Another option is to take a course a university through distance learning, Im betting you will learn a lot more. Of some of the ones I know are UT-Arlington, GaTech, U of I...Im sure there are more. Im pretty sure you can take them without applying for a degree.
It looks like it has not converged yet. Instead of just adding elements, refine the mesh locally (where the S.C.) is and see if it converges faster.
Second, are you sure you are applying the theory correctly? When using the S.C. are you subtracting out the hole diameter from the area when...
If there is a compressive load at any point in the structure, there will be an eigenvalue that corresponds to buckling. Basically, your answer is a solution will exist. Whether or not the soution is on importance is another question. Think of it this way, if you have even one element that is...
I think the problem is in the formulation of the elements. You see, according to classical laminate theory, you assume that the shear strains are zero. Of course that is not true. You have to include additional theory in order to account for this. If you have the composites lecture (can...
As far as the stress singularity goes, I would suspect this would not affect the natural frequency. Only if it is actually connected at this point and has a relatively large displacement at this point will it matter. Otherwise, say if it were a sharp corner, nah, it wont matter, why would it...
Well, you are trying to do an impact analysis on foam and dont know if it has a poisson ratio? Pretty ambitious. Is the foam a blown foam, a syntactic. Yes it has a poisson ratio, pretty much as every material in existance. If you find what type of foam you are using, you can use a vendor...
I believe what is going is that you need to realize the difference between an applied force and an applied displacement. If a force is applied to a structure, the structure will respond and deform according to the structural properties. If a displacement is applied, then at the application...
What are you talking about ? That is exactly what you want to do. This is the basic understanding of calculus and limits. There is no problem with having constant strain across a very small element. Hit the books again.
Convergence of discretization error is usually not where an analysis job goes bad. Far more often is the model incorfectly setup than error due discretization. And if your restricted to a p-element code you may have already lost the battle consdering the codes are usually inferior...
Blah blah, the stress is there. If your geometry is truly sharp, then expect high stress. But ya know what, there is thing called plasticity. This may or may not be a big deal, but what should be looked at is the type of material (mostly its ductility) and what type of fatigue loading you expect.
Its also only a linear code and there is less control of the mesh (good in some respects, but less flexible). Beyond the surface, it lacks much of the detail better packages have.
There is a program called JL Analyzer, do a search for it. Its not that great, but will do simple things and I believe the node limited version is free.
Also, for about $300 you can get a node limited version of ANSYS/ED. You dont have to be in school to get it though, (I think). It can do...
If you exibhit yielding in the material then you will notice a differnce with each cycle. You need to use a plastic material model that captures the bauschinger effect.
If it is not plastic then it will not matter if you have one or 5 cycles.
My point is that how can someone seperate the straightforward problem from the one that isnt unless they have the background in such nature ? If your satisfied with results that are very accurate sometimes, but garbage other times great...do you know which are wich though ?
The reality is that...
Let me give you a simple example of a true story I have run across. An "analyst" was doing a "simple" problem of solving the deflection of thin sheet fixed in all DOF on its edges with a pressure load applied. Seems very simple right ?
Why then were his results 5X, yes...
