Understanding, Troubleshooting, and Overcoming Mesh & DOF Constraints in Ansys Simulations
fluent 3ddp -g -t4 -i journal.jou Or for Mechanical: In CFX, you can run the solver separately
Have you encountered this warning with a specific license type? Leave a comment below or contact your Ansys support channel for size limit exceptions. Purchase or Rent a “Problem Size Unlocked” Token
If you are a simulation engineer, you have likely encountered the dreaded pop-up or output message while solving a model in Ansys Fluent, Mechanical, or HFSS: “Your product license has numerical problem size limits verified” or a variation such as “License limits restrict the maximum problem size (number of nodes/cells).” but avoids GUI overhead).
ansysXX -dis -b -m 4 -i input.dat -o output.out The batch flag ( -b ) sometimes bypasses immediate size verification (not a full bypass, but avoids GUI overhead). In CFX, you can run the solver separately from the pre-processor. The license check occurs at solver start—using a different feature set may allow larger sizes. 6. Purchase or Rent a “Problem Size Unlocked” Token Contact your Ansys reseller to add a “Max Problem Size Unlimited” add-on or upgrade your license from Professional to Enterprise. For temporary needs, consider elastic licensing (ELU) to rent high-tier tokens for 24 hours. 7. Optimize Using HPC Packs (For MPI Solves) If you have many cores but a capped license, distributing across nodes might trigger the limit earlier. Run serial (1 core) first to see if it’s a true node limit or a parallel licensing issue. Sometimes reducing cores to 2 avoids an HPC pack requirement that inadvertently enforces problem size checks. Part 6: Preventing the Error in Future Projects Proactive engineering is better than reactive debugging. Best Practice 1: Run a “License Check” Pre-Solve Script Add a small Python script in Workbench that queries: