Float overflow at des/sq_rotation.f:624 running SQP simulation

[majidkhalil]

Dear Expert!
During DEM-SQP sim following error occurs.

Guide me to resolve that problem.
Thanks.
1000p.mfx (16.4 KB)

[cgw]

As we have been seeing, the SQP code tends to produce extremely large numbers when checking for collisions, and it may not be possible to prevent overflows in all cases. Although we generally use IEEE754 behavior to trap floating point exceptions (FPE), this may be one of those cases where it is in fact more appropriate to disable FPE trapping and allow IEEE +/-Inf values.

The next version of MFiX (23.2) will give more fine-grained control over overflow behavior. In the meanwhile I suggest you disable ALL FPE traps as described here:

Float overflow at des/cfnewvalues.f:539 running SQP simulation

Please use a more descriptive topic title so that other users may search the forum for answers. Instead of “MFiX Solver crashed” something like “Float overflow in DEM-SQP case” (I modified the topic title already) As we have been learning (see the SQP Megathread), the superquadric code tends to produce extremely large numeric values, often leading to overflows. This, I believe, is largely due to “overshoots” in the Newton-Raphson successive-approximation scheme used to detect particle-p…