A basic problem is energy absorption degradation of conventional automotive crash-boxes due to Euler instability.Here,a novel crash-box based on the combined action of elastic cement' s multi-stage radial flow and crushable cylindrical-corrugated components was proposed.Oswald-deWaele fluid constitutive model was employed to characterize the rheological properties of elastic cement,the model parameters were determined through tests.Through dropping-hammer impact tests,impact force transfer characteristics of crushable cylindrical-corrugated components were studied.The continuity equation and governing differential equation of elastic cement in multi-stage radial flow were established.With Oswald-deWaele model,the expressions for elastic cement' s radial velocity distribution at different radial positions and pressure gradient were deduced.The influence of inertia effect on pressure gradient was analyzed based on the average inertia method.Further,the calculation method of buffer force during elastic cement unsteadily flowing in the crash-box was obtained.In order to verify the rationality of the theoretical calculation,the crash-box prototype was designed,fabricated and assembled,and a dropping-hammer test system was constructed for impact tests under two different heights.The impact forces obtained with tests and those calculated with the theoretical method were compared,and the caused errors were analyzed.%针对汽车碰撞盒容易出现欧拉失稳导致吸能特性劣化问题,研究了一种柱状波纹压溃与胶泥流动产生压差缓冲的碰撞盒.通过实验研究了所用胶泥材料的Oswald-deWaele冥律流体本构模型,得出了胶泥的模型参数;采用落锤冲击实验方法研究了柱状波纹压溃件的冲击力传递特性;建立了胶泥在多级径向通道中流动的连续性方程和控制微分方程,推导了不同径向位置的径向速度分布表达式和压力梯度;采用平均惯性法分析了惯性效应对于压力梯度的影响,得到了胶泥在碰撞盒中非稳态流动缓冲力计算方法.为验证理论计算的合理性,设计制作了胶泥多级径向流动节流与柱状波纹压溃共同作用的碰撞盒样机,利用落锤冲击试验机和力传感器构建了冲击测试平台,并对缓冲装置进行了两种不同高度的冲击实验,比较了不同冲击能量下的胶泥缓冲器传递冲击力的测试值与理论值,分析了产生误差的原因.
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