This paper presents a study on the possibility of combustion waves in C{{H}₄} /air gas mixtures and heterogeneous dual-fuel mixtures (HDMs) C{{H}₄} /air/coal suspension with methane bulk concentration = 5- 8 % in a closed vertical shock tube and in a horizontal quartz tube open at one end. It has been shown that the value of the methane lower flammability limit (LFL) * and the flame stability depend on the channel location relative to the gravity vector and on the coal suspension concentration. In a vertical closed channel, combustion waves propagated from top to bottom in gas mixtures and HDMs at 6 %, whereas mixtures did not ignite at 5. 5 %. In a horizontal tube, flame propagated at 6 % in gas mixtures and at 5. 5 % in HDMs. Adding coal suspension to methane–air mixtures has little effect on the flame velocity, increases the flame brightness, and lowers the LFL.
Пинаев et al. (Wed,) studied this question.