Study on measuring method of radial geometrical deformation of the fixture fringe of casing

Abstract

In the aero engine, as one of the most important supporting components, casing has to suffer various loads such as gravity, axial force of gas, inertial force and inertial moment etc transmitted from the turbine rotor and other structural parts, which may lead to the radial geometrical deformation of the casing, especially at the region of the fixture fringe. Also, oversized deformation of the fixture fringe might produce huge hidden dangers to the flight. Therefore, aiming at the measuring assignment of the radial geometrical deformation of the fixture fringe, a non-contact measuring system is set up in the paper, as well as the mathematical model presented in detail. Composed of auxiliary fixing devices, force loading devices and laser displacement sensors etc, the measuring system could be utilized to detect the deformation at every mount on the outer wall of the inspected casing, and then calculate the deformation parameters of the fixture fringe by the mathematical model. As the experiment results shown, through collecting the outputs of the sensors and substituting them into the mathematical model established, the contour features and eccentricity displacement of the fixture fringe after deformation could be derived, which is of certain practicality in the improvement of the whole performance of the aero engine.