Mechanisms of prompt and delayed ignition and combustion of explosively dispersed aluminum powder

As a kind of high explosives, aluminized explosive cannot release the energy maximumly, which is a key problem. Using DTA-TG equipment, the ignition performance of three kinds of aluminized explosives (RDX, HMX, and CL-20) with different mass percentages of aluminum powder (0%, 10 wt.%, 20 wt.%, and 30 wt.%) was investigated. The results showed that the energy release of the HMX/Al composite explosive with 10 wt.%, 20 wt.%, and 30 wt.% aluminum powder was only equivalent to 80%, 65%, and 36% of pure HMX, respectively. It was similar to RDX/Al and CL-20/Al composite explosives, except the CL-20/Al mixture with 10% aluminum powder. Rather than participating in the ignition and combustion, the aluminum powder does effect the complete reaction of RDX, HMX, and CL-20 in the initial stage of ignition or in the lower temperature area of the boundary.

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Effects of Moisture Content on the Minimum Explosible Concentration of Aluminum Powder and the Related Mechanism

Journal of Energy ◽

10.1155/2020/1393891 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Haiyan Chen ◽

Qingguo Yao ◽

Qiqi Liu ◽

Hao Liu ◽

Xinyan Zhang

Keyword(s):

Moisture Content ◽

Aluminum Powder ◽

Combustion Process ◽

Dilution Effect ◽

Endothermic Effect ◽

Aluminum Powders ◽

Factors Affecting ◽

Ignition And Combustion ◽

Explosion Test ◽

Burn Rate

Aluminum powder has been widely applied to various industries. However, its high activity and high burn rate can cause serious explosion risks. Many factors affecting the explosion of aluminum powder have been determined, yet moisture content has not been included. In the present work, the minimum explosible concentrations of aluminum powders with different moisture contents were measured with a 20-liter explosion test apparatus using the explosion accident in Kunshan, China, as a study case. The experimental results suggest that the minimum explosible concentration of aluminum powder dramatically increases with the increase of its moisture content first and the increasing trend becomes slower as the moisture content further increased. The oxidation time has no significant effects on the minimum explosible concentration of aluminum power in 8 hours at room temperature. Further investigation suggests that the moisture lowers the explosion risk of aluminum powder by altering its surface oxide film, ignition, and combustion process. The low contents of moisture in the range of 0%-8% increase the minimum explosible concentration of aluminum powder by inhibiting the reaction kinetics and particle agglomeration, while high contents of moistures in the range of 8%-20% affect the minimum explosible concentration by the endothermic effect and oxygen dilution effect.

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Influence of operational parameters and design of the ejection nozzle on characteristics of finely dispersed aluminum powder: Part I. Influence of operational parameters of the nozzle

Russian Journal of Non-Ferrous Metals ◽

10.3103/s1067821216020036 ◽

2016 ◽

Vol 57 (2) ◽

pp. 131-134 ◽

Cited By ~ 1

Author(s):

V. A. Arkhipov ◽

M. Ya. Evsevleev ◽

I. K. Zharova ◽

A. S. Zhukov ◽

S. V. Zmanovskii ◽

...

Keyword(s):

Aluminum Powder ◽

Operational Parameters ◽

Powder Part ◽

Dispersed Aluminum

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The effects of additives on the combustion characteristics of aluminum powder in steam

RSC Advances ◽

10.1039/c6ra24911f ◽

2017 ◽

Vol 7 (10) ◽

pp. 5725-5732 ◽

Cited By ~ 11

Author(s):

Baozhong Zhu ◽

Fan Li ◽

Yunlan Sun ◽

Qichang Wang ◽

Yuxin Wu ◽

...

Keyword(s):

Ammonium Perchlorate ◽

Aluminum Powder ◽

Combustion Process ◽

Combustion Characteristics ◽

Ignition And Combustion ◽

Different Levels

To develop the combustion characteristics of aluminum powder in steam, the ignition and combustion process of aluminum powder with different additives (KBH4, ammonium perchlorate (AP) and NaCl) addition at different levels were studied using a transparent pipe furnace.

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