Inventor Nastran 2021.1 and 2021.1.1 list of changes

[John_Holtz]

Inventor Nastran 2021.1 and 2021.1.1 have been released and are now available to install. Use the Autodesk Desktop App (installed to the computer when any Autodesk software is installed) to install these updates. Note that Inventor Nastran 2021.0 needs to be installed before the update for 2021.1 is shown, and 2021.1 needs to be installed before the update for 2021.1.1 is shown.

This is my list of changes and explanation, taken from the What's New, Release Notes, and other issues addressed by development for the Inventor Nastran interface and the Nastran solver. (Unless noted otherwise, these changes are in version 2021.1.)

	Item
1	Added brittle failure material model (MATB) for the explicit analysis. This material needs to be added to the Nastran file manually; there is no interface in Inventor Nastran.
2	Added output request for applied load, contact forces, and plastic strain in an explicit analysis. These results can be viewed in the Nastran Editor Utility.
3	Explicit analysis is supported on current AMD processors. Prior to this, the analysis would fail. Also see Explicit solver analysis unable to solve in Nastran and Explicit Solver Known Issues 2021.1.
4	Added support for concentrated masses in an explicit analysis.
5	Added a new tutorial for the explicit analysis: Tutorial A8: Explicit Quasi-Static Analysis of a Copper Billet.
6	The terminology “Master” and “Slave” for surface contacts have been changed to “Primary” and “Secondary”.
7	When an analysis ends with an error, the runtime and Warning and Error Summary are now shown.
8	Corrected problem with contact stiffness for offset bonded contact when the model also included separation contact. See Linear stress results inaccurate when Nastran analysis includes offset bonded and separation contact...
9	Corrected a problem with S1117 during the analysis. See "FATAL ERROR S1117: INTERNAL ERROR DETECTED IN MODULE" in Nastran analysis (solver issue)
10	2021.1.1 Fixed issue with an Explicit  Quasi-Static analysis when it includes more than 1 step. See Fatal Error X7022 during quasi-static explicit analysis in Nastran.
11	(Added 2023 Aug 3) Fixed issue with Explicit Dynamics analysis. The mass added to a rigid material was not included. See Extra mass in a rigid material is not used in a Nastran explicit dynamics analysis.