Nastran in CAD – Idealization


Having access to the Autodesk Product Design and Manufacturing Collection gives you access to Nastran in CAD.  Nastran is an acronym formed from NAsa STRucture ANalysis.    Pretty neat hey!

If you have used the simulation in Inventor then you should be able to easily navigate to the Nastran interface from within the Inventor environment.  Simply open the Environments tab on the Ribbon and select Autodesk Inventor Nastran.

There are so many more options available here but never fear.  After a few examples you get used to all the different jargon, which buttons to press in which order and once that is done you can concentrate on the more important stuff like your results.

One of the most important parts to any Simulation is how to get the elements and nodes correct for the different simulations that are run.  Not only to get the correct results but also to simplify the model so that it can run as quickly and efficiently as possible (without compromising the results)  Nastran accomplishes this by idealizing the model.

When activating the Nastran environment the part will idealize initially as a solid element.

You can then make changes in the Idealizations dialog box to change it to either a shell or line element.  These idealizations are unique and will have a unique identifier to it ie 1,2,3 etc.

To visualize the type of element that is created for the different idealization you can use the following.

  • Solid takes the shape of 3D Linear and parabolic tetrahedral elements
  • Shell takes the shape of 2D quadrilateral and triangular elements
  • Line takes the shape of 1D elements with 6 degrees of freedom

I would strongly recommend getting to know what each of these elements (idealizations) are and where to use them, as each one will benefit the different simulation shapes that you will be presented with in your designs.