HOWDOO
Mechanical
- Aug 19, 2008
- 12
First Post!
Hi all, i'm hoping one of you may have had some eperience in applying pretensions to line bodies in Ansys. I've scoured the forums/google and found very lttle on the subject but I can't imagine it's not being widely used as it is an obvious time saver.
The geometry is a bolted flanged connection with a gasket located in between. I'll describe the steps i've taken:
1. The geometry has been mid surfaced.
2. The holes (bolt locations) have been used slice the geometry to create intersections at the bolt centres at either side of the connection. The holes themselves were subsequently deleted.
3. Points were generated at the intersections (on the flange surfaces only) and used to create the line bodies.
4. Cross-sections were assigned to the line bodies to represent the bolt shanks.
5. In workbench the contacts where set as follows:
i) Flange A - Gasket: Bonded
ii) Flange B - Gasket: Frictionless
The flanges themselves are restrained to a bigger model that has its own contraints preventing free body motion.
6. A pretension was applied to the line body however the line itself could only be selected as an edge when doing this?
The preload was active in Substep 1 and locked in Substep 2. A Simple gravity load was applied in the second step.
Following these steps I am getting unreasonable stresses. I've checked the mesh quality and if the contacts are initially open and can confirm they seem adequate. I've tried with large deflections on and off, I will admitt i'm not sure which one correctly applies here.
Am I missing something in my procedure? Any assistance would be greatly appreciated.
Alex.
Hi all, i'm hoping one of you may have had some eperience in applying pretensions to line bodies in Ansys. I've scoured the forums/google and found very lttle on the subject but I can't imagine it's not being widely used as it is an obvious time saver.
The geometry is a bolted flanged connection with a gasket located in between. I'll describe the steps i've taken:
1. The geometry has been mid surfaced.
2. The holes (bolt locations) have been used slice the geometry to create intersections at the bolt centres at either side of the connection. The holes themselves were subsequently deleted.
3. Points were generated at the intersections (on the flange surfaces only) and used to create the line bodies.
4. Cross-sections were assigned to the line bodies to represent the bolt shanks.
5. In workbench the contacts where set as follows:
i) Flange A - Gasket: Bonded
ii) Flange B - Gasket: Frictionless
The flanges themselves are restrained to a bigger model that has its own contraints preventing free body motion.
6. A pretension was applied to the line body however the line itself could only be selected as an edge when doing this?
The preload was active in Substep 1 and locked in Substep 2. A Simple gravity load was applied in the second step.
Following these steps I am getting unreasonable stresses. I've checked the mesh quality and if the contacts are initially open and can confirm they seem adequate. I've tried with large deflections on and off, I will admitt i'm not sure which one correctly applies here.
Am I missing something in my procedure? Any assistance would be greatly appreciated.
Alex.