So, I was just doing some Finite Element Analysis (FEA) to figure out what would be the effect on the stiffness of a cantilever beam if another beam is attached to it on its free end.
Below shows the two cases I am using as examples.
I am only conducting geometric linear analysis i.e. change of stiffness of the green beam is not tracked by the solver during loading. Here are the deformation results for this beam.
So apparently, the deformation along Z axis only changes by a magnitude of 0.018 mm of the green cantilever beam. But my question is that is this change in deformation because of the addition of the vertical gray beam on the free end of it, or its just a result of the numerical errors coming from the FEA solver's nature?
I mean if the deformation is changing for the green body, then it means that its stiffness has changed since the solver is linear and same load is applied. So attaching another body, like the gray body in this example, somewhere along the length of the green body should change its stiffness (and therefore its resulting deformation) or not? And how would you anticipate the affect of increasing the height or area of connecting face of the gray body to green body would affect the green body's stiffness and its deformations?
If I talk about purely Statics, then the bodies are assumed to be Rigid. If I talk about Mechanics of Materials, then bodies are assumed to have very small deflections and rotations. Plus, the beam thoeries like Bernoulli and Timoshenko assume that the cross section is constant throughout the length of the beam. But what is the reality for this example I have mentioned here in my post?