The promotion of nitromethane on solid–liquid fuel/air mixtures explosion characteristics under different ambient conditions

The explosion characteristics of nitromethane-epoxypropane-aluminum powder and nitromethane-n-pentane-aluminum powder fuel were studied in a 20 L explosion vessel under low-temperature, low pressure and high relative humidity conditions. The promotion of nitromethane on these solid–liquid fuel was exhibited based on the peak overpressure, (dp/dt) _max and their gas products detected by GC–MS. The results showed that nitromethane could play an effectively positive role in the solid–liquid fuel (epoxypropane/aluminum powder) under low-temperature or low-pressure conditions. However, this positive effect has only been observed in high-concentration (n-pentane/aluminum powder) fuels. Nitromethane can effectively reduce the impact of humidity on the fuel components and maintain a higher overpressure and (dp/dt) max when the relative humidity of less than 70% especially in high-concentration (nitromethane/-pentane/aluminum powder) group. In addition, it is difficult for nitromethane to make a more positive contribution with increasing humidity (70 ∼ 90%) because of the suppression of explosion by water vapor.