eugenec
Aerospace
- Mar 21, 2012
- 6
Hi
I'm trying to simulate wave propagation in a 8-ply quasi-isotropic composite beam with mid-plane delamination using Abaqus/Explicit.
I modelled the beam ply-by-ply using solid elements C3D8. Each layer of elements thus represents 1 ply. As this is a beam, there is only one element in the beam width direction.
I created a mesh split for the delamination. Basically at where the delamination is located (laterally centred along the length of the beam), each sublaminate is represented by 4 layers of elements. To prevent cross-penetration of the nodes, I defined contact properties for the delamination surfaces. The properties used are tangential 'frictionless' and normal 'hard' contact allowing separation.
A bending (transverse) wave is excited at one end of the beam and allowed to propagate to the other end of the beam.
The problem arises when the wave travels across the delaminated region. At the delaminated region, the delamination surfaces begin to contact, resulting in normal surface forces which act to prevent surface penetration. However, in my model as the wave travels through the delaminated region, the delamination simply opens up to a shape of a ruby ball between the two undamaged regions of the beam. It seems that the normal forces between the delamination surfaces where contact properties have been defined for are pushing the surfaces far apart instead of merely separating them. I don't think this is representative of the actual physics. When I turn off contact properties and allow the nodes to cross penetrate, I do not have this issue.
Does anyone know what the problem might be and how can I fix it to prevent the strange opening from occurring?
Thank you.
Regards,
eugenec
I'm trying to simulate wave propagation in a 8-ply quasi-isotropic composite beam with mid-plane delamination using Abaqus/Explicit.
I modelled the beam ply-by-ply using solid elements C3D8. Each layer of elements thus represents 1 ply. As this is a beam, there is only one element in the beam width direction.
I created a mesh split for the delamination. Basically at where the delamination is located (laterally centred along the length of the beam), each sublaminate is represented by 4 layers of elements. To prevent cross-penetration of the nodes, I defined contact properties for the delamination surfaces. The properties used are tangential 'frictionless' and normal 'hard' contact allowing separation.
A bending (transverse) wave is excited at one end of the beam and allowed to propagate to the other end of the beam.
The problem arises when the wave travels across the delaminated region. At the delaminated region, the delamination surfaces begin to contact, resulting in normal surface forces which act to prevent surface penetration. However, in my model as the wave travels through the delaminated region, the delamination simply opens up to a shape of a ruby ball between the two undamaged regions of the beam. It seems that the normal forces between the delamination surfaces where contact properties have been defined for are pushing the surfaces far apart instead of merely separating them. I don't think this is representative of the actual physics. When I turn off contact properties and allow the nodes to cross penetrate, I do not have this issue.
Does anyone know what the problem might be and how can I fix it to prevent the strange opening from occurring?
Thank you.
Regards,
eugenec