Non-Structural Mass Deleted Between Iterations

[dlj2_msfc]

I currently have NSM added to my panels in my FEM to represent propellant fluid in order to get the appropriate loads.  I noticed that when I imported the plate elements, the NSM was not brought into the "Added Weight" field under the Options tab of the Sizing Form.  Therefore, when I iterated between HyperSizer and the FEM, the NSM was not carried through.  Is NSM something that can be read in by HyperSizer or do I just need to put those values back into the FEM between iterations?

[Phil]

Non-structural mass will be imported on the initial import of a model into HyperSizer if you turn on the "Import non-structural masses (NSM) from FEM and store as Added Weight" check box on the FEM Interface options dialog.  On the Project Setup form, after you specify the FEM file names, press the Import/Export Options... button to raise this form.

Note that you must turn this check box on BEFORE you import the model.  After the model is imported, this option is grayed out and is not available again unless the model is unimported.

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[dlj2_msfc]

Thank you for the help.

When I created a new project and checked that box the NSM came in.  However, it was not the same value I had in the FEM.  I originally thought it was because my FEM is metric and my project was in english.  But when I did them both metric, the NSM was still off.  Its off by a factor of 9.815.  Could there be a conversion issue or something else?  I have verified that the units I am using in the FEM is kg/m^2.

[Phil]

Is it possible that there is a WTMASS parameter card in the FEM?  If so, HyperSizer will read that card in and convert the masses to weights accordingly.  Also, there is a radio button where you can choose either mass units or weight units.  Try the "other value" from the one that was picked before importing your FEM.  It is possible for metric units, that this import could have the conversion backwards.  I will try to check it out.

[dlj2_msfc]

The WTMASS in the FEM is turn off, and it is not in the .dat file.  I have also tried to turn the "other" check box on/off between the Mass and Weight variables in HyperSizer and that didn't fix it either.  Please let me know if you find anything out.

Thanks

[Phil]

A support ticket has been created to investigate this issue.  When resolved, this topic will be updated.

[Phil]

This was a confirmed error with the import of non-structural masses from models with SI units.  This error has been resolved as of HyperSizer Version 5.3.31.

[HyperSizer User]

I've added a non-structural mass to the "Added Weight" check box on the FEM Interface options dialog.  Should this additional mass show up in the weight summary after running Hypersizer?

[Phil]

The entry of non-structural mass either imported from the finite element model or entered into the "added weight" field on the Options tab of the sizing form will not affect the weight results displayed in HyperSizer.  The weight results shown on the Sizing form or on the Summary tab of the Project Setup form reflect only the structural weight and do not include any added weight or non-structural mass.

The added weight included for a component WILL be reflected in the *.PM1 export of properties and materials for the next FEA iteration.