中文摘要：

利用COMSOL仿真和实验，研究并证实了充液管道纵向导波测量液体黏度的可行性．有限元仿真采用声固耦合模块、特征值求解器来获得导波实波数、复频率和波结构，以及不同模态的位移和声压分布．实波数和频率实部构成群速度频散曲线，频率虚部和频率实部构成衰减频散曲线．计算和测试了不同充液属性时纵向导波的群速度和衰减频散曲线．黏度不影响导波群速度频散曲线，黏度增加时，衰减系数增大；密度增加时，导波群速度和频散区的衰减均变小，而非频散区的衰减不变；纵波速度增加时，群速度和衰减频散曲线均右移．

英文摘要：

The feasibility of utilizing longitudinal(L)guided waves in liquid-filled pipes to measure viscosity is demonstratedby deploying COMSOL software and experiments.The real wavenumbers,complex frequencies and wavestructures of guided waves and the displacement and acoustic pressure distributions of various modes are calculated byconfiguring the finite element simulations as acoustic-solid interaction module and eigenvalue solver.The realwavenumbers and the real parts of the complex frequencies constitute the group velocity dispersioncurves(GVDCs),and the imaginary and real parts of the complex frequencies constitute the attenuation dispersioncurves(ADCs).GVDCs and ADCs with different liquid properties are calculated and tested.The liquid viscosity hasno effect on the GVDCs while the ADCs go higher as the viscosity increases.Both the ADCs in the dispersion regionand GVDCs go lower while the ADCs in the plateau region remain constant as the liquid density increases.Both theGVDCs and ADCs stretch and shift rightwards as the compressional wave velocity increases.