纳米流控能量吸收耗散系统

摘要

基于纳米流控行为设计的新一代能量吸收耗散系统(nanofluidic en-ergy absorption system,NEAS)将会比传统吸能材料具有更高的能量吸收密度,而且还可以重复使用,特别是在小体积应用环境下具有显著的优势.本文从实验和计算模拟两方面综述了目前关于NEAS能量吸收耗散行为的最新研究进展,其中实验研究主要包括准静态压缩和动态压缩测试,计算模拟研究主要是采用基于经验势的分于动力学模拟方法.通过准静态压缩实验,可以测量NEAS模型的载荷–位移关系曲线,从而获得NEAS模型的临界渗透压强,了解卸载后系统是否能够恢复到加载前的状态(即是否可以重复使用),井通过载荷–位移关系曲线下面积估算NEAS模型的吸能密度;通过动态压缩实验可以测量NEAS模型对脉冲载荷的缓冲保护作用,主要体现为降低脉冲载荷幅值和扩展脉冲宽度.计算模型研究可以明确给出NEAS对外载荷的微观响应,从而可以准确了解NEAS的能量吸收耗散机制以及吸能密度的主要影响因素.本研究可以帮助我们全面了解NEAS的研究进展,为NEAS的设计与优化提供重要指导.%The energy absorption system designed on the basis of nanofluidic behavior (also called nanofluidic energy absorption system, NEAS) will have a higher energy ab-sorption density than the conventional energy absorption materials, and can be repeatedly used. Thus it shows great advantages over the conventional energy absorption materials, especially for applications with a limited volume. In this paper, we reviewed the state-of-the-art of the energy absorption behavior of NEAS from both experimental investigations and numerical studies: the experimental work mainly includes quasi-static compression and dynamic compression tests; the computational simulations are mainly based on molecular dynamics simulations developed from the empirical potentials. Using quasi-static compres-sion, we can measure the load-displacement relationship of NEAS, determine the critical infiltration pressure, understand the loading-unloading-reloading behavior of NEAS (closely related to the repeated energy absorption performance of NEAS), and estimate the energy absorption density from the area below the load-displacement curve. By use of the dynamic compression tests, the NEAS performance of the protection against the impact load can be measured, which can be represented by decreasing the impact pulse magnitude and expand-ing the pulse width. The computational studies can clearly show the micro-level response of NEAS to the external load, based on which we can fully understand the energy absorption mechanism and the main controlling parameters of energy absorption density. The present study can help researchers understand the latest research progress of NEAS, and provide an important guideline for the design and optimization of NEAS.