This paper describes a rapid and efficient nonlinear non-resonance mechanism for low-to-high-frequency energy scattering, which is referred to as intermodal targeted energy transfer (IMTET). To present the IMTET mechanism in the most basic setting, a blast-excited two-DOF linear system with a single clearance is considered. The impact interactions facilitate rapid transfer of oscillation energy from an initially excited, low-frequency symmetric mode to a high-frequency antisymmetric mode with substantially higher modal dissipative capacity. Numerical exploration reveals almost immediate drastic reduction of the system response amplitude caused by nonlinear “modal energy redistribution” within its modal space. Characteristic damping time of the system exhibits a multi-fold reduction. This process requires a rather limited number of impacts; only one or two impacts are enough to cause an immediate significant suppression of the system response. The results are robust over a broad range of blast amplitudes. Matrix formalism based on eigenvalue decomposition of the state matrix is developed to obtain an implicit analytic description of the process. Then, estimations for the main characteristics of the IMTET process, such as activation threshold and expected efficiency, are obtained. The results show a rather weak dependence of the characteristic damping time of the system on the coupling strength between oscillators, and relatively strong dependence on the ratio of the clearance to the blast intensity. The findings reported in this study have potential applications for passive, rapid and efficient shock mitigation and energy absorption in engineering structures under extreme loads by redistributing the input shock energy to high-frequency structural modes.

本文介绍了一种用于低频到高频能量散射的快速有效的非线性非共振机制，该机制称为联运目标能量转移（IMTET）。为了在最基本的情况下呈现IMTET机制，考虑了具有单间隙的爆炸激发两自由度线性系统。冲击相互作用促进了振荡能量从最初被激发的低频对称模式向具有明显更高的模态耗散能力的高频反对称模式的快速转移。数值研究表明，由于模态空间内的非线性“模态能量重新分布”，导致系统响应幅度几乎立即急剧降低。该系统的特征阻尼时间表现出多重降低。这个过程需要相当有限的影响。仅一两个影响就足以立即严重抑制系统响应。结果在宽广的爆炸振幅范围内都是可靠的。开发了基于状态矩阵特征值分解的矩阵形式主义，以获得过程的隐式解析描述。然后，获得对IMTET过程主要特征的估计，例如激活阈值和预期效率。结果表明，系统的特征阻尼时间对振子之间耦合强度的依赖性很小，而对间隙与爆炸强度之比的依赖性较强。这项研究报告的发现可能对被动，