基于纳米流体增强微桁架结构的爆炸冲击防护系统研究

The program seeks to develop, model and demonstrate a fluidic truss blast protection system that will enable the defeat of current and future blast threats. Based on the structure framework of metallic hollow micro-truss, which has exhibited superior architecture for lightweight protection from impulsive loads, exceeding the energy absorption per mass of foams by a factor of 4, a new emerging nanofluid material with high performance of energy absorption will be filled into the hollow micro-truss. Preliminary studies have demonstrated that this new material has the advantages of fast response speed and extraordinary high energy absorbing efficiency. Further researches concerning the system's energy absorption mechanisms and optimization (such as truss structure design and optimization, the nano-fluid's molecular scale behavior under confined space, nano-fluid/metallic micro-truss package, material recycling system) are still needed. This project will establish a multi-scale and multi-field coupling simulation platform. And the performance of this fluid truss material will be studied from the nano-scale melucular level to the macroscopic level. At the same time, parallel experiments will be conducted to study the mechanical behavior of the structure under blast/impact threats. Furthermore, we also seek to develop the intelligent blast protection structure through the regulation of micro-nano-fluid properties and macro-structure design.

本项目计划开发、模拟和论证一种新材料，用于抵御潜在的爆炸冲击威胁。该新材料将空心微桁架低密度结构作为基础框架，其吸能密度是普通泡沫材料的4倍以上，具有优异的结构性能；同时，一种具有超高性能吸能效果的纳米流体材料将被填充入空心微桁架结构中。该新方法将以上两个创新的理念（微桁架结构和纳米吸能流体）有机结合，通过多级构架与组装，将大大提高爆炸冲击安全防护性能，远远高于现有的技术水平。初步研究显示该材料具备优越的响应速度和吸能效率等特点，而关于该材料的吸能机理与优化设计（如微桁架结构的设计和优化，分子尺度纳米流体性质、系统结构封装、材料循环使用等）仍需进一步的系统研究。本项目将建立多尺度、多场耦合模拟设计平台，从分子尺度到宏观性能系统地研究纳米流体增强微桁架结构的抗冲击性能；同时展开相应的实验，研究该结构在冲击荷载下的力学行为，并通过调控微观纳米流体和宏观系统结构设计实现智能抗冲击结构。

本项目开发设计了一种新的安全防护结构：轻质量高性能抗爆炸冲击防护结构——纳米流体增强微桁架结构。该新安全防护结构以空心微桁架低密度结构作为基础框架，其吸能密度是普通泡沫材料的4倍以上，具有优异的结构性能；同时，将一种具有高吸能密度的纳米流体填充进中空微桁架结构中，以达到1+1>2的效果，进一步提高结构的吸能密度。该方法创造性的将微桁架结构和纳米流体进行有机结合，通过合理组装和结构设计，进一步提高结构的安全防护性能，其吸能效果远远高于现有材料。.本项目通过多尺度、多场耦合模拟，通过分子动力学模拟从分子尺度出发研究纳米流体在纳观状态下的吸能特性，并结合有限元计算建立纳米流体增强微桁架结构的模型研究其在准静态和冲击载荷下的响应。同时展开相应的实验工作，研究纳米流体微桁架结构的力学特性，并对其几何参数等进行设计优化。最后将纳米流体微桁架结构应用到防弹衣领域，检验其实际应用效果，为纳米流体的有效应用提供指导。