Abstract Radiation characteristics of aluminum spheres impacting aluminum thick targets have been obtained through hypervelocity impact tests aluminum spheres. Three peaks exist in the evolution of the special radiation intensity. In this paper, the influences of impact vaporization, jetting process, vaporization product's interaction with ambient gas and fragment's aerodynamic heating are quantitatively analyzed, and the reason for the occurrences of the three peaks are Figured out together with the experimental results. The radiation mechanism of the first peak is not the direct impact vaporization of the projectile, but the jetting considering the shear heating effect; the radiation mechanism of the second peak is the impact vaporization, not the interaction between the jetting vapor and the ambient gas; and the radiation mechanism of the third peak is the ablation of tiny fragments, neither the weakening of the occlusion effect of impact products that results in an increase of the radiation area, nor the shock by the jetting vapor or the shock-induced vapor. The influence of the ambient pressure on radiation characteristics is quite significant. When the ambient pressure is high, the three radiation mechanisms are coupled together in time. Therefore, it is recommended to regard the influence of the ambient pressure when conducting research on the radiation characteristics of hypervelocity impacts, otherwise the reliability of the conclusion would be affected.

中文翻译：

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超高速撞击喷射云的辐射机理分析

摘要 通过铝球超高速冲击试验，获得了铝球撞击铝厚靶的辐射特性。特殊辐射强度的演化存在三个峰值。本文定量分析了冲击汽化、喷射过程、汽化产物与环境气体相互作用、碎片气动加热等因素的影响，并结合实验结果分析了三个峰出现的原因。第一峰的辐射机理不是弹丸的直接撞击汽化，而是考虑剪切热效应的喷射；第二个峰的辐射机理是撞击汽化，而不是喷射蒸汽与环境气体的相互作用；第三峰的辐射机理是微小碎片的烧蚀，既不是冲击产物的遮挡效应减弱导致辐射面积增加，也不是喷射蒸汽或激波引起的蒸汽引起的激波。环境压力对辐射特性的影响非常显着。当环境压力较高时，三种辐射机制及时耦合在一起。因此，在研究超高速撞击的辐射特性时，建议考虑环境压力的影响，否则会影响结论的可靠性。也不会受到喷射蒸气或冲击引起的蒸气的冲击。环境压力对辐射特性的影响非常显着。当环境压力较高时，三种辐射机制及时耦合在一起。因此，在研究超高速撞击的辐射特性时，建议考虑环境压力的影响，否则会影响结论的可靠性。也不会受到喷射蒸气或冲击引起的蒸气的冲击。环境压力对辐射特性的影响非常显着。当环境压力较高时，三种辐射机制及时耦合在一起。因此，在研究超高速撞击的辐射特性时，建议考虑环境压力的影响，否则会影响结论的可靠性。