Simulation: no solution provided

[Anonymous]

Hello,

At the moment I am considering a simplified aircraft fuselage.

Dimensions:

Diameter: 3500 mm

Thickness skin: 1 mm

Thickness floor beam: 9.6 mm

Length: 31420 mm

After applying a pressure of 0.064 MPa, it takes an enormous amount of time to solve.

After waiting for more than 1 hour, it still has not provided a solution.

We suspect it has something to do with the mesh settings or the quite large length size.

Our last resort would be to shorten the length of the fuselage, but eventually we want to

analyse bending as well, which will be affected by a different length.

Help would be greatly appreciated!

With kind regards,

AJ

[Andrew.Sartorelli · Accepted solution]

Hi @Anonymous,

Welcome to the Fusion 360 forum. I suspect there might be problems meshing this model, as Fusion 360 is currently limited to solid elements. When using solid elements to get accurate bending and membrane forces you really need to have 2-3 elements through the thickness, which for this model would mean elements that are 0.33mm thick. Meshing a model like this with an element size of 0.33mm would result in an excessive number of elements. For a model such as this we'd really want to use plate or shell elements, these are 2D elements that have a thickness defined for them, rather than solid elements that are 3D. Right now, Fusion 360 does not have the ability to generate such elements although I believe it is on the roadmap.

Looking at your account it appears you have student access to Nastran In-CAD and Simulation Mechanical, both have these have the ability to generate a plate and shell elements. I would recommend using either one of these at the moment if you are going to be carrying out similar analysis with thin components.

Best Regards,

Andrew

[Anonymous]

Thank you for the quick answer, we will look into that!