# Plotfiles and Other Output

The following inputs must be preceded by “mfix.” and control frequency and naming of plotfile generation as well as whether the EB geometry or level set should be written out, and if the particles should be written out in Ascii format (for debugging).

| Description | Type | Default
--- | --- | --- | ---
plot_int | Frequency of plotfile output; if -1 then no plotfiles will be written at this frequency | Int | -1
plot_per_approx | Time period of plotfile output (approximate); does not modify dt if -1 then no plotfiles will be written at this frequency | Real | -1
plotfile_on_restart | Should we write a plotfile when we restart (only used if plot_int>0) | Bool | False
plot_file | Prefix to use for plotfile output | String | plt
par_ascii_file | Prefix to use for ascii particle output | String | par
par_ascii_int | Frequency of ascii particle output; if -1 then no particle ascii files will be written | Int | -1
par_ascii_per_approx | Time period of the ascii particle output (approximate); if -1 then particle ascii files will not be written at this frequency | Real | -1
file_digits | Number of digits to use in plotfile (plt[0-9]+) and checkpoint (chk[0-9]+) filenames. | Int | 5
ascent_int | Frequency of ascent pipeline; if -1 then ascent will not be called. | Int | -1
ascent_per_approx | Time period of the ascent pipeline (approximate); if -1 then ascent will not be called. | Real | -1

The following inputs must be preceded by “mfix.” and control what variables will be written in plotfiles.

| Description | Type | Default
--- | --- | --- | ---
plt_regtest | Save all variables to plot file (overrides all other IO flags) | Int | 0
plt_vel_g | Save fluid velocity data to plot file | Int | 1
plt_ep_g | Save fluid volume fraction to plot file | Int | 1
plt_p_g | Save fluid pressure to plot file | Int | 0
plt_ro_g | Save fluid density to plot file | Int | 0
plt_mu_g | Save fluid molecular viscosity to plot file | Int | 0
plt_diveu | Save div(ep_g . u) to plot file | Int | 0
plt_volfrac | Save Eulerian grid volume fraction (from cut cells) to plot file | Int | 0
plt_gradp_g | Save gradient of pressure filed to plot file | Int | 0
plt_vort | Save vorticity to plot file | Int | 0
plt_vel_p | Save particle velocity to plot file | Int | 1
plt_radius | Save particle radius to plot file | Int | 0
plt_volume | Save particle volume to plot file | Int | 0
plt_volume | Save particle volume to plot file | Int | 0
plt_mass | Save particle mass to plot file | Int | 0
plt_ro_p | Save particle density to plot file | Int | 0
plt_omoi | Save (one divided by the) particle momentum of inertia to plot file | Int | 0
plt_mass | Save particle mass to plot file | Int | 0
plt_omega_p | Save particle angular velocity to plot file | Int | 0
plt_drag_p | Save particle drag force to plot file | Int | 0
plt_phase | Save particle type to plot file | Int | 0

The following inputs must be preceded by “mfix.” and control whether the EB geometry or level set should be written out.

| Description | Type | Default
--- | --- | --- | ---
write_ls | Should we write a plotfile holding the level set and volfrac? If true, it will only be written once,after initialization or restart | Bool | False
write_eb_surface | Should we write out the EB geometry in vtp format If true, it will only be written once,after initialization or restart | Bool | False
plt_geom | Should we write a plotfile holding the EB geometry data? If true, it will only be written once,after initialization or restart | Bool | False

Ascent has been integrated into MFIX-Exa for in situ visualization. For codes that have been built with Ascent support, the following inputs must be preceded by “ascent.” and specifies the ascent actions for fluid and/or particles. The frequency which these are called is controlled by ascent_int or ascent_per_approx, see above. Note that if an ascent pipeline is being included in a GPU build/run, then you must enable managed memory, i.e., set amrex.the_arena_is_managed = true.

| Description | Type | Default
--- | --- | --- | ---
actions | yaml file of the ascent actions (ex. ascent_actions.yaml). If no file name is provided, then calls to Ascent are skipped. | String |

The following inputs must be preceded by “mfix.solids.” and allow to write additional plotfiles which contain only solids variables in specific regions at fixed timesteps or approximated simulation times. All these parameters are user-defined.

| Description | Type | Default
--- | --- | --- | ---
regions | Specify regions that will be used for plotfiles | String |
[region] | Specify which solids phases will be plotted | String |
[region].plot_int | Specify timestep frequency for plotting the file | Int | 0
[region].plot_per_approx | Specify time interval frequency for plotting the file | Real | 0
[region].plt_regtest | Save all variables to plot file (overrides all other IO flags) | Int | 0
[region].plt_radius | Save particle radius to plot file | Int | 0
[region].plt_volume | Save particle volume to plot file | Int | 0
[region].plt_mass | Save particle mass to plot file | Int | 0
[region].plt_ro_p | Save particle density to plot file | Int | 0
[region].plt_omoi | Save inverse of particle momentum of inertia to plot file | Int | 0
[region].plt_vel_p | Save particle velocity to plot file | Int | 0
[region].plt_omega_p | Save particle angular velocity to plot file | Int | 0
[region].plt_statwt | Save particle statistical weight to plot file | Int | 0
[region].plt_drag_p | Save particle drag force to plot file | Int | 0
[region].plt_cp_s | Save particle specific heat coefficient to plot file | Int | 0
[region].plt_T_p | Save particle temperature to plot file | Int | 0
[region].plt_convection | Save particle convection coefficient to plot file | Int | 0
[region].plt_X_s | Save particle species mass fractions to plot file | Int | 0
[region].plt_vel_s_txfr | Save particle interphase velocity transfer to plot file | Int | 0
[region].plt_h_s_txfr | Save particle interphase enthalpy transfer to plot file | Int | 0
[region].plt_mass_sn_txfr | Save particle interphase mass transfer to plot file | Int | 0
[region].plt_phase | Save particle phase to plot file | Int | 0
[region].plt_state | Save particle state to plot file | Int | 0

For each region with name [region] specified in the inputs, it will be saved a plotfile with name “partsXXXXX_[region]”, where XXXXX stands for the timestep number.

Below is an example for specifying the inputs to plot solids data in a given region.

    mfix.solids.regions = my_region

    mfix.solids.my_region.plot_int = 10
    mfix.solids.my_region.plt_vel_p = 1