Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Error in some cases

Please login with a confirmed email address before reporting spam

I have modeled a chanel of a monolithic reactor which has a thin layer of catalyst on the chanel wall.a mixture of ideal gases flows through the reactor.I have defined three physics:transport of concentrated species,laminar flow and heat transfer of solids and fluids.I also coupled them with these two multiphysics:nonisotherm flow and reacting flow.viscosity,thermal conductivity,diffusion coefficiens ,etc are temperature dependent.the problem is that in some inlet velocities the model can be solved but in a specific range doesn’t converge or shows me some errors about the variables (temperature dependent properties),even when I set them as constant parameters.in addition, I can predict that it is because of the sharp temperature changes in the mentioned velocities. Generally , I think the model is temperature sensitive because I’ve been modeling an isothermal model successfully.maybe it’s all about mesh but I have tried deferent meshes.l don’t know how to fix this.Is there anyone who can assist me in this urgent case?


2 Replies Last Post 30 dic 2020, 07:34 GMT-5

Please login with a confirmed email address before reporting spam

Posted: 4 years ago 29 dic 2020, 02:38 GMT-5

A general comment: make an auxiliary sweep of a parameter, in this case the velocity, i.e. increase it gradually to the desired value. Usually it helps.

BR Lasse

A general comment: make an auxiliary sweep of a parameter, in this case the velocity, i.e. increase it gradually to the desired value. Usually it helps. BR Lasse

Please login with a confirmed email address before reporting spam

Posted: 4 years ago 30 dic 2020, 07:34 GMT-5

A general comment: make an auxiliary sweep of a parameter, in this case the velocity, i.e. increase it gradually to the desired value. Usually it helps.

BR Lasse

thank you for your idea. I tried it but it didn't help!

>A general comment: make an auxiliary sweep of a parameter, in this case the velocity, i.e. increase it gradually to the desired value. Usually it helps. > >BR >Lasse thank you for your idea. I tried it but it didn't help!

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.