Controlling low-pressure flame conditions by affecting the cold service lines located far from the heated reactor

A study was performed of a low-pressure oxyhydrogen flame in an isothermal regime in the diffusion-controlled region of heterogeneous chain termination. The chain propagation and termination sites were widely separated in space. Controlling the chain loss conditions made it possible to carry out isothermal combustion of the mixture in the diffusion-controlled region and to verify the proposition of the Semenov theory that the propagation of a chain explosion in time near the limit can be described by a linear model. From a comparison of calculated and experimental data, gas-surface interaction with a variable rate constant was found and the range of variation of this constant during one ignition was determined. The large differences between the kinetic curves obtained previously for various modes of chain termination on the wall were found to be related primarily to heterogeneous chain interaction, which governs the gas-phase process in the kinetic region and has a weak effect on this process in the diffusion-controlled region of chain termination. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 2, pp. 32–42, March–April, 2007.