In CFD-Post, the additional turbo-specific variable "Rotation Velocity" has always a positive sign, independent from the sign of Angular velocity or the rotation axis. Is this correct?

"Rotation Velocity" is a vector quantity written to the results file by the solver, it is not generated by CFD-Post and is independent of the additional components calculated by Post. As a vector quantity, its behavior is consistent with other vectors in that the components are signed and the magnitude is always positive. What appears to be a scalar variable, "Rotation Velocity" is the magnitude of the vector of rotation velocity, and is always positive.

By defining the dot product of Rotation Velocity with Theta Direction, which can be easily calculated as a CEL expression to create a new user defined variable, the new variable will have the expected sign, corresponding to the sign of the Angular Velocity:

My Rotation Velocity = Rotation Velocity X * Theta Direction X + Rotation Velocity Y * Theta Direction Y + Rotation Velocity Z * Theta Direction Z

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