Negative temperature
 

Hello ,

I am working on combustion of methane , where there are 50 species and 400 reactions . for initial solution i use non premix / partially mix pdf models and after wards i use edc models . but when i import my mechanism file and thermo file and enable the edc model and start the iterations

i get this sort of error on the very first iteration .




Error: ISAT reaction rate: Temperature = -7274.0K
Error Object: ()

Hello,

did you solve the problem? I'v pretty much the same, so it would be very nice to know how to handle it.

Thanks in advance!!

I've run into this problem while running a non-premixed turbulent combustion case...What I did was to set upper and lower limits for temperature closer to what my problem would present, in the Solution Controls tab. (In my case, I set the lower limit to 200K and the upper limit to something like 2500K, yours may differ of course). I did work in the end. :)

Thanks for your help Mike!
Unfortunately my problem seems to be a little more besetting... I set Temperature limits to 250 and 1600K but its still the same...

Primitive Error at Node 1: ISAT reaction rate: Temperature = -1248.0K

Anybody that had a similar problem and knows a solution?

much thanks in advance!!!

Hi,

I've encountered a similar problem where a heat source leads to negative temperatures in the system which is not physically sound. I also noticed that setting the lower temperature limit to say 300K does not limit the static temperature to 300K but the total temperature. Any further insights would be welcome.