2D Pressure Vessel analysis
2D Pressure Vessel analysis
(OP)
Hi,
When I apply an external pressure load on a 2D model of a cylinder (plane strain analysis), I start to get rigid body motions.
Why would ANSYS WB create rigid body motions for an elliptical cylinder with equal pressure applied on the outside circumference?
When I apply an external pressure load on a 2D model of a cylinder (plane strain analysis), I start to get rigid body motions.
Why would ANSYS WB create rigid body motions for an elliptical cylinder with equal pressure applied on the outside circumference?





RE: 2D Pressure Vessel analysis
RE: 2D Pressure Vessel analysis
Apply appropriate restraints in the X and y directions and you'll be fine.
RE: 2D Pressure Vessel analysis
RE: 2D Pressure Vessel analysis
Even if you have a perfectly symmetric body, you must constrain your displacements. It is necessary because that's the way that the finite element technology works. To solve a linear problem, the software create a matric system K*U=F. If you don't specify any restraint, U = 0 and the system cannot be solved. The software add weak spring to stabilize the model.
In your cas, I see two options of constraint
- Use Weak spring and with probe option verify the force in each direction. If it is negligeable, your solution is near the reality.
- Create a line in the symetri plane of your model. Fix vertically a dot of the end of the line and fix horizontally the line. So the model will be stable.
Regards,
Michael Page
IDÉA Innovation PME