基于瞬时空腔成形自相似的钝击效应评估模型研究

Temporary cavity that is the main main physical phenomenon during blunt impact, is used to assess the blunt effect. Meanwhile, blunt energy is an important factor of affecting cavity forming. Considering the cooperation and relevance between cavity forming and energy transfer， as well as the advantages of visualization of cavity forming, research on the assessment model for blunt effect based on the self-similarity of cavity forming will be proposed. This project intends to study the influence mechanism of geometric parameter, structural parameter, motion parameter and material parameter on temporary cavity forming, analyze the forming law, and propose the characteristic parameters of cavity forming. The self-similar characteristics of cavity forming under multi-parameter characterizations will be analyzed and verified, and the theoretical model of cavity forming will be established. The time-space effect between energy transfer and temporary cavity in blunt will be explored, and the law between energy transfer and cavity forming will be revealed to be used to establish the quantitative corresponding relationship between them. On this basis, the main factors of blunt assessment will be resolved, and a assessment model for blunt effect based on combing cavity assessment and energy criteria. The model overcomes the limitations of single assessment model. It not only provides a reference for blunt assessment, but also provides insight for the establishment of other assessment models.

瞬时空腔是防护后钝击的主要物理现象，也是钝击效应评估的重要指标，而钝击能量是空腔成形的重要影响因素。鉴于空腔成形与能量传递的协同性和关联性，结合空腔成形可视化的优势，提出基于瞬时空腔成形自相似的钝击效应评估模型构建研究。拟通过研究几何参数、结构参数、运动参数、材料参数等对瞬时空腔成形的影响机制，分析瞬时空腔成形规律，提出表征空腔成形的特征参数；分析并证实多参数表征下空腔成形的自相似特性，建立瞬时空腔成形理论模型；探索钝击过程中能量传递与瞬时空腔之间的时空效应，揭示能量传递与瞬时空腔成形之间的作用规律，建立两者之间的定量对应关系。在此基础上，解析钝性损伤评估的主要因素，构建瞬时空腔与能量融合的钝击效应评估模型。该模型的建立克服单一模型评估的局限性，不仅为钝性损伤评估提供参考，也为其他评估模型的建立提供了可以借鉴的新思路。

防护后钝击是极其复杂的瞬时冲击行为，主要表现为空腔效应、压力波效应及远达效应等。瞬时空腔是防护后钝击中最易观察和获取的物理现象之一。本项目针对防护后钝性损伤评估问题，提出基于瞬时空腔成形的钝击效应评估研究。通过软防护后明胶靶标钝击实验获取瞬时空腔，利用图像处理提出了空腔轮廓提取方法。基于实验数据，分析了瞬时空腔成形特点，实验数据表明瞬时空腔在二维形态上可以描述为半椭圆形，提出了瞬时空腔表征参数。研究了钝击速度、不同杀伤元结构对空腔成形的影响，证实了多参数表征下空腔成形的自相似特性。探究了钝击能量与瞬时空腔之间的时空效应，初步揭示能量传递与瞬时空腔成形之间的作用规律，并进行了不同杀伤元钝性损伤的评估。该研究可以为防护后钝击的评估研究提供借鉴，也可为杀伤元和防护材料的优化提供参考。