Laminar burning velocities of various silanes

In the present investigation, laminar burning velocities (LBVs) were measured for several different silane fuels (i.e., trichlorosilane, trimethylchlorosilane, methyldichlorosilane, dimethylchlorosilane, and tetramethylsilane) in order to evaluate their potential for vapour cloud explosions (VCEs). Laminar burning velocities were determined from constant-volume explosions in a closed vessel; the pressure rise of the initial portion of flame propagation was used to calculate the laminar burning velocity. The LBVs for the different silane compounds were found to be in the range of 43 cm/s (for dimethylchlorosilane) to 124 cm/s (for trichlorosilane). These values were then used to estimate blast effects of VCEs resulting from a 25,000 kg release of each fuel. In particular, the VCE severity of trichlorosilane was compared to that of propane and ethylene for a given release mass. It was found that a trichlorosilane VCE would produce greater overpressures than propane and ethylene in the near field but the pressure would decay more rapidly with increasing distance from the explosion centre. Moreover, the impulse from a trichlorosilane VCE would be considerably lower than that of propane and ethylene.