Limitations (may coexist, but out of the selected AMS part group)

CAUTION:

/PARITH/ON is not yet insured with AMS, if the number of domains changes. But, for one same domain number, results are same whatever the number of threads.

SPH: AMS does not increase time step of SPH (example: tank sloshing in crash)
ALE - Euler - FVM: formulations are not supported (but can be put out of /AMS part, if time step is decent)
2D analysis: /AMS is not available
Parts involving:
- Lagrange multipliers: /MPC and /GJOINT
- /FXBODY

In such cases, a warning is output by Radioss Engine and the computation may even diverge.

Elements:
- 4-node tetra: /TETRA4 with I_tetra4=1 or 3
- 10-nodes tetra: /TETRA10 with I_tetra10=2
- 16-node shell: /SHEL16
- 20-node bricks: /BRIC20
- Multi-strand: /XELEM

In such cases, the computation will most likely diverge.

Rigid bodies cannot be activated and deactivated with sensors
Interfaces: /DT/INTER/CST is not compatible with /DT/AMS
- Nodes that are secondary of both: a tied interface TYPE2 and a contact interface (TYPE7 or TYPE11) will have their contact stiffness removed. A Starter message in the 0.out file is then issued:
```
** WARNING SECONDARY NODE OF AN INTERFACE TYPE2 & AMS
  INTERFACE TYPE[7 or 11], ID=xxxxxx:
  SECONDARY NODE ID=yyyyyyy IS ALSO SECONDARY NODE OF AN INTERFACE TYPE2
 THE NODE CONTACT STIFFNESS WILL BE DE-ACTIVATED CASE OF /DT/AMS
```
  This contact deactivation can be avoided by using Spot_flag=25, 27 or 28 (TYPE2 penalty formulation).
- Kinematic formulation (TYPE2) for spotwelds may alter AMS performance when there are many spotwelds, particularly hexa spotwelds.
Airbags with reference metrics: /REFSTA or /XREF do not benefit from AMS speedup.
Refer to the Starter Input and Engine Input Reference Guides.

Table 1. Main Advanced Mass Scaling Limitation Summary
	Elementary time step for AMS /DT/AMS in Radioss Engine Input
Lagrange Multipliers	Does not work
16-node thick shells and 20-node bricks	Free element time step is applied to these elements
Rigid bodies activated, deactivated with sensors	Does not work
Interfaces	Only TYPE2, TYPE7, TYPE10, TYPE11, TYPE19, TYPE20, TYPE21, TYPE24, and TYPE25 are supported