# Inlet flow angle without specifying velocity components

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 October 14, 2019, 07:03 Inlet flow angle without specifying velocity components #1 New Member   Join Date: Aug 2019 Posts: 11 Rep Power: 5 Hello everyone, is it possible to define a flow angle at an inlet without specifying the velocity components of the flow vector? I am using pressure inlet but I also need to specify the angle. I appreciate your help. Best regards!

 October 14, 2019, 09:21 #2 Senior Member   Join Date: Jun 2009 Posts: 1,643 Rep Power: 29 Which angle do you have?, i.e. angle respect to which axis? The velocity components are the cosine of the angle respect to the axis, i.e. those are the angles you have

 October 14, 2019, 11:11 #3 New Member   Join Date: Aug 2019 Posts: 11 Rep Power: 5 I want to set an inlet angle of 30° wrt the x-axis. But I can't specify the inlet velocity components, because the inlet velcoity is part of the solution and not of the boundary conditions. I only define the inlet total pressure.

 October 14, 2019, 11:22 #4 Senior Member   Carlo_P Join Date: May 2019 Location: Italy Posts: 176 Rep Power: 6 Yes. You have to set up a coordinate axis. Then, you can use cylindrical component - axial component using the coordinate axis you define before. This should work. Let me know. Thanks!

October 14, 2019, 16:15
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Quote:
 Originally Posted by R4z0rX I want to set an inlet angle of 30° wrt the x-axis. But I can't specify the inlet velocity components, because the inlet velcoity is part of the solution and not of the boundary conditions. I only define the inlet total pressure.
Careful, there is no such option for Inlet Total Pressure unless the flow is supersonic.

I think you are confusing the direction velocity vector with the velocity vector itself for the subsonic setup combining Total Pressure + Flow Direction

Velocity Vector = Velocity Magnitude * Direction Velocity Vector
= Velocity Magniture * (Unit X, Unit Y, Unit Z)

Are you referring to the Unit Vector Component X/Y/Z components? or the Cartesian Velocity Components?

 October 15, 2019, 02:08 #6 Senior Member   M Join Date: Dec 2017 Posts: 495 Rep Power: 10 Perhaps you can make a slight change to the geometry to incorporate a chamfer of the desired angle and specify total pressure there? Not an elegant solution, but might be possible, depending on how big the inlet is compared to the rest of the model.

 Tags angle, cfx, inlet