强约束固体炸药燃烧裂纹网络反应演化模型

Burning-crack Networks Model for Combustion Reaction Growth of Solid Explosives with Strong Confinement

为表征受约束装药非冲击点火后的反应演化行为,建立了燃烧裂纹网络反应演化理论模型。该模型量化了反应烈度,通过与实验结果对比验证了模型的适应性。结果表明:壳体约束越强,高温产物气体自增强燃烧越迅速,装药反应越剧烈,壳体破坏时装药反应度越大;装药结构尺寸越大,炸药反应初期高温产物气体流动和表面燃烧导致裂纹增压扩展过程的时间越长,但后期反应越剧烈,壳体破坏时装药反应度越大;点火阈值压力对装药最终的反应烈度影响不明显。炸药燃烧裂纹网络反应演化模型可较好地反映炸药本征燃烧速率、约束强度、装药结构尺寸等对反应演化的影响规律,为弹药在意外刺激下的安全性设计和烈度量化评估提供了理论基础。

A theoretical model for burning-crack networks is developed to characterize the non-shock initiation reaction growth behavior of solid explosives with strong confinement and give a quantification of reaction violence.The model is verified by comparing the calculated results with the experimental data.It is found that the stronger the confinement is,the faster the self-sustaining enhanced combustion is,and the more violent the reaction is for confinement failure.Moreover,the larger the charge size is,the longer the process of crack pressurization caused by gas flow and surface combustion at the initial reaction stage is,but the more violent the reaction is at the later self-sustaining enhanced combustion,and the greater the reaction degree is for confinement failure.The ignition intensity has no significant effect on the final reaction intensity of explosive charge.The results show that the theoretical burning-crack networks model is suitable for describing the effects of the intrinsic combustion rate of explosives,the confinement strength,the charge structure size,the air-gap volume and the pressure relief vent on the reaction growth of explosive charge,thus providing a theoretical method for the explosive safety design and the evaluation of explosives reaction violence.