This section contains information about feature enhancements that can affect program behavior or analysis results in ways that you may not expect. Also covered are known incompatibilities, notable issues and defects that have been resolved, and information about replacement capabilities for features that have been removed.
The following topics offer supplemental 2025 R1 product-update information presented by the Mechanical APDL development and testing teams:
If you are upgrading across several releases, you may find it helpful to consult the Update Guide sections of the archived release notes for Mechanical APDL.
For information about past, present, and future operating system support, see the Platform Support section of the Ansys Website.
Mechanical APDL Release 2025 R1 can read database files from all prior Mechanical APDL releases. Due to ongoing product improvements and defect resolutions, however, results obtained from old databases running in new releases may differ somewhat from those obtained previously.
The following Mechanical APDL feature updates in Release 2025 R1 are known to produce program behaviors or analysis results that differ from those of the prior release:
9.2.1. Change in Level of Difficulty Values for the PCGOPT Command
The level of difficulty argument for the PCGOPT command
(PCGOPT,Lev_Diff) values have
been changed to more granular options. Therefore, the
Lev_Diff values from former releases now have new
meanings, as mapped in the table below. You must ensure your
Lev_Diff values correspond to their new
meanings.
Previous
Lev_Diff
Behavior | Current
Lev_Diff
Behavior | Current
Lev_Diff Values Compared to
Previous Behavior Values |
AUTO — Automatically chooses
Lev_Diff value (1 through
4) | AUTO — Automatically chooses
Lev_Diff value (1 through
5) | |
| 1 | 1 | Smaller than previous level 2 |
| 2 | 2 | Smaller than previous level 2 |
| 3 | 3 | Previous level 2 |
| 4 | 4 | Close to previous level 3 |
| 5 | 5 | Close to previous level 4 |
The CUDA libraries have been updated to version 12.6, which only supports Visual Studio 2022 Professional. Therefore, the version used in prior releases (Visual Studio 2019 Professional) is no longer supported.
The following issues are known to exist at Release 2025 R1:
The program ignores
LAYERandSHELLinput on the NLHIST command. — TheLAYERandSHELLarguments on the NLHIST command have no impact on the NLHIST command output. For layered structural and thermal elements, the first set of the layered element nodal data (ESOL) is always selected for tracking during solution.Models running on AMD GPU devices while using the PCG solver may crash — Crashes due to missing ROCm packages may occur when running on AMD GPU devices while using the PCG solver. The error message contains some or all of the following:
Memory access fault by GPU node-2 (Agent handle: 0x18c9150) on address 0x14f319185000. Reason: Page not present or supervisor privilege. GPU core dump failed forrtl: error (76): Abort trap signal Image PC Routine Line Source libc.so.6 000014F4E7C54DB0 Unknown Unknown Unknown libc.so.6 000014F4E7CA154C Unknown Unknown Unknown libc.so.6 000014F4E7C54D06 raise Unknown Unknown libc.so.6 000014F4E7C287F3 abort Unknown Unknown libhsa-runtime64. 000014F4E5475327 Unknown Unknown Unknown libhsa-runtime64. 000014F4E5474434 Unknown Unknown Unknown libhsa-runtime64. 000014F4E5427677 Unknown Unknown Unknown libc.so.6 000014F4E7C9F802 Unknown Unknown Unknown libc.so.6 000014F4E7C3F450 Unknown Unknown Unknown
Workaround: A potential fix to this issue is installing the latest complete ROCm package from AMD.
Open MPI with AMD machines limitation — When using Open MPI, running Mechanical APDL in a nested manner is not supported. Example:
/syp, /ansys_inc/v251/ansys/bin/mapdl -j sample_test
Inconsistencies in the Extended Drucker-Prager (EDP) Cap Creep model — An analysis using the Extended Drucker Prager Cap Creep model (TB,EDP,,,,CYFUN + TB,CREEP) may produce incorrect results, if any of the following conditions apply:
You have specified time-dependent creep law parameters such that creep strain depends on time. In this case, the program incorrectly passes a zero current time value to the creep routines. Typically, this leads to a stress calculation that does not converge, and a warning message appears. However, if the stress calculation converges, the results may be incorrect. The following creep models (TB,CREEP,,,,TBOPT) are affected:
TBOPT= 2: Time HardeningTBOPT= 3: Generalized ExponentialTBOPT= 4: Generalized GrahamTBOPT= 5: Generalized BlackburnTBOPT= 6: Modified Time HardeningTBOPT= 11: Combined Time HardeningTBOPT= 12: Rational PolynomialTBOPT= 13: Generalized Time HardeningTBOPT= 100: User Creep
You have issued RATE,OFF to disable the creep strain rate. The EDP Cap Creep routines ignore this command, and the creep strains continue to evolve according to the creep law and its defined parameters.
You have implemented user-defined state variables (TB,STATE) in combination with the user-defined creep model (TB,CREEP,,,,100). In this case, the program forwards incorrect user-defined state variables to the
UserCreeproutine as subroutine argumentsnstatvandUstatev.You have specified the field variable dependency (TBTEMP or TBFIELD) for the EPD Cap yield function parameters (TB,EDP,,,,CYFUN). In this case, the program ignores the field variable dependency in the update of the yield surface parameters sigma_c (cohesion), K0 (intersection between compression cap and shear envelope) and X0 (compression cap yield pressure) when inelastic strains (plastic strain + creep strain) occur.
Inconsistency in the Extended Drucker-Prager (EDP) Creep model with UserCreep — An analysis using the Extended Drucker Prager Creep model with UserCreep (TB,EDP + TB,CREEP,,,,100) may produce incorrect results, if user-defined state variables (TB,STATE) are used. In this case, the program forwards incorrect user-defined state variables to the
UserCreeproutine as subroutine argumentsnstatvandUstatev.
For issues discovered following publication of this document, see Mechanical APDL in the Ansys Known Issues and Limitations.
The following notable issues and defects for Mechanical APDL have been resolved at Release 2025 R1:
| ID | Resolution Description |
|---|---|
| 1100522 | The licenses for SEXP and SEEXP are now correct. SEXP is available to all license levels. SEEXP is available for the Enterprise license. |
| 1022147 | BINLIB not supporting Unicode (non-ASCII) characters has been documented. For more information, see Accessing Binary Data Files in the Programmer's Reference. |
| 1023052 |
The instability when using the Open MPI library and clusters containing AMD architecture with a high core count has been documented with a workaround. For more information, see Troubleshooting in the Parallel Processing Guide. |
If a legacy Mechanical APDL feature has been removed at Release 2025 R1, this section provides information about the Mechanical APDL replacement feature, its functional equivalent in another Ansys product, or another workaround.
Legacy features that have been archived also appear here. While archived features remain available for use, technical enhancement is unlikely to occur, and better alternatives are available and recommended in most cases.
The following topics are available:
The ICCG and QMR solvers have been archived, along with parts of the JCG solver that do not support DMP. For more information, see Iterative Solvers in the Feature Archive.