针对鼓风机叶片在共振中因大变形而引起的裂纹或断裂问题,基于双目立体视觉原理和数字图像相关法,并结合振动学理论,研究了小尺寸风机叶片在振动过程中的变形及动态应变。结果表明:叶片的最大应变位于叶根处,且整体应变随着正弦振动的激励呈现交变状态;与应变片法测得的应变和激光测振仪测得的位移相比,采用VIC-3D数字图像相关法测得叶片根部的应变和位移相对误差分别约为4.0%和3.5%,该测量方法易于操作,测量精度高。

Aiming at the crack or fracture problem of blower blade caused by large deformation in resonance, based on the principle of binocular stereovision and digital image correlation method, combined with the theory of vibration, the deformation and dynamic strain of small fan blade during vibration were studied. The results show that the maximum strain of the blade was located at the blade root, and the overall strain of the blade alternated with the excitation of sinusoidal vibration. Compared with the strain measured by the strain gauge method and the displacement measured by the laser vibrometer, the relative errors of the strain and displacement measured by the VIC-3D digital image correlation method at the blade root were about 4. 0% and 3. 5%, respectively, this measurement method was easy to operate and has high measurement accuracy.