Procad Blog - Keep up to date with all the latest news and events

Rachel McNamara 08



Nastran Parallel Processing Capability

How to check the number of Cores in your processor?

Step 1:  Press Ctrl + Shift + Esc to open Task Manager.

Step 2:  Select the Performance tab to see how many cores and logical processors your PC has.

CPU Performance

Nastran Parallel processing capability

The Nastran solvers do use multiple processors. The only thing that you need to do is indicate how many processors you want to use. (The default is 2, which is why the log file indicates the analysis is using only 2 of your available processors.) You want to set the value for the Parameter NPROCESSORS.

How to change the number of processors to be used by Nastran?

Step 1: Go to Nastran-In-Cad environment


Step 2: In the Nastran Model Tree, go to Parameters.


Step 3: Open the Parameters tab.

Parameters Tab

Step 4: Go to Parameters > Program Control Directives.

Step 5: From here we can change the Number of Processors to be used for the analyses by changing the value of NPROCESSORS. The default value for NPROCESSORS is 2 and can be changed to the number of cores your PC has.


Please Note: This setting will only be applicable for this Analysis only and won’t continue for the future analysis. The default setting for the number of processors will be restored, i.e. 2, once the Nastran solver is restarted.

Also, bare in mind that meshing is not included in this edit as it will only work on the solver side. 

You will see development for some models while others will show only minor improvement in pace.

How can the default parameters for all new Nastran In-CAD analyses (version 2019.2 and older) or Inventor Nastran analyses (version 2020.0 and newer) be changed so that one does not have to manually define settings for each new analysis?


To modify the default parameters for all future analyses, modify the file NASTRAN.INI. This file is located in the installation folder:

  • For 2015-2018, the default installation folder is "C:\Program Files\Autodesk\Nastran In-CAD YYYY\System\Nastran\Nastran.INI", where "YYYY" is the year.
  • For 2019, the default installation folder is "C:\Program Files\Autodesk\Nastran 2019\Nastran".
  • For 2020 and newer, the default installation folder is "C:\Program Files\Autodesk\Inventor Nastran YYYY\Nastran".
  • Otherwise, search for NASTRAN.INI.

The file can be modified using any standard text editor such as Notepad.

Note: Windows 10 may not let the user save the NASTRAN.INI file to the default location. If this occurs, save the file to a different folder. Then move the file to the default folder and give permission to replace it.


Need further assistance with the Nastran Parrallel Processing capability or want to speak with one of our Specialists, contact us by clicking below!
New Call-to-action

Tags: Nastran In-CAD, Autodesk Products, Autodesk Solutions

Share this article:

Recent Posts



Tag Cloud

see all

Subscribe to Email Updates