预防颅脑冲击损伤的仿生缓冲结构设计

水面舰船遭受水下爆炸冲击时，舰员和设备的安全防护至关重要。本项目针对水下爆炸冲击谱的宽频特点，利用动物模型、物理模型开展不同位移谱、速度谱和加速度谱下颅脑组织损伤机理和病理的生物力学研究，确定脑震荡、脑功能缺失、脑损害等发生条件，建立考虑颅骨层、脑脊液层、脑实质层的颅脑有限元模型，将力学参数与医学指标相结合，分析致伤物理参数与病理损伤之间的关联关系，揭示外力引起颅脑损伤的病理生理改变的内在机制。在此基础上，引入自然界动物生理结构特征和多种缓冲吸能机制，提出剪切增稠液填充手性负泊松比结构和多孔泡沫填充点阵结构的设计新思想，结合医学评价指标开展宽频域抗冲击防护结构的仿生学设计，揭示其在小位移高频冲击和大位移中低频冲击条件下的粘弹塑性响应规律及阻尼能耗机制，通过多种生物力学缓冲机制的融合，优化载荷传递路径和能耗效率，实现抗冲击仿生防护结构的多功能一体化设计，为提升我国舰艇船员生存能力提供保障。

When the surface ship is subjected to the impacts of underwater explosions, the safety protection of the crew and equipment is very important. In view of the broadband characteristics of the impact spectrum of underwater explosions, this project makes use of animal model and physical model to carry out the biomechanical studies on brain tissue injury mechanism and pathology under different displacement, velocity and acceleration spectra, and determines the conditions of concussion, brain function loss and brain damage. A finite element model of brain is established taking into account the skull layer, cerebrospinal fluid layer and brain parenchyma layer. By combining mechanical parameters with medical indicators, the correlation between physical parameters of injury and pathological damage is analyzed, and the internal mechanism of pathophysiological changes caused by external forces is revealed. On this basis, the physiological structure characteristics of animals in nature and a variety of buffer energy absorption mechanisms are introduced, and a new design idea of chiral negative poisson's ratio structure filled with shear thickening liquid and lattice structure filled with porous foam is proposed. Combined with the medical evaluation indicators, the bionic design of the broad-frequency anti-impact protection structure is carried out, and the viscoelastic-plastic response law and damping energy dissipation mechanism under the conditions of small displacement in high frequency impact and large displacement in medium-low frequency impact are revealed. Through the fusion of various biomechanical buffer mechanisms, the load transfer path and energy dissipation efficiency are optimized, and the multi-functional integrated design of the anti-impact bionic protection structure is realized. The study of this project will provide a guarantee for improving the survivability of the crew of China's ships.