Shang Wei, Li Hulin, Liu Jinghong, Liu Jinzhao
Appl Opt. 2022 Dec 10;61(35):10433-10438. doi: 10.1364/AO.471678.
The photoelastic method is an experimental technique that combines optics and mechanics for a stress analysis. The photoelastic phase-shifting technique is different from the moiré, holography, and speckle phase-shifting techniques, which only need to measure one parameter. The photoelastic phase-shifting technique needs to assess isoclinic and isochromatic parameters, which affect each other, seriously hindering the development of the phase-shifting photoelasticity method. First, the interaction between the isoclinic and isochromatic parameters is analyzed in detail. Secondly, an algorithm is proposed to adjust the mutation and obtain the correct isoclinic parameter affected by the isochromatic parameter. This method can effectively eliminate the influence of the isochromatic parameter. The isoclinic parameter is consistent with the theoretical value, which verifies the effectiveness of this method. Finally, the photoelastic method uses the proposed algorithm to test the stress at different positions of the turbine blade root. Moreover, the bearing capacity of the turbine blade root is analyzed to provide support for the safe use and optimization design of the turbine.
光弹性方法是一种将光学和力学相结合用于应力分析的实验技术。光弹性相移技术不同于仅需测量一个参数的莫尔、全息和散斑相移技术。光弹性相移技术需要评估等倾线和等色线参数，而这两个参数相互影响，严重阻碍了相移光弹性方法的发展。首先，详细分析了等倾线和等色线参数之间的相互作用。其次，提出了一种算法来调整突变并获得受等色线参数影响的正确等倾线参数。该方法可以有效消除等色线参数的影响。等倾线参数与理论值一致，验证了该方法的有效性。最后，光弹性方法使用所提出的算法测试涡轮叶片根部不同位置的应力。此外，分析了涡轮叶片根部的承载能力，为涡轮的安全使用和优化设计提供支持。
