2 Replies Latest reply on Jul 7, 2011 9:17 AM by Bill McEachern

    Dynamic Biphasic Analysis

    Anton Kvit

      Hello,

       

      I am looking for any nonlinear FEA software available that can dynamically analyze movement of a biphasic (porous solid saturated with liquid) tissue. We are trying to get a dynamic model of vocal fold vibration. I am wondering if Solidworks would be able to model such tissue. A lot of FEA software has biphasic material analysis and dynamic analysis separately, but I have not found any software yet that can dynamically analyze biphasic tissue. We would like a poroviscoelastic biphasic model that is able to describe some or all of the following: liquid motion, solid stress fields, solid-liquid interaction, continuity and momentum equations that describe momentum exchange between the liquid and solid components of the vocal fold tissue.

       

      Thank You for any input,

      Anton Kvit

        • Re: Dynamic Biphasic Analysis
          Kevin Corr

          Ansys has coupled fluid structure interaction in ansys multiphysics wherein it integrates its results from ansys CFX flow package with deflection results from a static nonlinear analysis. Each increment of the stiffness matrix is solved and handed over to the fluid package for iteration of fluid regime. In turn, the reaction forces are evaluated to match up with the fluid kinetics and handed back over to the nonlinear solver to use as new boundary conditions for solid structure deformations. That completes the loop. Many loops later you have a progression of fluid structure interaction. I don't think you will find this in a bargain code like flowsim/sim premium.

          • Re: Dynamic Biphasic Analysis
            Bill McEachern

            If what you are seaking is a weakly coupled solution then ANSYS would be a long way down my list as you will need a very good non-linear code and this is not exactly ANSYS's strong suit. You need either MSC MARC ( I like it best myself) or ABAQUS and the coupling to the fluid code may or may not be required - dpending on exactly what is going on and what is available in the NL code but probaly required based on the limited description supplied. It is a bit trickier if the porous media's properties change due to the fluid parameters. That kind of coupling would be a bit more rocket sciency than your more commonly encountered FSI problem.

             

            Your other option is a strongly coupled explicit solution particularily if the real time to be solved is relatively short  - given it is a vocal thing I would assume it means 20 to 20KHz. You are probably better served using either LS-Dyna or MSC-DYTRAN wich are known as ALE codes. I think given the nature of the problem that DYTRAN might be the better option as short duration events like air bag inflation/blast simulation etc are more its cup of tea but it would require more thought and consideration of what the complexities are. You can get access to both through MSC though which might be a bit simpler in one respect. They also have a very good consulting group should you need it - which you likely will. ANSYS alos has code of this type though I don't believe it is as well adopted as the others - name escapes me at the moment - AUTODYN might be it.