Miao Siqi, Zhong Yifeng, Zhang Mingtao, Liu Rong
School of Civil Engineering, Chongqing University, Chongqing 400045, China.
Key Laboratory of New Technology for Construction of Cities in Mountain Area, Chongqing University, Chongqing 400045, China.
Materials (Basel). 2024 Aug 16;17(16):4067. doi: 10.3390/ma17164067.
The incorporation of viscoelastic layers in laminates can markedly enhance the damped dynamic characteristics. This study focuses on integrating viscoelastic layers into the composite facesheet of the bowtie-shaped honeycomb core composite sandwich panel (BHC-CSP). The homogenization of the damped BHC-CSP is performed by employing the variational asymptotic method. Based on the generalized total energy equation, the energy functional of the representative unit cell of the damped BHC-CSP is asymptotically analyzed. The warping function, derived following the principle of minimum potential energy, provides a basis for obtaining the corresponding Euler-Lagrange equation to ascertain the equivalent elastic properties of the damped BHC-CSP. Utilizing the developed two-dimensional equivalent model, the free-vibration characteristics of the damped BHC-CSP are examined across diverse boundary conditions while delving into the impact of an external viscous damping layer on the natural frequency of the damped BHC-CSP. The results reveal that intensified boundary constraints effectively diminish the effective vibration region of the damped BHC-CSP, thereby enhancing its overall stability. The introduction of a PMI foam layer proves effective in adjusting the stiffness and mass distribution of the damped BHC-CSP. Resonance characteristics are explored through frequency and time-domain analyses, highlighting the pivotal roles of the excitation position and receiver point in influencing the displacement and velocity responses. Although the stiffness is improved by incorporating a PMI foam layer, its effect on the damping performance of the damped BHC-CSP is minimal when compared to the T-SW308 foam layer.
在层压板中加入粘弹性层可以显著提高其阻尼动态特性。本研究重点在于将粘弹性层集成到领结形蜂窝芯复合夹芯板（BHC-CSP）的复合面板中。采用变分渐近方法对阻尼BHC-CSP进行均匀化处理。基于广义总能量方程，对阻尼BHC-CSP代表性单胞的能量泛函进行渐近分析。根据最小势能原理推导得到的翘曲函数，为获得相应的欧拉-拉格朗日方程以确定阻尼BHC-CSP的等效弹性性能提供了基础。利用所建立的二维等效模型，研究了阻尼BHC-CSP在不同边界条件下的自由振动特性，同时探讨了外部粘性阻尼层对阻尼BHC-CSP固有频率的影响。结果表明，强化的边界约束有效地减小了阻尼BHC-CSP的有效振动区域，从而提高了其整体稳定性。引入PMI泡沫层被证明能有效调整阻尼BHC-CSP的刚度和质量分布。通过频域和时域分析探索共振特性，突出了激励位置和接收点在影响位移和速度响应方面的关键作用。虽然加入PMI泡沫层提高了刚度，但与T-SW308泡沫层相比，其对阻尼BHC-CSP阻尼性能的影响最小。
