三明治夹芯基座阻抗阻尼隔振特性分析

利用复合材料良好的阻尼特性和结构可设计性,将目前的刚性基座替换为三明治夹芯基座,分析了基座阻抗和阻尼对隔振效果的影响;设计了直骨架和曲骨架2种夹芯基座结构形式,对支撑骨架厚度和曲率半径等结构参数对基座力学性能的影响进行了分析,并采用DMTA方法对高阻尼的聚氨酯芯材的损耗因子进行了测量;通过试验和有限元方法对2种结构形式的三明治夹芯基座静刚度特性进行了比较;采用激振器和偏心电机2种激振方式对夹芯基座进行了隔振特性试验研究,以功率流为隔振效果评估指标,分析了不同激振方案下2种夹芯基座的隔振效果.结果表明:通过对三明治夹芯基座的阻抗阻尼设计,能够有效地衰减高频驻波,具有较好的隔振效果.

Isolation of vibration by the impedance and damping of a composite sandwich base

A design method that uses the damping properties of composite materials in a sandwich base was developed as an alternative to rigid bases. The effect of impedance and damping on vibration isolation was then analyzed. Two sandwich base structures were built; one used a vertically braced base, the other an crooked braced base. The thickness and curvature radius of the braced bases were then optimized. The core, of high damping polyurethane material, was then incorporated in the base, and its loss factor was measured by dynamic mechanical thermal analysis (DMTA). Two sandwich bases were produced, and their static stiffness was calculated by experiments and the finite element method (FEM). The effect of vibration isolation was tested by different vibrator systems, and measurements of power flow were used to evaluate the effectiveness of their isolation. The results, in terms of impedance and damping, indicate that the sandwich base restrains high frequency standing waves, providing a better isolation effect.