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)