I normally only plot the translation for this type of result to visualize the displacement if the structure. Patran will display the nodes according to the x,y,z eigenevector results.
If you want to calculate the normal modes of a 3D FEM in Nastran, you will need to define the density of the material for the elements in your FEM. What are you modeling? Is it made of bar or beam elements, or solid/shell elements?
The .db file is a Patran database file. Since it is binary, you won't be able to do anything with it except open it using the Patran software. It does contain geometry, nodes, elements, loads, material, properties, etc. I don't believe there is any way you can read the .db file into FEMAP since...
I entered engineering college back in 1981, and I wasn't even sure what an engineer did (I just took the advice of my high school counselor). I chose aerospace engineering which was a new option from the mechanical engineering department. Aeros took the same classes as the mechanicals, but we...
I my opinion, open positions currently in the commercial aerospace field are in very short supply. With companies like Boeing having layoffs, aerospace suppliers are also being hit with layoffs. It seems the aerospace defense and space fields are not affected much by the commercial aerospace...
Here's some suggestions:
[ol 1]
Make sure you have a relatively fine mesh if you want to look at stresses. Based on your dimensions, you may want to use an element edge length of 2 mm or even 1 mm.
By default, Patran will plot averaged results for fringe plots (which will miss absolute peak...
What kind of mesh do you have? Is it a shell mesh representing a long test sample with a rectangular section? Or, is it a solid mesh of a circular rod?
I'm assuming you tried running this job from within the Patran application. If you did this, did you see any error messages in Patran when you ran it? Did any files get generated in the same folder as the Patran database you're working with (like, .f04, .log, etc.)? Finally, can you confirm that...
When you checked the f06 file, did you see any actual results printed in there? Like, displacements, constraint forces, etc? Next, it may be that your default Patran settings is requesting a different results file format and not the xdb file. For example, a MASTER or OP2 results file.
Can you...
In my opinion, learning any FEA software can be beneficial for your overall knowledge. In general, most aircraft companies use Nastran for linear analysis and Abaqus for non-linear analysis. As such, if I had a choice, I would learn Nastran or Abaqus.
Although that surface appears to be 4-sided, it may not be. It might have more than 4 vertices and thus more than 4 edges. You could delete that surface then recreate it by selecting the two opposite long edges. This would give you the 4-sided surface that you want and then you could mesh it...
I've been working as an engineer for 33 years now, the majority of the time with FEA. I've worked at 7 different companies, big and small. Here's my thoughts on this subject:
Before you start on a project, think hard if you can do the analysis using hand calcs. Often times younger engineers...
