Vibration transfer characteristic of gradient-like structure based on magnetorheological fluid
Vibration transfer characteristic of gradient-like structure based on magnetorheological fluid
复制标题
基于磁流变流体的梯度结构振动传递特性
DOI：
10.7498/aps.69.20200326
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发表时间：
2020-05
影响因子：
1
通讯作者：
Liqiang Dong
中科院分区：
文献类型：
--
作者：
Dan Zhao;Shuaihu Wang;Shaogang Liu;Jin Cui;Liqiang Dong
提出了一种磁流变液构成的类梯度结构, 并通过理论建模、数值计算和实验研究了该结构的振动传递特性.在外加磁场的作用下，磁流变液表现出液-固相变特性：固-液相变的过程实际上就是振动传递阻抗的变化。因此，基于该性质，通过控制外部磁场来构建梯度状结构。从一维弹性波传播的波动方程出发，建立了梯度结构中弹性波传播的波动方程。为了在波动方程中描述磁流变流体的复剪切模量和拉梅常数与磁场强度之间的关系，基于弹性理论和粘弹性材料理论，建立了磁流变流体的等效参数模型。然后，搭建实验装置，通过实验对模型进行修正。然后，采用连续介质的离散化方法和传递矩阵法求解波动方程，得到了振级降的表达式。通过数值计算，得到了类梯度结构的振级降随入射弹性波频率和磁场强度的变化趋势。最后，对梯度结构的振动传递特性进行了实验研究，并分析了磁场强度对梯度结构振动传递特性的影响。结果表明，数值计算结果与实验结果吻合较好，从而验证了数值模型的准确性。梯度结构在均匀磁场作用下对弹性波的衰减效果优于MR流体，且具有良好的可调谐性。
In this paper, a gradient-like structure composed of magnetorheological (MR) fluids is proposed, and its vibration transfer characteristic is studied through the modeling, numerical calculation and experimental test. Under the action of an externally applied magnetic field, the MR fluid exhibits the liquid-solid transformation property: the process of transformation between solid and liquid in fact is the change of vibration-transfer impedance. Therefore, based on this property, the gradient-like structure is constructed by controlling the external magnetic field. Based on the wave equation of one-dimensional elastic wave propagation, the wave equation of elastic wave transfer in the gradient-like structure is established. In order to describe the relationship between the complex shear modulus and Lame constant of MR fluid and magnetic field intensity in the wave equation, the equivalent parameter model of MR fluid is established based on the theory of elasticity and viscoelastic materials. Then, the experimental set-up is built to modify this model through experiments. Afterward, the discretization method of continuous medium and transfer matrix method are adopted to solve the wave equation, and the expression of vibration level drop is obtained. Through the numerical calculation, the trend of vibration level drop varying with the frequency of incident elastic wave and the intensity of magnetic field for the gradient-like structure is obtained. Finally, the vibration transfer characteristic of the gradient-like structure is studied experimentally, and the influence of magnetic field intensity on the vibration transfer characteristic of the gradient-like structure is analyzed. The results show that the numerical results are in good accordance with the experimental results, thereby verifying that the numerical model is accurate. And the gradient-like structure has a better attenuation effect on the elastic wave than the MR fluid under the action of a uniform magnetic field, and has an excellent tunable property as well.