[yohey]

Hi.

I'm using OpenFOAM-1.6.x on Ubuntu 8.04 and in trouble with `pressureDirectedInletVelocity' boundary.


I'm working on the attached case. This case contains direction-fixed 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

[aliqasemi]

Yohey[/QUOTE]

Originally Posted by yohey

Hi.

(1) Next, I tried with more precise value.

inletDirection uniform (0.70710678 0.70710678 0);

But, calculation fails with this boundary.

Yohey

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.

[akashjangid]

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 !!