Detection of Cracks in Rotating Shafts - An Analytical and Experimental Investigation

本项目研究了裂纹转轴的瞬态响应。它包括分析和实验两个部分。在解析部分，裂纹将用集中的力和力矩来表示，并根据裂纹位置的条件，假设裂纹在运动过程中是开合的。轴将通过一个或多个临界速度加速或减速，响应将使用伽辽金方法确定。研究了加减速速率、裂纹深度、裂纹位置和偏心距等因素的影响。将寻求最大响应的近似公式。在本项目的实验部分，激光扫描数据将从未破裂和破裂的轴模型中获得，并与解析等效模型进行关联。作为这项研究的结果，预计将有一个更好的理解裂纹结构的行为，改进的诊断程序，以检测各种类型的旋转机械的小裂纹将出现。* * * / /

This project examines the transient responses of cracked rotating shafts. It comprises an analytical and experimental component. In the analytical part, the crack will be represented by concentrated forces and moments, and will be assumed to open and close during the motion depending on the conditions at the crack location. The shaft will be accelerated or decelerated through one or more critical speeds, and the response will be determined with the use of Galerkin's method. The effects of acceleration and deceleration rate, crack depth, crack position and eccentricity will be investigated. Approximate formulas for the maximum response will be sought. In the experimental part of this project, laser scan data will be obtained from both uncracked and cracked shaft models and correlated with the analytically equivalent models. As a result of this study, it is expected that there will be an improved understanding of the behavior of cracked structures, and that improved diagnostic procedures for detecting small cracks in various types of rotating machinery will emerge.*** //