Characteristics and Mechanism of Slow Cook-off of Composite Explosive Charges
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摘要: 为研究不同结构复合装药在慢速烤燃过程中的响应规律,分别设计了JH-2和JHB炸药的
$\varnothing $ 19 mm单独药柱装药和$\varnothing $ 30 mm复合药柱装药烤燃弹,通过慢速烤燃试验分别获得了单独药柱烤燃弹在1和2 ℃·min−1升温速率、复合药柱烤燃弹在1 ℃·min−1升温速率下的温度-时间变化曲线,并结合数值模拟进一步分析了烤燃弹内部温度场的变化。研究结果表明:单独药柱装药情况下,低敏感炸药能明显降低弹药在热刺激下的响应等级;而在复合药柱装药时,烤燃弹响应点均位于外层低敏感药柱靠近壳体的环状区域,响应温度随高能药柱直径的增加而升高,响应等级随外层低敏感药柱厚度的增加而增加,复合装药由于药柱接触面存在接触热阻,烤燃弹传热受到阻滞,使得内部高能药柱极少参与反应。Abstract: In order to study the response law of composite charges with different structures in the process of slow cook-off, the cook-off bombs filled with$\varnothing $ 19 mm single charges of explosives JH-2 and JHB and$\varnothing $ 30 mm composite charges were designed. The temperature-time curves of single charges at 1 and 2 ℃·min−1and composite charges at 1 ℃·min−1 were obtained in tests, and combined with the numerical simulation to further analyzed the temperature field inside the bomb. The research results show that in the case of a single charge, the low-sensitive explosive can significantly reduce the response level of the bomb under thermal stimulation; while in the case of a composite charge, the response point of the bomb is located at the annular region of the outer low-sensitive charge near the shell. The response temperature increases with the increase of the high-energetic charge’s diameter, and the response level increases with the increase of the outer low-sensitive charge’s thickness. The heat transfer in the bomb is retarded due to the contact thermal resistance between the contact surface of composite charges, thus the inner high-energetic cylinder is rarely involved in the reaction.-
Key words:
- slow cook-off /
- composite charge /
- thermal contact resistance
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表 1 单一药柱慢速烤燃试验结果
Table 1. Slow cook-off test results of single charges
Explosive Heating rate/(℃·min−1) No. Temperature/℃ Response time/min JH-2 1 1 209.5 183.10 2 208.9 182.70 2 3 213.7 95.85 4 214.1 96.04 JHB 1 5 208.4 182.20 6 209.6 183.30 2 7 214.3 95.63 8 213.9 94.90 表 2 炸药与壳体的物性参数
Table 2. Physical parameters of explosives and shell
Material $\;\rho $/(g∙cm−3) c/(J∙kg−1∙K−1) $\lambda $/(W∙m−1∙K−1) RDX 1 640 1 130.00 0.250 TATB 1 938 1 170.00 0.544 Steel 8 030 502.48 43.000 表 3 炸药反应动力参数
Table 3. Reaction dynamic parameters of explosives
Explosive i E/(kJ∙mol−1) Z/s−1 Q/(MJ∙kg−1) RDX 1 194 6.40×1017 –2.68 2 185 4.74×1017 8.03 3 143 9.54×1014 65.60 TATB 4 252 7.02×1020 0.21 5 176 8.75×1012 0.21 6 142 4.36×1011 –2.94 表 4 单一药柱仿真结果与试验结果的比较
Table 4. Comparison between simulation and test results for single charges
Explosive Heating rate
/(℃·min−1)Response temperature/℃ Response time/min Calculate Test Calculate Test JH-2 1 206.60 209.2 179.75 182.9 2 214.68 213.9 93.92 96.0 JHB 1 207.68 209.0 180.83 182.8 2 214.18 214.1 93.67 95.2 表 5 复合药柱试验分组与组分药柱厚度
Table 5. Test group and charge thickness of composite charges
Charge species Thickness/mm G1 G2 G3 G4 G5 JH-2 14 15 16 17 19 JHB 16 15 14 13 11 -
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