LAI (f1 function) will not be used for the PET partitioning calculation. When BCC = C1*LAI+C2 and MCC=1, the results should be the same as before. Note that f1 has an upper limit of 1.0 but MCC could be larger than 1.0 as PETo is considered to be 'reference evapotranspiration', not 'potential evapotranspiration' (see FAO 56 guideline document for details). Note also that LAI will still be used for canopy evaporation calculation.

  4. Now Aqaunty can provide a floating license to the users for both Windows and Linux (HGS Linux is now fully integrated with the RLM). The floating license is designed to acquire the HGS license in any machine through internet (each account will have a limit for the number of concurrent HGS executions). Any interested users can contact the Aquanty Support Team. The existing Linux HGS users will need to generate hostid.txt in their systems using rlmhost.sh (included in the zip file) and can ask a new license file.

HGS Premium September 2016 (Revision 1649)

  1. 'refine 2d grid' command added. After importing 2d triangular grid, this command causes grok to refine one triangle to 4 triangles. This can be repeated until a desired resolution is achieved. The number of nodes increases about 4 times with this command. This command is designed to best perform when the elevation is defined by high-resolution raster files.

  2. 'reduce 2d grid, boundary file' command added. This command causes grok to exclude the triangular elements outside a polygon (any of its vertices) and to re-number the nodes and elements within the polygon. Requires a file name for a text ascii file which defines the polygon with x- and y-coordinates in each line - first and last points need to be identical for a closed polygon. Combined with the 'refine 2d grid' command, this can provide a basis for telescopic mesh refinement.

  3. Updates for the manual.

  4. Updated license manager (RLM - V.12.1) for cloud license. Aquanty team has planned to implement a floating license scheme for HGS to provide users more flexibility in various computing environments. This should not influence the exisitng node-locked license.

HGS Premium August 2016 (Revision 1640)

  1. A new boundary condition command 'scaling factor' was added (to be used within 'boundary condition ... end'). This command requires a floating point number in the next line. All the flux and head values specified by 'time value table', 'time raster table', etc will be multiplied by the scaling factor before being used. For example, when a time series of spatially varying precipitation pattern is specified in the 'rain' boundary condition using 'time raster table' and users want to uniformly scale down the values, to say, 50%, then 0.5 scaling factor can be specified.

  2. For soil water freezing/thawing simulations, HGS now outputs depth-temperature-ice/total water ratio data for specified output times in the prefixo.temperature_profile.dat tecplot file. When users try to run this version for the existing inputs, it is recommended to delete the existing 'prefixo.output_variable.control' file. An example output file for abdul_snowmelt verification problem (abdul_snowmelto.temperature_profile.dat)

  3. 'Initial head from porous medium' command now works for any domains (e.g., dual well/tile/fracture medium).

  4. Third Linux beta release with a temporary license file (valid until mid-September). Aquanty team keeps working on to make it more stable.

HGS Premium July 2016 (Revision 1631)

  1. In fluid balance output files (prefixo.water_balance.dat), HGS prints out only fluid balance information for only first 99 boundary conditions if there exist more than 99 boundary conditions. This restriction was applied to prevent HGS crash for creating excessive number of columns.

  2. Further clean-up for grok.dbg print-out for ET simulations.

  3. A second beta version for HGS Linux is now available to download. It now requires users to create an environment variable HGSDIR and keep the license file in that specific directory. In the case of bash, users can add the following two lines at the end of .bash_profile and copy all the executables and license file in the specified directory /home/username/HGSLinux (Note that slightly different syntax is required for different shells used):

    1. export HGSDIR=/home/username/HGSLinux


  4. Minor bug fixes and manual updates (offset base; elevation from file; initial head from xyh file; initial concentration from xyc file; z function initial concentration; specified concentration from initial concentration; specified third-type flushing).

HGS Premium June 2016 (Revision 1620)

  1. With the 'flow solver maximum iterations' and 'transport solver maximum iterations' commands, the maximum number of solver iterations are not bounded by the number of equations. Problems were identified for which the linear solver could require more iterations than the number of equations with BiCGStab.

