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研究了导波在正交各向异性黏弹性复合板中传播的色散特性、波结构及功率流密度。基于二维平面运动方程,采用谱有限元方法得到了导波色散的特征方程。分析了正交各向异性黏弹性板中各向异性和黏性对能量速度和波结构的影响,以及基底对导波功率流密度的影响。数值研究结果表明:导波沿纤维方向传播的能量速度大,材料的黏性对速度影响较小,但会减小波结构的幅度;在高频时,基底的存在使两个基本模态的功率流密度分别集中到波导的上下表面,形成弱色散、高衰减及无色散、零衰减的表面波。数值模拟结果为导波用于复合材料定量无损检测和性能评价提供理论依据。
The dispersion characteristics, wave structure and power flow density of the guided wave propagating in the orthotropic viscoelastic composite plate are studied. Based on the two-dimensional plane motion equation, the characteristic equation of guided wave dispersion is obtained by using the spectral finite element method. The influence of anisotropy and viscosity on the energy velocity and wave structure in orthotropic viscoelastic plates and the influence of the substrate on the power density of the guided wave were analyzed. The numerical results show that the energy of the guided wave propagating along the fiber direction is large, and the viscosity of the material has a small effect on the velocity, but it will reduce the amplitude of the wave structure. At high frequency, the presence of the substrate makes the two fundamental modal Power flow density were concentrated to the upper and lower waveguide surface, forming a weak dispersion, high attenuation and no dispersion, zero attenuation of surface waves. The numerical simulation results provide a theoretical basis for the guided waves to be used in quantitative nondestructive testing and performance evaluation of composite materials.