Dye Regions

Dye regions are used for fluid motion tracking and are in that sense analogous to the well known experimental method of flow visualization.

It is possible to define an arbitrary number of dye regions in a simulation with the same or different color. As a fluid particle (irrespectable of its phase definition/density) passes through a given dye region, it will get assigned a specified “color” (integer, scalar property which is then output in the particle data). Usage of dye regions eliminates the need of using multiple FLUID phase definitions in order to track the fluid flow from a specific location and are therefore more computationally efficient. Dye regions can only be spherical in shape. If a particle passes through multiple dye regions, it will adopt the color of the last dye region through which it passed.

dyeRegions
{
    dyeRegion
    {
        dyeregion_clr           1                           
        dyeregion_cntr          "0.0 0.1 0.2"               
        dyeregion_rad           0.1                         
        dyeregion_radodx        2.5                         
        dyeregion_tstart        0.0                         
        dyeregion_tend          1.0                         
    }
}

dyeregion_clr: Color assigned to the dye region.
dyeregion_cntr: Center coordinates of the dye region sphere.
dyeregion_rad: Radius of the dye region sphere. Unit: [m]
dyeregion_radodx: Radius of the dye region sphere as a function of dx (for example, when specified 3.0, implies 3.0*dx).; If both dyeregion_rad and dyeregion_radodx are present, the latter takes precedence.
dyeregion_tstart: Start time of dye injection.
dyeregion_tend: End time of dye injection.