Hydrogen-Air Reaction Mechanism (CHEMKIN II/III)

In this sample, the reaction mechanism from the CHEMKIN II/III manual example [1] is used. This mechanism includes 23 reactions with 11 species. A fixed pressure problem is solved


Input values

Pressure: 1atm
Temperature: 1000K
Gas mixture: [H2]0 : [O2]0 : [N2 ]0= 1 : 3 : 0.1


Solution

The results from CHEMKIN and this solution are presented in Table 1 for two time points 3.0E-05 and 3.0E-04 sec. The three significant digits of the solutions coincide.


Table 1. Mole fractions and temperature vs. time

Species

H2

O2

OH

H2O

H

O

3.E-05 sec

2.44E-01

7.32E-01

1.44E-06

2.59R-05

8.17E-06

4.25E-06

3.E-04 sec

1.79E-03

6.72E-01

3.07E-02

2.56E-01

1.03E-03

1.15E-02

1 sec

1.72E-03

6.69E-01

2.98E-02

2.57E-01

9.61E-03

1.08E-02

Species

HO2

H2O2

N2

NO

N

T(K)

3.E-05 sec

1.29E-05

1.03E-08

2.44E-02

3.75E-20

1.81E-21

1.00E+03

3.E-04 sec

6.00E-05

1.52E-06

2.73E-02

2.17E-05

2.41E-09

2.49E+03

1 sec

5.84E-05

1.48E-06

2.37E-02

7.26E-03

3.82E-08

2.48 E+03

 

 
Fig 1. Comparison of calculated profiles: points – CHEMKIN data [1], lines – Chemked calculation.


The same reaction mechanism and initial conditions are used for checking calculation of gas parameters in equilibrium region. In this case the problem must be solved to a long final time (for example, to 1 sec) to make sure that the equilibrium is established. The species mole fractions of the equilibrium region are presented in Table 1. These data are excellently coincident with equilibrium gas composition obtained independently with the CHEMKIN Equil program.


References

[1] R.J. Kee, F.M. Rupley, J.A. Miller, M.E. Coltrin, J.F. Grcar, E. Meeks, H.K. Moffat, A.E. Lutz, G. Dixon-Lewis, M.D. Smooke, J. Warnatz, G.H. Evans, R.S. Larson, R.E. Mitchell, L.R. Petzold, W.C. Reynolds, M. Caracotsios, W.E. Stewart, P. Glarborg, C. Wang, and O. Adigun, CHEMKIN Collection, Release 3.6, Reaction Design, Inc., San Diego, CA (2000).