Scalar Output Data

Scalar fields are represented as sets of continuous Eulerian fields defined throughout the computational domain. Because these fields exist everywhere in space and evolve in time, M-Star provides multiple mechanisms to extract and visualize them during a simulation. These mechanisms are configured through the Output Panel and associated sampling and output rate settings.

Two primary categories of data are produced: reduced statistical scalar outputs for plotting aggregated scalar quantities over time, and surface and volume spatial visualization outputs for examining how scalar fields vary throughout the domain.

Reduced Statistical Scalar Output

These outputs consist of compact, pre-processed, reduced quantities that are written to text-based statistics files. They include system-level metrics such as total scalar mass or volume, volume-averaged scalar concentration, and the coefficient of variation of concentration throughout the fluid domain. The reduced statistics also capture scalar addition and removal through inlets and outlets, interfacial fluxes across phase boundaries, and changes in total scalar mass arising from chemical reactions or scalar–particle coupling. The Statistics page provides a complete list of the raw and reduced statistical data available for output.

Surface and Volume Outputs

These are geometry-aware datasets that preserve spatial structure. They are written in binary VTK formats  suitable for post-processing in M-Star Post and similar tools.

M-Star supports sampling at two levels:

  • 2D Slice Output: These planes and surfaces constitute a planar cut (or slice) through the domain that returns a spatial field map over an area. This is the most common visualization for examining spatial variations in concentration. These outputs can be produced at specific locations by Output Planes or Output Surfaces to a model.

  • 3D Volume Output: This volume output constitutes full 3D field data for the domain or a specified region. Because of data size, volume output is typically written less frequently or under specified conditions. The extents of this output are automatically defined by the Main Lattice.

Sampling Probes and Sampling Lines

In addition to reduced statistical data (which is computed over the full domain), localized reductions and scalar field interrogation can be performed using sampling probes, sampling lines, control volumes, or global variables with local fluid reductions.