Learning Forum

[Deepesh]

How to find Polar MI and Diametric MI in Ansys Workbench? and what is Diamteric Moment of inertia? 

Thanks

[peteroznewman]

Deepesh, I recommend you do a search on Google to find out what Diametral Moment of Inertia is. I found this in < 1 minute.

In SpaceClaim, you must assign a Material to a solid body, then on the Measure tab, click Mass Properties.

[Deepesh]

Sir, when we assign material in Spaceclaim, we get only moment of inertia to be seen in the details.

[peteroznewman]

You get three moments of inertia.

[Deepesh]

So Sir, is the diametral MI here the third one. i.e Z axis ?

[peteroznewman]

You are showing Area Moments of Inertia because you have not assigned a Material in SpaceClaim.

There are two diametral MIs, and they have the same value when the object is a disk.

[Deepesh]

After assigning Titanium Ti material in spaceclaim

The geometry is a shaft/cylinder

Also, how do you know that material is assigned or not (Whether ts Area or Diamteral MI)? because only the value has changed, rest parameters are the same?

 

Thanks

[peteroznewman]

The units have changed too.

[Deepesh]

Area MI in the first photo has unit mm^5 whereas it should be mm^4??

Also, is there any other name for the diametral moment of inertia? 

[peteroznewman]

With no material assigned, it's a volume moment of inertia and I don't care about that at all.

I only care about the mass moment of inertia that is computed after a material has been assigned.

[Deepesh]

So, its basically before applying the material, it gives Area Moment of inertia?

After assigning material, it gives diamteral MI?

[peteroznewman]

No, with no material assigned, it's a volume moment of inertia.

After assigning a material, SC gives three mass moments of inertia.