Modelling stresses in concentric cylinders
Modelling stresses in concentric cylinders
(OP)
I am working on a burst calculation on a cylindrical pressure vessel. I have this cylindrical vessel placed concentrically inside another cylindrical vessel which is acting as a reinforcement to the inner part. (The diametral clearance between the two cylinders is .005" approx.)
The thickness of the inner part is such that the standalone busrt calculations generate stresses beyond the yield strength. But being placed inside the other piece (thin cylinder inside a thicker cylinder) helps it from plastically deforming.
How do I model this using COSMOS?
The thickness of the inner part is such that the standalone busrt calculations generate stresses beyond the yield strength. But being placed inside the other piece (thin cylinder inside a thicker cylinder) helps it from plastically deforming.
How do I model this using COSMOS?





RE: Modelling stresses in concentric cylinders
if so why model the interaction of the cyclinders ?
if you have to model it, you're dealing with a contact (non-linear) problem.
RE: Modelling stresses in concentric cylinders
Thanks for replying. The outer piece is of the same thickness as the inner piece and so would fail by itself as well.
The inner cylinder moves axially inside the outer piece.I want to keep the delflection on the inside cylinder in the elastic zone so that when the pressure on the ID is relieved, the OD of the inner cylinder can still slide inside the outer cylinder.
I am trying to obtain a rating as tests with 10000 psi on the inside cylinder plastically deformed the inner piece and it was hard to get it apart.
RE: Modelling stresses in concentric cylinders
RE: Modelling stresses in concentric cylinders
Don't know the diameter of your cylinders, but you seem to be playing with a micrometer in a blacksmith cave.
prex
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RE: Modelling stresses in concentric cylinders
Cheers
Greg Locock
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RE: Modelling stresses in concentric cylinders