Effect of initial temperature on the explosion pressure of various liquid fuels and their blends

Abstract In this work, the effect of initial temperature on the explosion pressure, P ex , of various liquid fuels (isooctane, toluene and methanol) and their blends (isooctane-toluene and methanol-toluene, with three different fuel-fuel ratios) was investigated by performing experiments in a 20-l sphere at different concentrations of vaporized fuel in air. The initial temperature was varied from 333 K to 413 K. Results show that, as the fuel-air equivalence ratio, Φ, is increased, a transition occurs from a “thermodynamics-driven” explosion regime to a “radiant heat losses-driven” explosion regime. The maximum pressure, P max , is found in the former regime (Φ  ex with increasing initial temperature. This trend has been explained by thermodynamics. In the latter regime (Φ > 3), P ex increases with increasing initial temperature. This trend has been addressed to the decrease in emissivity (and, thus, radiant heat losses) with the increase in temperature.