Simcenter STAR-CCM+ Why Doesn't the Radial Table's 'R' Parameter Align with the Geometrical Plane's Radius? – Understanding the discrepancy

In STAR-CCM+, radial tables are typically set to reference the global laboratory coordinate system by default. However, if the plane of interest within a simulation isn't aligned with the cylindrical coordinates of this global system, the 'R' values extracted in the radial table may not accurately represent the geometrical diameter of the simulation domain. This misalignment can lead to inaccuracies in subsequent analyses or post-processing tasks.

To ensure that the 'r' values in a radial table correspond correctly to the geometrical diameter, it's essential to create a local cylindrical coordinate system that aligns precisely with the plane of interest. When creating this cylindrical coordinate system, users should ensure they provide the correct inputs for properties such as the radial axis and the vector on the R-Theta input plane. Once this local coordinate system is established and configured accurately, users can then add the 'r' radius option from the cylindrical coordinate system to the radial internal table. This can be done by navigating to the scalar properties in the radial internal table, selecting 'Position > Cylindrical Coordinate > r', and adding it alongside other quantities of interest.

By incorporating the 'r' radius option from the correctly defined cylindrical coordinate system into the radial internal table, users can compare it with the radius derived from the laboratory coordinate system. This comparison ensures that the radial table displays two radius values: one from the cylindrical coordinate system and the other from the laboratory coordinate system. With the correct cylindrical coordinate system configured, the 'r' values in the radial table accurately.