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fitting an elastomeric material

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jcmbl

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Joined
Oct 22, 2004
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GB
Hi guys,

I'm using a hyperelastic foam core in my FE model. I am using Abaqus to fit the material so that I can optimize the parameteres defining the foam core during bending. The parameters are: mu (i.e., shear modulus), alpha (i.e., shape of the stress-strain curve) and beta (i.e., shape of volumetric response) which is a function of nu (i.e., Poisson's ratio).
Obviously the design space initally chosen was quite large, ranging mu=(10^-5, 4); alpha=(-25, 25); nu=(-0.8, 0.4), since I has no idea where exactly to look for feasible parameters.
In Abaqus, I have defined the order of the hyperfoam N=2, to have somewhat a sensitivity wrt parameters.

After optimization, whereby minimizing a functional related to the volumetric expansion and bulges on outer skin, which has a great impact on the aerodynamics, I got these values:
mu1 = 2.455926, alpha1 =-15.338828,
mu2 = 3.370209, alpha2 =-11.944445,
nu1 =-0.422784, nu2 =-0.610916.

I was just wondering how feasible is this design space and how feasible are the optimized parameters in terms of manufacturability. I have no idea how to assess these or if they represent a real material.

Please give me a hint on these.

Cheers,

J

 
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