Understanding the mechanisms of explosions is essential for the development of safety measured and for minimizing devastating hazards. Due to the complexity of real chemistry, a one-step reaction model has been often used for theoretical and numerical studies. In this paper we compare conditions for the detonation development from the spontaneous wave in a hot spot for a one-step model with that obtained for detailed chemical models. It is shown that for detailed chemical models conditions required for the detonation development from the spontaneous wave in a hot spot are more limited than that for the use of simplified chemical models. In particular, the minimum hot spot size capable of producing a detonation calculated with the detailed chemical model is at least an order of magnitude larger than that predicted by a one-step model even at high initial pressures. The impact of a detailed chemical model is particularly pronounced for the methane/air mixture, where not only is the hot spot size much greater than that predicted by a one-step model, but the initiation of detonation by the hot spot with a temperature gradient is possible only if the ambient temperature outside the gradient is above 1100 K.

International Seminar on Fire and Explosion Hazards (9; 2019; Saint Petersburg, Russia). Proceedings of the Ninth International Seminar on Fire and Explosion Hazards [Электронный ресурс]. Vol. 2: 21-26 April 2019, Saint Petersburg, Russia / Peter the Great St. Petersburg Polytechnic University, Autonomous Non-Profit Organization "Fire and Explosion Safety", Gefest Holding Ltd ; [edited by A. Snegirev [et al.]. — Электрон. текстовые дан. (1 файл : 98,7 Мб). — Saint Petersburg, 2019. — Загл. с титул. экрана. — Свободный доступ из сети Интернет (чтение, печать, копирование). — Adobe Acrobat Reader 7.0. — <URL:http://elib.spbstu.ru/dl/2/k19-97.pdf>. — <URL:http://doi.org/10.18720/SPBPU/2/k19-97>.