SteRos
Mechanical
- Nov 17, 2016
- 1
Dear all,
I am still quite the beginner with ABAQUS:
I have a geometry (imported STEP from Creo / PRO/E) where two steel pipes are sliding through a steel "house", each hole diameter in the house matching the pipe diameter and the pipes are sliding through these holes.
I have set a surface to surface contact between the pipes and the inside of the holes, with a penalty friction formulation.
What I want:
I want to apply a force (experimental values, inserted as amplitude) on the pipes in order to get stresses/deformation when the pipes are moving.
I have run some different cases:
1) Friction 0.3 - Displacement control on surface (uniform)
Pipes move, but there is significantly more stress in the left pipe than in the right pipe.
2) Frictionless - Displacement control on surface (uniform)
Pipes move and stress is equal on both pipes
3) Frictionless - Dummy load of 10 N in axial direction
Error: Displacement increment too large.
4) Friction: 0.06 - Dummy load of 10 N in axial direction
Pipes produce equal stresses but do not move.
5) Friction: 0.3 - Dummy load of 10N in axial direction
Pipes dont move and stresses are significantly larger in left piple (see 1)
6) Friction: 0.3 - Actual load input in axial direction
Same as 5.
These are my warning messages every run:
Whenever a translation (rotation) dof at a node is constrained by a kinematic coupling definition the translation (rotation) dofs for that node cannot be included in any other constraint including mpcs, rigid bodies, etc.
Not all the nodes that have been adjusted were printed. Specify *preprint,contact=yes for complete printout.
MPCS (EXTERNAL or INTERNAL, including those generated from rigid body definitions), KINEMATIC COUPLINGS, AND/OR EQUATIONS WILL ACTIVATE ADDITIONAL DEGREES OF FREEDOM
4955 elements are distorted. Either the isoparametric angles are out of the suggested limits or the triangular or tetrahedral quality measure is bad. The elements have been identified in element set WarnElemDistorted.
I have some questions:
1) HWhat are possible reasons that I don't get any displacement when forcecontrol but get when i displacement control?
2) What impact could distorted elements have and what are the best ways to solve the issue? When I tested adaptive mesh it dimply deleted the pipes entirely.
Thank you for helping me out,
BRG,
Stefan
I am still quite the beginner with ABAQUS:
I have a geometry (imported STEP from Creo / PRO/E) where two steel pipes are sliding through a steel "house", each hole diameter in the house matching the pipe diameter and the pipes are sliding through these holes.
I have set a surface to surface contact between the pipes and the inside of the holes, with a penalty friction formulation.
What I want:
I want to apply a force (experimental values, inserted as amplitude) on the pipes in order to get stresses/deformation when the pipes are moving.
I have run some different cases:
1) Friction 0.3 - Displacement control on surface (uniform)
Pipes move, but there is significantly more stress in the left pipe than in the right pipe.
2) Frictionless - Displacement control on surface (uniform)
Pipes move and stress is equal on both pipes
3) Frictionless - Dummy load of 10 N in axial direction
Error: Displacement increment too large.
4) Friction: 0.06 - Dummy load of 10 N in axial direction
Pipes produce equal stresses but do not move.
5) Friction: 0.3 - Dummy load of 10N in axial direction
Pipes dont move and stresses are significantly larger in left piple (see 1)
6) Friction: 0.3 - Actual load input in axial direction
Same as 5.
These are my warning messages every run:
Whenever a translation (rotation) dof at a node is constrained by a kinematic coupling definition the translation (rotation) dofs for that node cannot be included in any other constraint including mpcs, rigid bodies, etc.
Not all the nodes that have been adjusted were printed. Specify *preprint,contact=yes for complete printout.
MPCS (EXTERNAL or INTERNAL, including those generated from rigid body definitions), KINEMATIC COUPLINGS, AND/OR EQUATIONS WILL ACTIVATE ADDITIONAL DEGREES OF FREEDOM
4955 elements are distorted. Either the isoparametric angles are out of the suggested limits or the triangular or tetrahedral quality measure is bad. The elements have been identified in element set WarnElemDistorted.
I have some questions:
1) HWhat are possible reasons that I don't get any displacement when forcecontrol but get when i displacement control?
2) What impact could distorted elements have and what are the best ways to solve the issue? When I tested adaptive mesh it dimply deleted the pipes entirely.
Thank you for helping me out,
BRG,
Stefan