中文摘要：

文中采用有限元方法对螺旋曲杆中导波的传播特性进行了研究.运用坐标转换和二维快速傅里叶变换（2D-FFT）对导波信号进行了处理和分析,分别对不同直径和螺旋角曲杆导波的传播过程进行了数值模拟,揭示了螺旋曲杆直径、螺旋角变化对导波传播的影响规律,并分析了导波传播中的频率截止、模态分离现象.

英文摘要：

This paper deals with the propagation characteristics of guided waves in helically-curved rods by means of the finite element method. First,the coordinate transformation and the two-dimensional fast Fourier transform（ 2D-FFT） are employed to process and analyze guided waves. Then,the propagation processes of guided waves in the helically-curved rods respectively with different diameters and different helix angles are simulated,and the effects of the diameter and the helix angle on the propagation are described. Finally,the cut-off frequency and the modal separation phenomena occurring in the propagation process are discussed.