HydroGeoSphere/Output

During execution, grok and HydroGeoSphere create many output files, for which a complete list with brief descriptions can be found in Appendix B. Here, we will discuss in more detail the output which is of most interest to the user.

Output files

The main mechanism for generating output from HydroGeoSphere is through the use of the Output times instruction. For each output time defined by the user, there will be a problem-dependent set of output files which will be generated automatically. Here is a partial list of the files which were created by the verification problem described in Section 4.5.2:

f_cdo.head.001
 f_cdo.velocity_darcy.001
 f_cdo.velocity_darcy_fracture.001
 f_cdo.velocity_linear.001
 f_cdo.velocity_linear_fracture.001
 f_cdo.fracture_aperture.001
 f_cdo.concentration.Radium.001
 f_cdo.concentration.Thorium.001
 f_cdo.concentration.Uranium.001
 f_cdo.concentration.Radium.002
 f_cdo.concentration.Thorium.002
 f_cdo.concentration.Uranium.002

As you can see, file names are made up of the problem prefix, in this case f_cd, a descriptor, for example o.concentration.Radium. and a 3-digit number such as 001, which relates the data contained in the file to an output time number. Note that for output time number 001, there are quite a few more output files than for number 002. This is because the flow solution in this case is steady-state, and so it is fully described by one set of output. For timestep 002, only variables which have changed are output, in this case the concentrations of the 3 species in the transport solution. Finally, the set of files which gets generated is problem-dependent, and so certain types of files may or my not appear. For example, since this problem has discrete fractures, we are seeing some fracture velocity and aperture output.

In order to conserve disk space and increase the efficiency of file I/O, these files are all stored in binary format, so they can not be viewed with a standard text editor. However, through the use of the post-processing tool HSPLOT, which is described in Section E, it is possible to create ascii versions of the data contained in these files which are also compatible with the third-party visualization tools TECPLOT and GMS.

Time output format

By default, simulation time is written in listing and output files in a fixed format using the FORTRAN F format descriptor f17.5, which is not suitable for outputting times greater than 999,999 or less than 0.00001. If you prefer to use scientific notation, you can choose it using the instruction:

Time output scientific format

The other option is to use the FORTRAN G format descriptor (i.e. general format) in which a mix of fixed and scientific format is used depending on the magnitude of the output. If you prefer this notation, you can choose it using the instruction:

Time output general format

Since these instructions can be used in the debug.control file (see Section C), it might sometimes be usefult to switch back to fixed format. To do so, use the instruction:

Time output fixed format

Mass balance output format

Similarly, mass balance output can be controlled by the instructions:

Mass balance output scientific format

and

Mass balance output general format

Mass balance output fixed format