Deflagration-to-detonation transition process for spherical aluminum dust/epoxypropane mist/air mixtures in a large-scale experimental tube

Abstract

The deflagration-to-detonation transitions (DDTs) for clouds of spherical aluminum dust (SAD) mixed with air or epoxypropane mist (EPM) and air were investigated in a 29.6-m-long experimental tube of 199 mm in diameter. The clouds formed through the injection of SAD and SAD/liquid epoxypropane samples into the experimental tube. Explosions of the SAD/air mixture were initiated using a 7-m-long EPM/air cloud explosion ignited by a 40-J electric spark. Explosions in SAD/EPM/air clouds were initiated using a 1.2-m EPM/air cloud explosion ignited by a 40-J electric spark initiated using a 40-J electric spark. Self-sustained detonation waves formed in SAD/EPM/air mixtures instead of in SAD/air mixtures. The stages and characteristics of the DDT process in SAD/air and SAD/EPM/air mixtures were studied and analyzed. Self-sustained detonation was evident from the existence of a transverse wave and a cellular structure. Moreover, a retonation wave formed during the DDT process in SAD/EPM/air clouds. deflagration-to-detonation transition, spherical aluminum dust, epoxypropane mist, multiphase explosion, experimental tube

Effects of different product phases in aluminum dust detonation modeling

“…Zhang et al [5] investigated transverse waves in dusty detonations and calculated, using a detonation model, the minimum tube diameter for generating detonation. Flame acceleration and deflagration to detonation transition in the Al suspended mixtures have been studied experimentally [6][7][8]. Although the experimental results provide a research basis, information available from the experimental results is limited.…”