10.12 Postprocessing for MRF and Mixing Plane Problems

When you solve a problem using the multiple reference frame or mixing plane model, you can plot or report both absolute and relative velocities. For all velocity parameters (e.g., Velocity Magnitude and Mach Number), corresponding relative values will be available for postprocessing (e.g., Relative Velocity Magnitude and Relative Mach Number). These variables are contained in the Velocity... category of the variable selection drop-down list that appears in postprocessing dialog boxes. Relative values are also available for postprocessing of total pressure, total temperature, and any other parameters that include a dynamic contribution dependent on the reference frame (e.g., Relative Total Pressure, Relative Total Temperature).

Relative velocities are relative to the translational/rotational velocity of the "reference zone'' (specified in the Reference Values task page). The velocity of the reference zone is the velocity defined in the Fluid dialog box for that zone.

When plotting velocity vectors, you can choose to plot vectors in the absolute frame (the default), or you can select Relative Velocity in the Vectors of drop-down list in the Vectors dialog box to plot vectors relative to the translational/rotational velocity of the "reference zone'' (specified in the Reference Values task page). If you plot relative velocity vectors, you might want to color the vectors by relative velocity magnitude (by choosing Relative Velocity Magnitude in the Color by list); by default they will be colored by absolute velocity magnitude.

You can also generate a plot of circumferential averages in ANSYS FLUENT. This allows you to find the average value of a quantity at several different radial or axial positions in your model. ANSYS FLUENT computes the average of the quantity over a specified circumferential area, and then plots the average against the radial or axial coordinate. For more information on generating XY plots of circumferential averages, see Section  29.9.5.

See also Section  29.10 for details about turbomachinery-specific postprocessing features.