摘要:
为了研究云雾爆轰冲击波对生物目标的损伤效应,分别建立了云雾爆轰模型和山羊胸部有限元模型,并对模型进行了网格无关性验证和模型有效性分析,研究了冲击波作用下山羊胸部模型的响应过程,分析了不同冲击波参数对胸腔动力学响应及肺脏应力传播规律的影响,并基于数值仿真结果评估不同损伤判据对云雾爆轰肺损伤评价的适用性。结果表明:冲击波作用下,胸壁运动压缩肺脏并诱发肺内应力波传播。随着冲量和压力上升时间的增加,冲击波对胸壁的压缩作用增强,并削弱了应力波在肺脏内传播的反射特征,胸壁最大压缩速度无法完全评价肺脏损伤。以胸壁最大压缩速度作为云雾爆轰肺损伤的评价指标,可能低估肺脏的损伤程度,应同时使用胸廓压缩量与最大压缩速率作为云雾爆轰条件下的肺损伤判据。
Abstract:
To investigate the injury effects of cloud detonation shock waves on biological targets, a cloud detonation model and a finite element model of the goat thorax were established. Shock wave pressure-time histories at different locations were obtained through numerical simulation of cloud detonation and were applied as input loads to the external air-domain boundary on the blast-facing side of the goat thoracic model. The interaction process between the shock wave and the goat thorax was simulated using a fluid-structure coupling method between the air domain and thoracic tissue structures. Mesh independence verification was performed for both the cloud detonation model and the goat thoracic finite element model, and model validity was analyzed by comparison with field test results. On this basis, chest wall displacement velocity, thoracic compression process, and stress responses at different lung locations were extracted to investigate the dynamic response of the goat thoracic model under shock wave loading. By varying load parameters, including peak overpressure, impulse, and pressure rise time, the effects of different shock wave parameters on thoracic deformation characteristics and pulmonary stress propagation were analyzed. The applicability of cloud-detonation-induced lung injury evaluation indexes was further assessed by combining the maximum thoracic compression rate criterion with the pulmonary stress criterion. The results show that, under shock wave loading, chest wall motion compresses the lung and induces stress wave propagation within the pulmonary tissue. As impulse and pressure rise time increase, the sustained compression effect of the shock wave on the chest wall is enhanced, while the reflection characteristics of stress waves propagating in the lung are weakened. Therefore, the maximum thoracic compression rate alone cannot fully evaluate lung injury. Using the maximum thoracic compression rate as an evaluation index for lung injury under cloud detonation conditions has certain limitations and may underestimate lung injury severity under high-impulse and long-rise-time loading conditions. Chest compression and the maximum compression rate can be used together as auxiliary criteria for evaluating lung injury under cloud detonation conditions.