Mixing plane geometry definition

Hbet

I am confused about the mixing plane geometry definition in Fluent. As you know there are 2 options : Radial and Axial. If the mixing plane is a cylindrical surface with an axis coincident with the axis of rotation, is this a radial mixing plane ? Or, if the mixing plane is a flat surface normal to the axis of rotation is this an axial mixing plane ?

The users manual P.16-30 states that: A Radial geometry signifies that the information at the mixing plane interface is to be circumferentially averaged into pprofiles that vary in the radial direction. This is the case for axial-flow machines, for example.

Could anyone enlighten me on this issue, and help me to have a correct understanding of the mixing plane geometry definition.

Thanks

Hbet