To define body orientation, one reference frame in your project must be designated as the Body Frame. The Body Frame can be used to compute far field flow direction, mesh refinement box orientation, and output force directions like lift, drag, and sideforce.
When defining body orientation, make sure that the axes are pointing from the center of gravity in the right directions:
The positive x-direction points out through the front of the body.
The positive y-direction points out through the right side of the body.
The positive z-direction points out through the floor of the body.
This convention is commonly referred to as an aircraft's stability axis.
To create a Body Frame and define body orientation:
Navigate to Frames & Motion in the control panel.
Click the + icon to the right.
Select Body Frame.
Specify Origin and Orientation
Note: Mesh refinement box orientation and flow direction are static and depend on the initial body frame orientation. The body frame having motion assigned to it does not impact these processes.
You can also use an existing frame as the Body Frame by checking the Use as Body Frame box.