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[Abhijeet25]

I had a doubt regarding static structural analysis, that do I need to consider the body mass and other component mass while doing static analysis here I am talking about Chassis.
And for considering mass of components I will be using point mass and considering whole body under gravity, will this be right method to consider mass if analysis with it has to be done.

[peteroznewman]

If you include a gravity load in a Static Structural model, the total mass of the model should equal the total mass of the real structure. It's good that you are adding a point mass, but often, there is non-structural mass distributed over the chassis, like wiring, and tubing, etc. Click on the Model and see in the Details window, the total mass of the model. Suppose it is less than the real mass, and the chassis is mostly made of steel. One way to bring it up is to edit the density of steel in Engineering Data and artificially increase the density until the total mass equals the real mass.

[Abhijeet25]

Thank you a lot sir.
Could you please mention the reason for adding actual mass (the logic behind it) like as I am using static structural so will the results get affect much by including masses, because I was thinking that majorly mass will affect in case of explicit dynamic analysis.
Please let me know if I am wrong at some point.

[peteroznewman]

Say the structural part of the chassis has a mass of 100 kg, and the non-structural part has a mass of 100 kg. If you solve the Static Structural model without the non-structural mass, you will only see half the deformation and half the stress compared with the correct values of deformation and stress when the non-structural mass is added. That's a very large error.

[Abhijeet25]

Thank you sir for solving my issue.

I was facing one more issue for face split option in ansys design modeler, I tried for face splitting of tube surface and it showed me the line for splitting the surface but when i generated it no change on the face was observed I tried it many times but the same problem was faced. It would be grate if you helped me with this.

[peteroznewman]

Create a Plane and split with that.

[Abhijeet25]

Thank you for replying,  actually I have tried parametric spline by choosing location selection mode and it worked.

[peteroznewman]

Please select a post and click the Is Solution link to mark this discussion as Solved.

[Abhijeet25]

But in case of static structural analysis equation (k*u=F(t)) there is no mass involvement seen in equation, so what does that equation mass stand for.

Also I tried analysis by considering mass for chassis and other system there was very small difference in value observed around 1.5 to 2 MPa.

So I think for large structural mass the value may affect considerably but not in case of vehicle weighing around 150Kg .