Lightning Strike Simulation over Composite ABAQUS. HELP

[anto_772]

Hi guys, I'm intending to carry out a simulation of an lightning impact over a compoiste plate using Abaqus (Coupled thermal-electrical analysis). First of all I put here the finite element model and boundary conditions:

-Specimen has 100mm width and 150mm lenght. Thickness of 4mm.
- Composite laminate are 32-ply quasi-isotropic [+45/0/-45/90]4s. Thickness of each ply 0.125mm
- Each lamina of composite laminate divided using 8-node isoparametric solid element to the thickness direction up to 1,5mm(0,0125mm x 12 ply).
- Orthotopic material properties calculated using rule of mixture were used for the elements deeper than 1,5mm to reduce number of elements.

Boundary conditions:
- Electrical potential at the bottom assumed to be zero (copper plate under the bottom of a specimen was electrically grounded)
- Eletrical potencial at side surfaces are zero
- Thermal radiation given fot upper and sides surfaces. Bottom surface adiabatic (Emissivity = 0.9 Environment Temperature =25ºC)
- Convective heat transfer around specimen ignored because extremely short period.

Loads:
- Impulse current of 40kA in the middle of the plate

The initial time increment was 0.01µs; the automatic time increment function provided from Abaqus was used. The resultant time increment was 0.001-0.1µs. After an impulse current test,no electrical load exist. Therefore general transient heat transfer analysis was conducted to save calculation time. The time increment was 0.1s; the calculation was terminated at 10s after lightning.

I want to reproduce this simulation with Abaqus. I create a solid part and create 12 sections for the first 12 plies. Then I create a composite Layup(solid) for the first 12 plies and I asign an isotropic material properties for the section below(deeper than 1,5 mm). I want help for introduce theses BC and if I'm modelling good the composite plate.

Thank you.

 

[Erik Panos Kostson]

Very different and very interesting.

I have never done this, but from a quick search on the internet there are some papers (videos), which use similar approach as you described.

I suppose the modelling will be 3D parts, and using 3D hex elements for instance (as you described I believe).

As for the boundary conditions.

The current density can probably be defined on a surface via the creation of a load in the GUI (choose perhaps electric category).
(the abaqus/cae manual should have more information on this)

As for the zero potential BC, that will be defined via the BC tool in the GUI. The video below might help on that:
Link

For thermal boundary conditions (radiation and convection), look at the following video for some tips:
Link
(Think defined as interaction in the GUI, and via surface film condition for convection and surface radiation for radiation)

Finally a coupled thermal electric step is created for this type of current generated heat analysis. The first video link covers this I believe. A second step can also be created (as in first video) after the current has been applied, thus there the heat transfer is analysed on its own (pure heat transfer step I believe no coupling needed after current is applied).

I hope this helps.

 

[LeeAPower]

Dear anto_772

Essentially, creating boundary conditions (BCs) are very straightforward.

For electrical BCs; go to BC, select electrical potentials, select all sides surfaces, and assign zero
For thermal BCs; go to interactions, select surface radiation, select bottom surface with emissivity and amb. temp

I worked on lightning damage prediction work. Below are some of my previous work.

https://onlinelibrary.wiley.com/doi/10.1002/pc.24502

https://onlinelibrary.wiley.com/doi/10.1002/pc.24535

Let me know if you need more advanced suggestions and assistants

Regard
Juhyeong