Detonation Dampers for Ducts Transporting Gaseous Fuels

The very serious problem connected with long distance transport of gaseous fuels is connected with the fact that detonation may occur inside the duct if some air leaks into it. Detonation is particularly dangerous for compressors which “push” the gas through pipelines. It is therefore necessary to use some “detonation dampers” to protect these compressors. The commonly used detonation damper has a form of a matrix of narrow channels, placed across the pipe transporting gas. Detonation wave is supposed to be extinguished due to cooling by cold walls of these channels. To achieve efficient damping the channels should be very narrow. Our earlier simulations (Walenta et al. in Central European Journal of Energetic Materials. 1:49–59, 2004; Walenta Z.A., Slowicka A.M.: Extinguishing detonation in pipelines—optimization of the process, In: K. Kontis (ed.), Proceedings of 22nd Int. Shock Interaction Symposium, Glasgow, pp. 202–206. (2016).; Walenta Z.A., Slowicka A.M.: Detonation Waves in Narrow Channels of Various Shapes, Proceedings of 23rd Int. Shock Interaction Symposium, Skukuza, Kruger National Park, South Africa, pp. 135–140 (2018).) indicate, that preferable widths should be of the order of 0.005 mm. This is not acceptable for practical reasons—in real applications it is close to 0.5 mm. In such channels cooling the gas by heat transfer is inefficient and cannot extinguish the flame (cooling effect is proportional to perimeter of the channel cross-section and amount of gas to be cooled to cross-section surface). Rarefaction wave generated behind sharp increase of channel cross-section is an alternative phenomenon, which may be used to cool the burning gas (Walenta et al. in Central European Journal of Energetic Materials. 1:49–59, 2004). In our earlier papers we tested several channel shapes with increase of cross-section (Walenta Z.A., Slowicka A.M.: Extinguishing detonation in pipelines—optimization of the process, In: K. Kontis (ed.), Proceedings of 22nd Int. Shock Interaction Symposium, Glasgow, pp. 202–206. (2016).; Walenta Z.A., Slowicka A.M.: Detonation Waves in Narrow Channels of Various Shapes, Proceedings of 23rd Int. Shock Interaction Symposium, Skukuza, Kruger National Park, South Africa, pp. 135–140 (2018).). Here we compare channels 0.5 mm wide, without and with sharp increases and decreases of cross-section. Such channels were found to be the best for practical applications.