High-Speed Two-Dimensional Measurements of Flame Propagation Velocity and Temperature Distribution of TiH2 Dust Flame

In order to explore the application feasibility of hydrogen storage alloy TiH2 in thermobaric bombs, an open and a semi鄄open Hartmann tube were used to simulate the explosion processes of a thermobaric bomb in the air and underground tunnels, respectively. By using the two鄄dimensional high鄄speed measurement platform on basis of the colorimetric thermometry and contour detection methods, flame characteristic parameters and influencing factors of TiH2 dust cloud with different concentrations were studied. The experimental results showed that: in the open space, the flame temperature of TiH2 dust was in the range of 2 150 - 2 400 K, and the flame temperature decreased with the increase of dust concentration; the flame propagation velocity and acceleration were not affected by the dust concentration in the early stage, but increased with the increasing dust concentration in the later stage; in the confined space of a pipeline, the temperature of dust clouds with different concentrations of TiH2 during stable combustion were around 2 430 K, and the higher the dust concentration, the shorter the flame propagation time to the top; the stable flame temperature of dust clouds in the pipeline was 50 - 210 K higher than that in the open space, and the flame propagation velocity was 6 - 15 times than that in the open space. Compared with the traditional explosion testing methods, the colorimetric thermometry method can precisely measure the transient temperature distribution of a certain zone, and the contour detection method can accurately measure the propagation velocity and acceleration of flame front surface, which may provide a new technical means for the formulation design and damage effectiveness evaluation of thermobaric bombs. © 2023 China Ordnance Society. All rights reserved.