Learning Forum

[Sara]

Hello,

I know that bodies are assigned a material in Mechanical workbench with the default as Structural Steel, but I created my own material and assigned it to the structural Body. 

My question here is does Ansys consider the density of the material with regards to the design and size of the body and assigns a certain weight to it by default? If so can I manually assign a weight to the body, for example I want my structural body to be made of Aluminum alloy material and It should have a weight of around 250lbs how can I add that weight to the body (considering this as a static structural analysis) and Is it mandotary to always add a weight to the structure no matter what analysis you are doing?

Thank you

[peteroznewman]

Hello Sara,

In Engineering Data add a Physical property of Density. The mass of the part will be density*volume. In Static Structural add an Inertial load of Standard Earth Gravity. That will cause the self weight of the part to be included. 

If you only want the stress due to applied forces and ignore self weight then you don't need any of the above. 

[Sara]

Hello peteroznewman,

Thank you for your answer! In that case adding the standard earth gravity would ansys consider it at the center of mass by default or do I have to create a new cooradinate system at the center of the body? because right now my part has it's coordinate system at a different point other than in center.
Sorry that due to disclosure I am unable to share a snippet of the model.

[peteroznewman]

Hello Sara,

Gravity acts in the direction chosen on each element in the model individually. Only if the direction you want gravity to pull is not aligned to a global axis would you need to create a local coordinate system at the desired angle. 

[Sara]

Peteroznewman, I think I understood now. Thank you!