基于区间B样条小波有限元的转子裂纹定量识别

研究一种基于区间B样条小波有限元的转子横向裂纹定量识别方法.构造包含转动惯量影响的区间B样条小波Rayleigh梁单元,高精度求解裂纹转子前三阶固有频率,获得裂纹相对位置和相对深度作为变量的固有频率解曲面.然后将实测的裂纹转子前三阶固有频率作为裂纹识别问题的输入,利用三条等高线的交点定量识别出裂纹存在的相对位置和相对深度.数值仿真和试验研究结果表明,该方法鲁棒性强,单元数量少,辨识精度和效率高,为转子系统裂纹定量识别提供了新方法.

QUANTITATIVE IDENTIFICATION OF ROTOR CRACKS BASED ON FINITE ELEMENT OF B-SPLINE WAVELET ON THE INTERVAL

Based on finite element of B-spline wavelet on the interval (BSWI),the quantitative identification method of transverse crack for rotor systems is studied.The BSWI Ray- leigh beam element considering rotatory inertia effect is con- structed to solve the first three natural frequencies of the cracked rotor with high precision,and the first three frequen- cies solution curve surfaces of normalized crack location and size are obtained by using surface-fitting technique.Then the first three metrical natural frequencies are employed as inputs of the solution curve surfaces.The intersection of the three frequencies contour lines can predict the normalized crack lo- cation and size.The numerical and experimental examples are given to verify the validity of the beam element for crack quan- titative identification in rotor systems.The new method can be applied to prognosis and quantitative diagnosis of crack in rotor systems.