divergence in AMG:enthalpy

ernie

Dear All,

I'm working on fixed bed gasifier, steady state. fuel inlet from the top, air from the bottom of combustor while the product gas leaves from the top also.

I used prePDF to define non-premixed. i model the solid fuel using group injection.

After some iteration, a message appeared" error: divergence in AMG solver: enthalpy". How to fix this problem and how does this actually happen?

I would like to hear any advice and suggestion from you,

Thank you

Regards, Ernie