基于共振法的黏弹性细棒力学参数宽频测试  

Determination of dynamic parameters of viscoelastic thin bar using resonance measurement method under pulse excitation

作　　者：侯宏[1] 余虎[1] 孙亮[1] 

机构地区：[1]西北工业大学航海学院,西安710072

出　　处：《振动与冲击》2015年第9期107-110,共4页Journal of Vibration and Shock

基　　金：国家自然科学基金资助(11204242;11474230)

摘　　要：在黏弹性细棒力学参数共振法测量的基础上提出了一种宽频测试方法。激振器产生了波形可控的宽频短脉冲信号,对黏弹性细棒进行纵向激励。利用激光测振仪分别测量激振器和细棒自由端的振动速度响应,通过自由端与激振端响应信号在宽频范围的幅值比和相位差,根据共振法原理可解算共振频率处的储能模量和损耗因子。另外,对测试过程进行了有限元仿真。结果表明:利用该测试方法,通过较少次数测试可得到与黏弹仪数据吻合的动力学参数,而有限元分析可对测试提供指导。A broadband method to identify the dynamic parameters of viscoelastic bar using resonance measurement under pulse excitation was presented. Controllable broadband pulses were generated by an exciter and used to produce the longitudinal vibration of a viscoelastic thin bar. The vibration velocities at the free end of the bar and the exciter were measured respectively by a laser vibrometer. The velocity ratio can be obtained over a wide frequency range and thus,the storage modulus and the loss factor can be determined at resonant frequencies. Moreover,the testing process was simulated by finite element calculation. The proposed method is demonstrated valid and accurate by comparing the parameters obtained with the results of the viscoelastic apparatus test.

关 键 词：黏弹性细棒 有限元分析 宽频脉冲 力学参数 

分 类 号：TB523[理学—物理]