摘要
本文探讨了多孔ＴＮＴ炸药中热点形成的粘塑性塌缩机理。在研究孔隙周围介质的粘塑性运动和由此引起的加热时，考虑了熔化效应，并对所建立的模型进行了数值计算。结果表明，在约３ＧＰａ的较低幅值冲击波加载下，受熔化影响，在具有不同尺寸的孔隙边界附近，熔化区温度均保持在熔点附近，而熔化区的存在保证了加热层具有一定的深度。对大颗粒样品，由于孔隙塌缩过程中熔化区的不断扩大，在熔化区中屈服强度为零，粘性很小，孔隙边界最终可以达到较高的塌缩速度。因此，在孔隙闭合阶段必须考虑点火的流体动力学机理；而对细颗粒样品，熔化则强烈地降低了点火感度。
The viscoplastic collapse mechanism of hot·spot formation in pressedporous TNT charges was studied.Amodel was proposed and numerically calculatedbased on the viscoplastic motion and induced heat of the media around cavities due to themeIting effect.The resuIts showed that in moIten region near the boundary of cavitieswith different dimensions the temperature was kept near the meIting point, and the exis-tence of the molten region ensured a heat layer with a certain depth under the shockpressure with amplitude of about 3 GPa. Due to the enlargement of molten region dur-ing the collapse of cavities,the yield stress tended to zero and viscoplativity was verysmall in the moIten region,these factors may result in a high velocity of cavity boundarycollapse, therefore on the close stage of cavity the fluid-dynamics mechanism of ignitionmust be considered for these samples from large granular,while the melt remarkablydecreased the sensitivity of ignition for these samples from fine granular.
出处
《含能材料》
EI
CAS
CSCD
1994年第2期36-48,共13页
Chinese Journal of Energetic Materials
基金
中国工程物理研究院流体物理研究所冲击波物理与爆轰物理实验室资助项目
