舱内复杂爆炸载荷致肺损伤的细观机理

The blast shock wave in cabin is reflected, converged and superimposed by bulkhead, forming a complex blast loading, with the characteristics of multi-peak and long positive pressure and presenting dynamic high pressure and quasi-static pressure. The complex blast loading may cause extremely serious damage to human, especially air-contained organs such as lung. At present, the energy absorption characteristics of alveolar mesoscopic structure and the mesoscopic mechanism of lung injury under complex blast loading have not been studied. Therefore, this project intends to conduct systematic and deep study on these problems by taking the goat as research object under the complex blast loading induced by explosive detonated in cabin of warship. Through experiment and numerical simulation, the propagation of complex blast loading through the thorax is studied. The response characteristics on the deformation velocity of chest wall are obtained. The correlation between lung injury, deformation evolution of alveolar mesoscopic structure and the corresponding energy absorption characteristics are analyzed to reveal the mesoscopic mechanism of lung injury under complex blast loading. Based on the dynamic model on the velocity response of chest wall and the energy dissipation mechanism of alveolar mesoscopic structure, the function relationships between complex blast loading, deformation velocity of chest wall and energy absorption characteristics of alveolar mesoscopic structure are obtained, and the theoretical model on lung injury induced by complex blast loading is established. The conclusion of this project can provide reference for the theoretical development of relevant disciplines and safety design of public places as well as the assessment and treatment for the blast injuries in cabin.

舰艇舱内爆炸冲击波受到舱壁反射、汇聚和叠加等作用，形成复杂爆炸载荷，具有多峰值、长正压时间的特点，呈现出动高压和准静态压力两种载荷形式，对人体尤其是肺脏等含气器官造成极为严重的损伤。目前，对复杂爆炸载荷作用下肺泡细观结构的吸能特性和肺部损伤的细观机理尚未开展研究。因此，本项目拟针对舱内炸药爆炸产生的复杂爆炸载荷，以山羊为研究对象，对这些问题进行系统深入的研究。通过实验和数值模拟，研究复杂爆炸载荷在胸部中的传播规律，获得胸壁变形速度响应特性，分析肺部损伤、肺泡细观结构演化及其吸能特性三者之间的关联规律，揭示复杂爆炸载荷致肺损伤的细观机理；基于胸壁速度响应动力学模型和肺泡细观结构耗能机制，获得复杂爆炸载荷、胸壁变形速度和肺泡细观结构吸能特性之间的函数关系，建立复杂爆炸载荷致肺损伤的理论模型。本项目研究结论可为相关学科理论发展、公共场所安全设计、舰艇人员伤情评估与救治防护等提供参考。

针对舱内爆炸复杂冲击波载荷作用下舰员肺损伤问题，开展了舱内爆炸载荷及动物肺损伤试验测试，舱内爆炸动物肺损伤机理，舱内爆炸冲击波致肺损伤分布，舱内爆炸肺损伤理论模型等研究。获得了舱内爆炸典型部位冲击波压力特性和经验计算模型，得到了动物肺部损伤特性和肺部损伤与爆炸冲击波载荷的关系。建立了爆炸冲击波加载方法和胸部仿真计算模型，获得了胸部载荷分布特性及胸骨变形速度随爆炸冲击波强度的变化规律。建立了肺损伤超压-比冲量准则，提出肺损伤度概念，并基于量纲分析理论，建立了肺损伤度随爆炸距离的演化规律。提出了分步模拟密闭舱室内爆炸冲击波载荷的计算方法，获得了密闭舱室内爆炸冲击波的时空分布，基于肺损伤超压-比冲量准则，预测密闭舱室内肺损伤伤情分布。将胸部简化为前后方向和左右方向由肌肉、胸壁、肺脏组成的多层复合介质，肌肉等效为弹簧阻尼单元，胸壁等效为质量单元，肺部等效为弹簧阻尼单元并看作粘弹性含气多孔结构，建立胸壁速度响应动力学模型，编程求解方程组，获得了胸骨变形位移、速度和加速度响应。研究成果为舰艇舱内爆炸舰员防护指标论证、设计及损伤评估提供支撑。