Learning Forum

[ANUPAMA]

Hai,

Iam writing to seek your assistance regarding finite element analysis. I have done the analysis for a ship with web frames and stiffeners. But the maximum stress is concentrated on one region (The location where boundary conditions are provided). In that region the body is somewhat deformed. In real case the maximum stress should not occur in that region.

The maximum stress is coming on the regions where i applied the boundary conditions. When i change the locations of boundary conditions the maximum stress distribution also changes. But in reality the maximum stress should be in midship no? and the bottom and top regions should have almost same stress distribution. 

I have to provide the boundary conditions such that the reaction force at the support should be less than 1% of the displacement of the ship. But when i check the reaction force it is coming as some bigger value. Is there any way to reduce the reaction force occur in boundary conditions?

Kindly help me to fix this problem. 

[ErKo]

 

Hi

Look inertia relief perhaps – might be useful here:

https://simutechgroup.com/static-analysis-with-inertia-relief-in-ansys-workbench-mechanical/

Also weak springs might be worth looking at.

https://mechanicalland.com/explanation-of-weak-springs-option-in-ansys-solver-control/

 

Erik

 

 

[ANUPAMA]

Hai,

Thank you for your response. I have turned on the inertia relief but still i didn't get the proper stress distribution.

The maximum stress is coming at the location where boundary conditions are applied. Is there any way to change that?

 

[ErKo]

Hi

The whole point of inertia relief say for a free floating ship structure is so we do not have to use any restraints/boundary conditions :)

Search on inertia relief for ship or airplane structure for more info if the above is not clear.

Erik

[Avnish Pandey]

Hi,

Try refining and improving the quality of your mesh. Also check the loading and boundary conditions.