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Creating geometry dependent force
Posted 3 mar 2016, 08:57 GMT-5 3 Replies
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Hi,
I try to create a force that dependent on an angle, to simplify earodynamic forces. Therefore I created a variable "Angle" under definitions: Angle = asin(-t1z).
To check if my formula was right I plot the variable Angle and the result were as expected. However when I try to introduce a boundary load: Angle*1[N] I get this error:
Undefined variable.
- Variable: comp1.Angle
- Geometry: geom1
- Boundary: 6
Failed to evaluate Jacobian of expression.
- Expression: ((1/comp1.mbd.bndl1.selA)*comp1.mbd.bndl1.FTy)*dvol
Failed to evaluate Jacobian of expression.
- Expression: (comp1.mbd.bndl1.FTy*test(comp1.mbd.bndl1.uy)/comp1.mbd.bndl1.selA)*(dvol)
Has someone an idea how to solve this problem? A test simulation is added.
Thanks in advance!
Rijk
I try to create a force that dependent on an angle, to simplify earodynamic forces. Therefore I created a variable "Angle" under definitions: Angle = asin(-t1z).
To check if my formula was right I plot the variable Angle and the result were as expected. However when I try to introduce a boundary load: Angle*1[N] I get this error:
Undefined variable.
- Variable: comp1.Angle
- Geometry: geom1
- Boundary: 6
Failed to evaluate Jacobian of expression.
- Expression: ((1/comp1.mbd.bndl1.selA)*comp1.mbd.bndl1.FTy)*dvol
Failed to evaluate Jacobian of expression.
- Expression: (comp1.mbd.bndl1.FTy*test(comp1.mbd.bndl1.uy)/comp1.mbd.bndl1.selA)*(dvol)
Has someone an idea how to solve this problem? A test simulation is added.
Thanks in advance!
Rijk
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3 Replies Last Post 3 mar 2016, 12:06 GMT-5
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Posted:
8 years ago
Dear Rijk,
I advise you mail your post to: support@comsol.com
Best,
François Mandias
I advise you mail your post to: support@comsol.com
Best,
François Mandias
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Posted:
8 years ago
Hi,
It seems that the Angle variable is defined on edge 11, whereas the boundary load that's using it is defined on boundary 6. Defining Angle on boundary 6 instead, the simulation runs.
Best regards,
Magnus Ringh, COMSOL
It seems that the Angle variable is defined on edge 11, whereas the boundary load that's using it is defined on boundary 6. Defining Angle on boundary 6 instead, the simulation runs.
Best regards,
Magnus Ringh, COMSOL
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Posted:
8 years ago
Thank you for the replies! The comsol support helped me out.
Because the variable Angle is defined on another boundary as the load is applied. So I needed to create another variable or average operator that copies the local variable to a variable that is defined on the entiry geometry
The solution is attached.
Because the variable Angle is defined on another boundary as the load is applied. So I needed to create another variable or average operator that copies the local variable to a variable that is defined on the entiry geometry
The solution is attached.
Attachments: