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Recent content by adfergusson

  1. adfergusson

    Assigning material properties to each element

    I’m guessing that you don’t have the ability to get fibre orientation data for the bone but I do have a cool idea (well, I think its cool) of how you could assign orientations/anisotropic properties to each element. Once you have your model built with every element having its own nset, elset...
  2. adfergusson

    Assigning material properties to each element

    Its been quite a few years and I’m more of a powerpoint monkey these days too, but I’ve done something broadly similar with building models of composites from microscopy images (see photo). We have a program that would overlay a mesh on an image, identify the fibre orientation in each element of...
  3. adfergusson

    Low margin Composite Markets?

    Low cost/margin says things like particle filled composites such as glass filed nylon that is injection moulded. As cost/margin increases, things like SMC and BMC come into play. I can't really think of any notable low cost, margin and volume production and that's probably because low volume...
  4. adfergusson

    Composite structure analysis by hand

    Can't say I have much knowledge of the homebuilt aircraft market and I wasn't aware that sandwich constructions might feature much here; I had (very briefly) once entertained the idea of putting together a Glassair kit many years ago but don't remember it using much in the way of sandwich...
  5. adfergusson

    Bending moments transfer through adhesive bonded joint

    BlakMax; I initially thought you had misread, or simply missed, large parts of the content in the links. However, having looked at the papers you linked to it then became apparent that whilst you might have had some insight and experience that would have been uncommon back in the 80s, you appear...
  6. adfergusson

    Bending moments transfer through adhesive bonded joint

    A well designed adhesive bond should pretty much always be able to out perform a mechanical joint. However, the design of adhesive joints is rarely the straight forward matter that many people seem to think it is. To get an idea of an analysis process for a highly idealised (I.e. Pure mode 1)...
  7. adfergusson

    Composite structure analysis by hand

    Yep, composites are complicated and there are a huge range of physical phenomenae occurring over vastly different length and time scales. It is impossible to incorporate more than a few of these phenomena in any practicable analysis/model. Consequently, experimental testing (and an understanding...
  8. adfergusson

    Composite structure analysis by hand

    I'd recommend YouTube as a starting point for getting into numerical methods! I'd start simple with solving simple beam theory problems using Euler's method. There's a Khan Academy video on Euler's method that gives a simple and clear example of it; watch it and see if you can work out how to...
  9. adfergusson

    Composite structure analysis by hand

    I commend your intention to gain a solid grasp of the fundamentals of the mechanics of composite materials. If you are looking to, for example, be able to predict the response of a composite plate to a pressure load then there is a book by Reddy that is useful Link We've used the solutions in...
  10. adfergusson

    foam structure under compression with self contact

    Actually, you have another more important problem; your geometry is neither realistic nor periodic. For a start, those vertical beams that define the corners of you model are going to totally dominate the reponse of this structure under a vertical load and real foams do not have such uniform...
  11. adfergusson

    Young modulus optimisation over Geometically non Linear Frame Element (FEM)

    Hi Bruno, Regarding your three approaches: 1: Why would you be using the FE method here? If the purpose of this approach is to ensure you have a deep understanding of the underlying numerical method then I would expect that finite differences would be easier to understand an implement. If the...
  12. adfergusson

    Looking for a Heat Conducting Transparent Material for Very Hight Application

    Second link was dead, this should work: Link
  13. adfergusson

    Looking for a Heat Conducting Transparent Material for Very Hight Application

    This should work: Link Porbably worth tracking this guy down for some advice on it: [link...
  14. adfergusson

    Spherical indentation- load-displacement graph

    What other analysis have you done so far? At the least I think you'll need to do (if you have not already done so): 1) Use analytical solution to determine stress components as a function of depth and your materials using hertz contact (e.g. use AMES contact stress calculator and the links to...
  15. adfergusson

    HOW TO: External Python Modules from Abaqus Python Interpreter

    Huge thanks for this, its a really helpful post. I've wondered whether there was a way to do this and now I know!

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