[ashtonJ]

Hi there

A fluid flow which has a streamwise velocity component (along X axis) and a tangential (spiral) velocity component (around X axis), enters a pipe.

Streamwise velocity component: 0.12 [m/sec]*(1-(r/1.5 [mm])^2)
tangential velocity component: 0.06* r/6*1.5 [mm]
radial velocity component: 0


in "Boundary details", I choose Cyl.Vel. Component option and enter the above expressions for the velocity components. In axis definition, I choose "Coordinate axis" option but I don’t know which axis should be selected for "Rotation axis". If entering flow rotates around X axis, X axis should be chosen as "Rotation axis"?

I have another problem about Reynolds number. when I calculate the Reynolds number at inlet, it would be about 100, but when I check the velocity and Reynolds number in "Average Scale Information" in CFX Solver, their values are too large.(7*1E+5 [m/s],2.4*1E+6]. This issue causes my solution to be diverged.
Please let me know why "CFX Solver" shows large values for Reynolds and Velocity?

Finally, I don’t know in "Basic Setting" of inlet boundary condition, whether "Coord frame" option should be selected for my problem or not?

Regards,
Ashtonj