how does chefem treat permeation in multilayer?

Thread by Julia Emsley on 29 Nov 2010 at 21:20:46 
Hi,

How does CheFEM treat water permeation in multilayer materials? My FEM software is not able to deal with solubility and diffusivity in a sequence of nanoscopic and microscopic layers (and yes, I know it is based on Fick's first and second law, but I justed wanted to obtain a worst case indication of the permeation, but even that is seemingly too much...).

Thanks for your help.

Kind Regards,
Julia

    Comment by Composite Agency on 06 Dec 2010 at 17:56:38  | |responses: 0|
    Dear Julia,

    CheFEM usually uses Finite Difference Methodology (FDM) for solubility and diffusion calculations regarding multilayer / laminate materials. Large magnitude differences in layer thicknesses (micro and nano layers) and interfacial concentrations can be handled much more efficient and effective with FDM (compared to FEM). Subsequently, stresses and strains are quantified using classic laminate theory and/or FEM.

    Especially if the laminate is subjected to external stresses (a mechanical load), intrinsic stresses (complex shapes, 90 and 180 degrees bends) and/or residual stresses (thermal), FEM is the best method for the "after" processing/visualization.

    Is this helpful?

    Regards,
    Composite Agency