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October 6, 2009, 04:38 
trouble with `pressureDirectedInletVelocity'

#1 
New Member
Yohey Ishizu
Join Date: May 2009
Location: Tokyo, Japan
Posts: 6
Rep Power: 7 
Hi.
I'm using OpenFOAM1.6.x on Ubuntu 8.04 and in trouble with `pressureDirectedInletVelocity' boundary. I'm working on the attached case. This case contains directionfixed boundary as inletDirection uniform (1 1 0);But, with this condition, the velocity in the mesh next to boundary is dobuled. This is because of `operator=' in `pressureDirectedInletVelocityFvPatchVectorField.C '. fvPatchField<vector>::operator=(inletDir_*(inletDi r_ & pvf));So, I modified the `inletDirection' as (1/sqrt(2) 1/sqrt(2) 0). inletDirection uniform (0.707107 0.707107 0);This worked correctly. (1) Next, I tried with more precise value. inletDirection uniform (0.70710678 0.70710678 0);But, calculation fails with this boundary. (2) Actually this problem is derived from `pressureDirectedInletVelocityFvPatchVectorField.C '. So, I modified such sentence in this file as fvPatchField<vector>::operator=(inletDir_*(inletDi r_ & pvf)/magSqr(inletDir_));This modification also crashes calculation. I can't understand these behavior of (1) and (2). Would anyone help me to find the cause of these problems? Sincerely. Yohey 

August 10, 2011, 12:42 

#2 
New Member
Ali Q Raeini
Join Date: Feb 2010
Posts: 21
Rep Power: 6 
Yohey[/QUOTE]
This is because some of the faces in the patch are normal to the vector you specified for inletDirection, which causes a division by zero in the file pressureDirectedInletOutletVelocityFvPatchVectorFi eld.C. Changing the code or the value for inletDirection should fix the problem. I had the same problem using using OF.1.7.1, nearly two years later. 

October 4, 2013, 12:15 
Inlet Angle

#3 
New Member
Akash Sharma
Join Date: May 2013
Location: Paris
Posts: 15
Rep Power: 3 
Hello
I am doing simulation on a rotor blade. Does anyone know how to give the inlet angle like this (which depends on z and y) dir_cos1 = 4.04 dir_cos2 = EXPR{57.2958*(acos(0.07045*(z/sqrt(z*z+y*y))))} dir_cos3 = EXPR{57.2958*(acos(0.07045*(y/sqrt(z*z+y*y))))} Thanks !! 

Tags 
boundary condition, inlet 
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