Error: ISAT reaction rate

Basy · December 12, 2011, 04:26

Hi
I am trying to simulate combustion with Steady Laminar Flamelet model (Non-premixed model in fluent). I did it with some mechanisms like GRI3.0 with no problem. but for some other reaction mechanisms I face this problem:
I read the mechanism in CHEMKIN format into Fluent and when I want to develop the flamelet, I get this error:

Error: ISAT reaction rate: Temperature = -3325385810.5K
Error Object: ()

I can bypass this problem by changing the relative error tolerance in Integration control form e-10 to e-17 but the accuracy of result is lowered and it seems I am just getting some "Garbage in/Garbage out". does any one have an idea about the source of problem?

thank you in advance for sharing your thoughts.
behzad

rezareal · April 22, 2013, 06:59

Hi Behzad
if you obtain answer your question,please guide me
thanks

Basy · April 22, 2013, 07:17

Unfortunately I couldn't solve the problem...

December 12, 2011, 04:26	Error: ISAT reaction rate	#1
Basy New Member behzad Join Date: Oct 2010 Location: Technical University of Malaysia(UTM) Posts: 14 Rep Power: 16	Hi I am trying to simulate combustion with Steady Laminar Flamelet model (Non-premixed model in fluent). I did it with some mechanisms like GRI3.0 with no problem. but for some other reaction mechanisms I face this problem: I read the mechanism in CHEMKIN format into Fluent and when I want to develop the flamelet, I get this error: Error: ISAT reaction rate: Temperature = -3325385810.5K Error Object: () I can bypass this problem by changing the relative error tolerance in Integration control form e-10 to e-17 but the accuracy of result is lowered and it seems I am just getting some "Garbage in/Garbage out". does any one have an idea about the source of problem? thank you in advance for sharing your thoughts. behzad

April 22, 2013, 06:59	Isat Error	#2
rezareal New Member reza Join Date: Feb 2012 Posts: 2 Rep Power: 0	Hi Behzad if you obtain answer your question,please guide me thanks

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April 22, 2013, 07:17		#3
Basy New Member behzad Join Date: Oct 2010 Location: Technical University of Malaysia(UTM) Posts: 14 Rep Power: 16	Unfortunately I couldn't solve the problem...