Inlet species fraction mismatch at low strain rates in counterflow diffusion flame

48 views
Skip to first unread message

Alexander Haake

unread,
Oct 1, 2025, 4:44:17 PMOct 1
to Cantera Users' Group

Hello everyone,


I’m trying to simulate a counterflow diffusion flame at low strain rates. When I reduce the mass flow rates, I notice that the computed species fractions near the inlets no longer match the specified boundary values.


This issue is reproducible with the “Scaling of diffusion flames with pressure and strain rate” tutorial by reducing the initial mass flow rates by a factor of 30.


Has anyone else observed this behavior? Could this be a bug in the solver or the boundary condition? And is there an easy workaround or fix?


Thanks and best regards,

Alexander


Cantera: 3.1.0 (stable)

Python: 3.10.12

OS: Ubuntu 20.04.5 LTS


diffusion_flame_batch_reducedMassflows.ipynb
diffusion_flame_batch_reducedMassflows.log

Ingmar Schoegl

unread,
Oct 25, 2025, 10:56:23 PM (3 days ago) Oct 25
to Cantera Users' Group
Hi Alexander,
What you’re observing is expected based on a mixed boundary condition, see
-ingmar-

Reply all
Reply to author
Forward
0 new messages