Numerical simulation of ignition of a hydrogen-oxygen mixture in view of electronically excited components

On the role of excited species in hydrogen combustion

“…Reactions comprising updated hydrogen combustion mechanism as well as ozone decomposition reactions and associated rate constants have been discussed recently [34,40], therefore they are only mentioned here if alternative product channels were proposed in in the most recent models of Starik et al [13,32], of Popov [5,29], and in the MSU mechanism [25,30]. The numbering of the reactions included in the present mechanism corresponds to Table 1, while reactions excluded from the model are listed in Table 2 with numbers (X1), (X2), etc.…”

“…Chukalovsky et al [5] compared the MSU (Moscow State University) mechanism [25,30], the mechanisms developed by Starik and Titova in 2003 [19], by Starik et al in 2010 [13], and updated mechanism based on the works of Popov [27][28][29]. They found that at the conditions of experimental study of Smirnov et al [3], the most important initiation reaction is…”

“…It was demonstrated [34] that due to the incompleteness of the MSU mechanism (absence of many reverse reactions) it predicts an incorrect balance between O atoms, excited and ground state oxygen in ozone flames. It should be noted, however, that ozone reactions from the MSU mechanism [25,30] excluding excited oxygen species are mostly balanced, and their implementation in the recent studies of combustion enhancement by ozone [6,[35][36][37][38][39] is justified. Yet, conclusions based on the complete set of reactions taken from the MSU mechanism by Ombrello et al [7], and by Bourig et al [26], should be treated cautiously.…”

“…Reactions pertinent to excited singlet states of oxygen and ozone implemented in the most recent models of Starik et al [13,32], of Popov [5,29], and in the MSU mechanism [25,30] are most often inconsistent and largely different in rate constants as well. The inconsistency is manifested in the irreversibility of many reactions with excited species.…”

“…Furthermore, direct current low pressure glow discharge was shown to substantially reduce induction length of the H 2 + O 2 mixture ignition in a flow reactor [3]. This experiment was simulated using one-dimensional [4] and 2D models [5] with the development by addition of ozone [24], decrease of ignition delays [25][26][27][28][29], and increase of the burning velocities in hydrogen + air mixtures [26].…”