Learning Forum

[tumulpurwar]

Dear Peter

 

In ansys, if we do share topology it is almost equal to as we are welding different parts together..i want know if two things say columns are shared topoloy in ansys, means welded, what is dof it constrained and which one not?

In one of my working with structural assembly, i had one pillar sitting over one structural memeber in a big structural assembly.

 

now first i ran whole structure static simulations stresses were high near to foot of pillar, than i got intereted in knowing axial reaction at pillar foot, so i used fixed Boundary Condition(BCn) at foot of cylindrical pillar by using circular edge.

than i re run results this, time i got along with other results say von mises, Reaction force value at pillar foot too.....but problem after putting fixed constraint at foot of pillar, stresses came less there and higher stress shift to some other part of structure.

 

so i want know difference between  pillar foot welded with floor(called deck in shipbuilding) by shared topology and other thing is if pillar foot is applied Fixed Boundary condition?

 

 

[peteroznewman]

When the pillar shares nodes with the deck using Shared Topology, deformations in the deck and the pillar create high stresses at the base of the pillar.

When the foot of the pillar becomes a Fixed Boundary Condition, the deformation in the deck is also zero at that edge so the deformation and stress at the base of the pillar is much lowered.