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femur modeling

Hi!
I am building a model of femur(thigh bone) and aim at studying their stress and strain distribution on applying a pint load.I have built the model but it doesn't seem to compute,and i can't figure out why.Please check the model and point out the errors that need correction.


6 Replies Last Post Oct 19, 2012, 10:15 AM EDT
Posted: 5 years ago Oct 14, 2012, 3:04 PM EDT
In your model, mesh is not defined in all domains or on boundaries and also it is not fine enough for solver to converge the solution. And under Prescribed displacement you need to select boundary surfaces.
In your model, mesh is not defined in all domains or on boundaries and also it is not fine enough for solver to converge the solution. And under Prescribed displacement you need to select boundary surfaces.

Posted: 5 years ago Oct 15, 2012, 3:17 AM EDT
Hi

I can only stress: avoid using point or edge constrints, but only 1 level lower than domain => boundary loads. All other make singularities and it far more difficult to analyse your models

--
Good luck
Ivar
Hi I can only stress: avoid using point or edge constrints, but only 1 level lower than domain => boundary loads. All other make singularities and it far more difficult to analyse your models -- Good luck Ivar

Nagi Elabbasi Certified Consultant
Posted: 5 years ago Oct 15, 2012, 8:32 AM EDT
You are applying the bone material to the boundaries not the domains, and the same for the mesh. Both should be defined at the domain level unless you want to use shell elements.
You are applying the bone material to the boundaries not the domains, and the same for the mesh. Both should be defined at the domain level unless you want to use shell elements.

Posted: 5 years ago Oct 15, 2012, 9:17 AM EDT
Thank you for your valuable reply Sir.
I am stuck at an error saying "System matrix is zero".Is there a way to rectify it?
Thank you for your valuable reply Sir. I am stuck at an error saying "System matrix is zero".Is there a way to rectify it?

Posted: 5 years ago Oct 19, 2012, 10:01 AM EDT

Thank you for your valuable reply Sir.
I am stuck at an error saying "System matrix is zero".Is there a way to rectify it?

Though i have changed from point load to a boundary load,and want to plot von-mises stress distribution,the computation shows errors,with the system matrix being zero.Pls let me how to work on it?
[QUOTE] Thank you for your valuable reply Sir. I am stuck at an error saying "System matrix is zero".Is there a way to rectify it? [/QUOTE] Though i have changed from point load to a boundary load,and want to plot von-mises stress distribution,the computation shows errors,with the system matrix being zero.Pls let me how to work on it?

Posted: 5 years ago Oct 19, 2012, 10:15 AM EDT
If you would have followed mine and Nagi's suggestions, you should get the solution.
If you would have followed mine and Nagi's suggestions, you should get the solution.

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