Potential accelerating effect of thermal radiation in dust flame propagation : some experimental evidence

International audienceThe role of thermal radiation in premixed flame propagation has been a matter of debate for decades. And it is not only a challenging scientific point, it has significant practical implications. For instance, a route to explain the Buncefield explosion ([4]) was the implication of tiny particles raised by the blast and promoting flame acceleration through enhanced heat exchanges by thermal radiation in the flame front. In dust explosion protection, the flame is implicitly supposed to propagate like a in a gaseous mixtures but if thermal radiation is dominant for some dusts, many aspects concerning the way to mitigate the explosions for those particular dusts would need to be revised ([7]). A review of the various aspect linked to this question was proposed recently ([2]) suggesting in particular that aluminium dust flames could be subject to heat radiation dominated flame propagation regimes. A very similar point was made for the specific case of premixed gases seeded with particles ([5]). But to date, experimental evidence is severely lacking. It is intended to provide in this communication, preliminary experimental evidence of the potential promoting role of thermal radiation is dust flame propagation