chemkinToFoam handling units properly?

m_a_s · July 8, 2021, 14:27

Greetings OF users.

I needed to convert a Chemkin mechanism for use in OF. I tried using the chemkinToFoam converter, but some of the values in the generated OF reactions file seem suspicious.

Consider the following Chemkin reaction line:

OH+H2=H+O2 2.14E+08 1.52 3449.0

The A, beta, and Ta values were converted to 214000, 1.52, and 1735.506583, respectively. Since there were not any unit callouts in the Chemkin file, the 3rd term (the activation energy) should have been in cal/mol (1 cal = 4.184 J) but the value is scaled by a factor of 1.987.

Am I missing something?

m_a_s · July 9, 2021, 12:58

I think I figured it out. The factor is 4.184/R (R=8.314J/(mol*K)) which gives me the same number 1735.50...

July 8, 2021, 14:27	chemkinToFoam handling units properly?	#1
m_a_s New Member Mark Join Date: Jun 2017 Posts: 4 Rep Power: 9	Greetings OF users. I needed to convert a Chemkin mechanism for use in OF. I tried using the chemkinToFoam converter, but some of the values in the generated OF reactions file seem suspicious. Consider the following Chemkin reaction line: OH+H2=H+O2 2.14E+08 1.52 3449.0 The A, beta, and Ta values were converted to 214000, 1.52, and 1735.506583, respectively. Since there were not any unit callouts in the Chemkin file, the 3rd term (the activation energy) should have been in cal/mol (1 cal = 4.184 J) but the value is scaled by a factor of 1.987. Am I missing something?

July 9, 2021, 12:58		#2
m_a_s New Member Mark Join Date: Jun 2017 Posts: 4 Rep Power: 9	I think I figured it out. The factor is 4.184/R (R=8.314J/(mol*K)) which gives me the same number 1735.50... Amirreza_pro likes this.

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