Hello!

I am trying to model a channel (0.5 mm x 1 mm x 50 mm; mesh 5x10x100) with 4 surface reactions at bottom of the channel.

The kinetics of the reactions are written with UDF. For 2 reactions of them I use "for loops" i.e. iteration, considering of the effects of another variables.

Although my model is not complicated at all, the calculation takes such a long time. As I checked, the iteration in UDF itself does not take long.

Since 2 months I work with new version 6.3.26 and I get a notion, that the calculation is slower than the prior version (6.2.16). Can it be a reason for it?

How can I speed up my calculation?

Regards

run parallel

please advise which line is the error from?