# Reports

MFIX-Exa provides several options for reporting data from the solver.

## Particle size distribution

The particle size distribution (PSD) can be reported for different regions in the model. This feature requires a region already defined in the regions inputs, and only volume regions are valid for PSD reports. Each report must be associated with a single region; combining multiple regions in one report is not supported.

The following inputs are defined using the prefix `mfix.reports`:

| Description | Type | Default
--- | --- | --- | ---
diameter | Names of the PSD reports | Strings | None

The following inputs are defined using the prefix `mfix.reports.diameter.[report_name]`:

| Description | Type | Default
--- | --- | --- | ---
region | Region to compute the size distribution | String | None
int | Number of time steps between report outputs. Cannot be used with `per_approx`. | Int | None
per_approx | Simulation time (in seconds) between report outputs. Cannot be used with `int`. | Real | None
bins | Number of bins in PSD discretization | Int | None
min | Minimum particle size included in discretized PSD | Real | None
max | Maximum particle size included in discretized PSD | Real | None

A sample inputs snippet for outputting the particle size distribution is given below. Two regions are created that span the left and right sides of the domain, and used to create two reports. The `left-side` report is a PSD consisting of 32 bins between 30-3000 microns that is output every 50 time steps. The `right-side` report is a PSD consisting of 64 bins between 30-3000 microns that is output every 0.5 seconds of modeled time.

Listing 10 Snippet of inputs for particle size distribution reports.

    # Define two regions for collecting report data
    # -------------------------------------------------------------
    mfix.regions = ... left right

    regions.left.lo  = 0.00  0.00  0.00
    regions.left.hi  = 0.05  0.10  0.10

    regions.right.lo  = 0.05  0.00  0.00
    regions.right.hi  = 0.10  0.10  0.10

    # Define two particle size distribution reports
    # -------------------------------------------------------------
    mfix.reports.diameter = left-side  right-side

    mfix.reports.diameter.left-side.region  = left

    mfix.reports.diameter.left-side.int  =    50
    mfix.reports.diameter.left-side.bins =    32
    mfix.reports.diameter.left-side.min  =    30.0e-6
    mfix.reports.diameter.left-side.max  =  3000.0e-6

    mfix.reports.diameter.right-side.region  = right

    mfix.reports.diameter.right-side.per_approx =  0.5
    mfix.reports.diameter.right-side.bins =       64
    mfix.reports.diameter.right-side.min  =       30.0e-6
    mfix.reports.diameter.right-side.max  =     3000.0e-6