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hamoudi June 17, 2009 02:50

Swirl Velocity
Hello Everybody,

I have a 2D simulation with swirl my geometry is in cylindrical coordinate
The two velocities Vr and V (theta)
please if any one know for corrcting me this information
is it the velocity V (theta) responsible for the swirl or not
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i have another question for cheking this formula

for transformation from cylindrical coordinate to cartesienne coordinate

U= Vr cos (theta)-V(theta) sin (theta)
V= Vr sin (theta)+V(theta)cos (theta)

Thanck you very Much

f-w July 6, 2009 15:01

I assume when you say 2D, you imply 2D axisymmetric ...

Yes, V_theta is the swirl velocity.

Your transformation from cylindrical to cartesian coord. systems is correct.

Be careful how you use this, are you evaluating swirl velocity, or setting up boundary conditions with swirl velocity?

juzer_700 July 7, 2012 01:07

Swirl velocity.

I am trying to simulate axisymmetric flow in FLUENT.

I am required to calcutae the Axial component, Radial and Tangential component.

I know the mass flow rate and Swirl number. How to calculate the components. Can you guys help me out. I am new to this. Please

Blanco July 18, 2012 07:03

I will assume that you have a sort of cylinder in your geometry...
create a cylindrical coordinate system (r,theta,z) on the axis of the cylinder, oriented in such a way that the z axis follow the cylinder axis...
Then you have your components:
radial comp. = x component on the cylindrical coord sys (r,theta,z)
tangengial comp. = y comp. ...
axial comp. = z comp...

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