Foam Model

[JohnChisholm]

I have been asked to model a volume of open cell foam.

I can obviously model a cube as the etremities of the volume, but how would I create a pattern of random sized voids within the cube.

I would want to control the size, position & orientation of the voids with parameters such that I can change these to achieve diferent densities of foam.

Even if the voids were all a constant size (although in practice they are not) it would still be useful.

Any Ideas ?

Thanks

[mrattray]

Why?

[JohnChisholm]

Yes, it does seem like a strange thing to model, but it is actually quite critical to a R & D project that my company is developing. The properties, i.e. volume & mass, are important with regard to heat transfer (the foam is actually a metal foam).

Regards 

[mrattray]

That doesn't help me understand why you need the actual cells to be modeled. Why not just make some custom materials with the properties required?

[JohnChisholm]

That's okay we have now managed to work this one out for ourselves.

Regards

John Chisholm
Design Draughtsman


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Whittaker Engineering Limited





Hindwells

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jchisholm@whittakereng.com

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[mpatchus]

I for one would be curious to know your solution.

[JohnChisholm]

Here goes !!

I created a surface model of a geometrical shape called a "tetrakaidecahedron" which is the approximate geometry of the voids within the metal foam structure.
I gave each of the twelve surfaces a thickness creating a solid model of the geometrical shape.
I then offset the perimeter outline of each surface by a predetermined distance giving a sketch on each face.
The sketch of the offset profile was then extruded by the thickness of the face.
This resulted in something resembling a wire frame model of the Tetrakaidecahedron, which I could then give properties to. Hence giving mass & volume.

I then created an assembly file where I constrained numerous copies of the Tetrakaidecahedron together to form a model equivalent to a cubic measure of the metal foam.

I could then change the offset dimension on the sketch in order to thicken or thin the wireframe member to achieve a different density of foam.

Turned out to be fairly simple in the end. Surprised you didn't know this !!

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This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. E-mail transmission cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore does not accept liability for any errors or omissions in the contents of this message, which arise as a result of e-mail transmission. If verification is required please request a hard-copy version.

[cbenner]

Sounds pretty awesome...if you're able to do so... share a picture.

Some of the simplest solutions out there are to questions that most people never had any reason to ask.  I'm glad you worked it out.