Identification Method of Blade Vibration with High EO Based on Virtual Sensor Interpolation

Abstract

The vibration of blades and the corresponding high-cycle fatigue fracture are the main problems in the development and operation of high-performance turbomachinery. High engine order (EO) vibration caused by the periodic pulsation of the flow parameters of high-load blades under the disturbance of wakes which is the main factors for high-cycle fatigue. Therefore, the high EO vibration monitoring is important for the diagnosis and early warning of high-cycle fatigue. A method is proposed for reconstruction and identification of high EO signals in rotating blades based on virtual sensor interpolation method, which can be a good solution for the vibration of blades with high EO, and can achieve vibrations up to 60EO when the angle of sensor installation is 6 degrees. Theoretically, only two sensors are needed for this method and four sensors can be used to ensure the identification accuracy in practical applications. What's more, only one start up or stop of the turbomachinery is needed to identify the vibration of blade, which simplifies the test steps. The method can be used for the vibration monitoring and identification of high-end rotating machinery such as aircraft engine, which has a large number of stationary blades and vibrates in high order mode and high-EO. The comparison between the experimental data and the simulation results indicates the effectiveness and accuracy of this method.