  2. 'remove negative coefficients' command is effective for saturated flow and transport now. Users still need to be cautious in using the command if there are many negative inter-nodal conductance. It can significantly improve the numerical efficiency for saturated flow and transport only with limited number of negative coefficients.

  3. Minor bug fixes: boundary condition linking with 1D structures and critical depth BC; large grok.dbg file size for ET simulations.

HGS Premium May 2016

  1. 'transpiration limiting pressure head' and 'evaporation limiting pressure head' commands added. These can be used as alternatives for 'transpiration limiting saturations' and 'evaporation limiting saturations' commands.

  2. 'elevation from file' command added. The command works with 'base elevation' and 'new layer' within 'generate layers interactive' and requires an ascii file that contains nn2d (number of nodes in each sheet) number of elevation data (one per each line). Users can edit/modify/generate the elevation data to feed HGS in an ascii format.

  3. 'initial head from xyh file' and 'initial concentration xyc file' commands added. These commands require the maximum distance and the name of the file (each per line) which contains the number of data (nxyh) followed by nxyh sets of (x,y,head) and (x,y,conc) data. Any selected node will take a value from the closest point data if the distance between two are smaller than the maximum distance. The purpose of these commands are to provide a tool to incorporate the measurements into the initial conditions.

  4. 'z function initial concentration' command added. The command requires to read the next two lines with (z1, c1(z1),c2(z2), ...) and (z2,c1(z2),,c2(z2), ...) data. For chosen nodes, grok interpolates the concentration of a node based on its elevation.

  5. 'specified concentration from initial concentration' command added. The command forces a set of chosen nodes to be specified concentration nodes and the values are taken from the initial concentration.

HGS Premium April 2016

  1. HGS Linux (beta) is now available to download with a time-locked license - compiled with the Intel Fortran with the static library option. The license will support up to 10 mac addresses within a single box. The zip file includes three HGS executables (grok.x/hgs.x/hsplot.x), a mac address extractor (mac.x), and a temporary license which is valid until June 1, 2016 for any machine. A new version will become available every three months. The maintenance schedule may be adjusted, depending on the demand.

  2. Boundary Condition Link (BCL) between 1D, 2D, and 3D domains has been updated. Such grok commands as 'choose nodes gb node list', 'choose nodes gb wall node list', 'create node set for cutoff wall', and 'choose node number for cutoff wall' have been updated for this purpose. Manual will soon be updated accordingly.

  3. 'specified third-type flushing' command added - requires to read [npanel; q(i),i=1,npanel]. This new transport boundary condition is applied to a set of no flow faces, to simulate the flushing as total mass flux = -qAC.

  4. [read "properties" from raster] commands have been improved to remove the possibility of reading a value not from the cell which the center of an element belongs to, but from its neighbor cells.

HGS Premium March 2016

  1. Default values for canopy interception parameter and initial interception storage set as 1.5 mm (based on Rowe, L.K. 1983. Rainfall interception by an evergreen beech forest, Nelson, New Zealand. Journal of Hydrology, 66: 143-158.)

  2. Minor bug fixes and manual updates

HGS Premium February 2016

  1. Improvement for simultaneous overland and fracture transport

  2. Grok will issue a warning and stop when a PET boundary condition is applied without defining ET zones/properties

  3. Some minor bug fixes and manual updates

HGS Premium January 2016

  1. For dual continuum transport simulations, HGS now outputs the mass exchange flux between porous medium and dual continuum in raw mass balance output file.

  2. Improvement for freezing/thawing analytic integration - being further improved.

  3. Improvement for 'flux nodal' boundary condition for saturated flow.

HGS Premium December 2015

  1. 'flux nodal' boundary condition can have an option to reduce flux when the pressure head at the node becomes lower than a certain value. 'nodal flux reduction by pressure head' instruction can be included in 'boundary condition ... end' and it requires two pressure head values in the next line to read ph1 and ph2. If ph>ph2, specified nodal flux is applied; if ph<ph1, flux becomes zero; if ph1<ph<ph2, flux gradually increases between 0 and the specified value following a function x sup 2(1-x) where x=(ph-ph1)/(ph2-ph1). This is supposed to help prevent slowdown of the model due to over-pumping. Manual will be updated later.

