An Algorithm for Allocation and Temperature, and Its Consequences for the Chemistry of H₂-O₂ Combustion

Abstract

We will outline a non numerical algorithm for calculation of chemical species in the burned gas, temperature increase, and overall chemistries for plane premixed laminar flames with arbitrarily complex chemistry. We will then apply this algorithm to H2-O2 combustion between 1100° and 1600°, using reaction data from Westbrook and Chase [1]. We will study the system

$$ \begin{gathered} {1}.{\text{ H }} + { }{{\text{O}}_{{2}}} = {\text{ O }} + {\text{ OH}}, \hfill \\ {2}.{\text{ O }} + { }{{\text{H}}_{{2}}} = {\text{ H }} + {\text{ OH}}, \hfill \\ {3}.{ }{{\text{H}}_{{2}}}{\text{O }} + {\text{ H }} = { }{{\text{H}}_{{2}}} + {\text{ OH,}} \hfill \\ {4}.{\text{ O }} + { }{{\text{H}}_{{2}}}{\text{O }} = {\text{ OH }} + {\text{ OH}}, \hfill \\ {5}.{ }{{\text{H}}_{{2}}} + {\text{ M }} = {\text{ H }} + {\text{ H }} + {\text{ M}}, \hfill \\ {6}.{ }{{\text{O}}_{{2}}} + {\text{ M }} = {\text{ O }} + {\text{ O }} + {\text{ M}}, \hfill \\ {7}.{\text{ OH}} + {\text{M }} = {\text{ O }} + {\text{ H }} + {\text{ M}}, \hfill \\ {8}.{ }{{\text{H}}_{{2}}}{\text{O }} + {\text{ M }} = {\text{ H }} + {\text{ OH }} + {\text{ M}}, \hfill \\ \end{gathered} $$

((1.1))

where M denotes a chaperone species. For convenience, we will refer to reaction i in the forward direction as Ri+ and define Ri- similarly. Rl+ competes directly with the reaction H + O₂ + M = HO₂ + M, and is faster when T>1100°, so we can assume (Westbrook and Dryer, [2]) that H₂O₂ and HO₂ will not be present in significant amounts. We assume that the only input species that are not inert are H₂ and O₂.