mmartens
Mechanical
- Jul 17, 2001
- 24
I am currently using ANSYS for some pipe stress. I am trying to use PIPE elements but ended up going to SHELL elements because of the short comming of ANSYS PIPE elements. However, with SHELL elements our model is a monster. These are the problem that I am having:
(1) There is no way to turn off the end effects to model the pipe as a open-ended pipe element. The effect is zero on the real pipeline in the field but it is not negligible in the ANSYS model. And when we are doing a non-linear analysis the model does not converge to a solution with pressure and if we apply an end load/pressure we get large errors in the soluation. If we let it move freely on the ends we get unrealistic displacements. This leads to the second problem.
(2) If we go to a pipe element for buoyancy the same element does not allow for Plasticity and non-linear soluation and vice-vs-a. We would like to model a long section of buoyant pipe under 1 meter of water and when it reached the one meter limit the buoyant load is removed.
Just a shot in the dark does anyone know of a FEA package which might have a open-ended, buoyancy capable, non-linear elastic plastic pipe element. Just Asking???
(1) There is no way to turn off the end effects to model the pipe as a open-ended pipe element. The effect is zero on the real pipeline in the field but it is not negligible in the ANSYS model. And when we are doing a non-linear analysis the model does not converge to a solution with pressure and if we apply an end load/pressure we get large errors in the soluation. If we let it move freely on the ends we get unrealistic displacements. This leads to the second problem.
(2) If we go to a pipe element for buoyancy the same element does not allow for Plasticity and non-linear soluation and vice-vs-a. We would like to model a long section of buoyant pipe under 1 meter of water and when it reached the one meter limit the buoyant load is removed.
Just a shot in the dark does anyone know of a FEA package which might have a open-ended, buoyancy capable, non-linear elastic plastic pipe element. Just Asking???