  2. Evaporation calculation can follow either Eq.2.80 or Eq.2.81 in the user manual. By default, potential evaporation is calculated as (PET-canopy evaporation)*(1-f1) (Eq.2.81) and optionally (PET-canopy evaporation-transpiration) (Eq.2.80) - Users can include 'potential evaporation using transpiration' in grok for this. Manual will be updated accordingly.

  3. 'tracing contaminant source' is added to improve backward-in-time transport simulation capability in the overland domain. Needs for further improvement have been identified.

  4. 'target times ... end' command working properly. With this command, time stepping will be adjusted to hit the specified target times. This improvement has been identified to be potentially very useful for HGS-PEST coupling and other purposes when the simulation results need to be compared to the measured at specific times.

  5. 'soil water balance' will be reporting the amount of water in the overland domain and below and subsurface above water table. It also reports the amount of water in the top 10cm and 1m.

HGS Premium November 2015

  1. 'read overland zones from raster, dominant class' is added to assign a dominant land use class for each of surface triangular elements. - 'read overland zones from raster' assigns the zone number from the raster value at the center of the elements. This new command can be most useful when the resolution of the raster file is much higher than the grid resolution.

  2. 'generate uniform rectangles' can now specify the origin of the 2D mesh (optional). For this command, required data format is: [x,nx,(x0); y,ny,(y0)] where x0 and y0 are the coordinates of the origin.

  3. 'truncate time domain' instruction for hsplot has been fixed. Users can force hsplot to process the outputs between two times (example).

HGS Premium October 2015

  1. For the grok commands to read ascii raster files, coordinates for the lower left corner are assumed to represent the lower left corner of the lower left cell (it was assumed that they are for the center of the lower left cell) - diagram

  2. For 'read zones from raster for chosen elements' and 'read overland zones from raster' commands, grok does not (bi-linear) interpolate the values to assign; head and elevation will still be interpolated

  3. Zero canopy evaporation is forced when LAI is smaller than 10E-8. This will be clarified in the manual.

  4. Third-type transport boundary conditions implemented for discrete fracture simulations (example).

  5. Further breakdown for mass crossing slice (advective and dispersive) from the 'slice flux output nodes from chosen' command

HGS Premium September 2015

  1. 'read elemental k from file' can now read one (isotropic), three (anisotropic), and six (full tensor) values for each element; hsplot will process them accordingly (example)

  2. debug control instruction 'write seepage face output to .lst file' fixed to work with 'seepage node' BC

  3. potential negative initial time step due to non-zero 'initial time' and input time series fixed (example)

  4. 'slice flux output nodes from chosen' reports further breakdowns for transport (advective and dispersive mass flux crossing slice along different media)

  5. HGS utility available to convert FEFLOW mesh (.fem) and AlgoMesh into HGS inputs (link to download)

  6. Bug Report Form to download

HGS Premium August 2015

  1. Case-sensitivity for 'end' and 'include' fixed (example)

  2. Third-type transport BC from file fixed (example)

  3. Transport mass balance and slice flux output nodes fixed (example)

  4. Precision for for 'compute velocity field from head' improved

  5. Random fracture networks improved (example output)

  6. Permafrost simulation capability improved for fracture zones

  7. HGS manual split into user manual & reference manual (input instructions)

HGS Premium July 2015

  1. "Fracture zone porosity" [fprops] command added - works together with "High-k zone" (example)

  2. "Zoned fracture retardation factor" and "Fracture retardation factor" [solute] fixed (example)

  3. The issue associated with hidden tabs in blank lines fixed (example)

  4. Time varying root depth and logistic root growth function implemented for evapotranspiration [etprops] - manual will be updated accordingly

  5. "K to tecplot" command fixed - to convert zoned k to elemental k & to create prefixo.ElemK_pm(dual).0001 for hsplot to process (example)