Abstract
Magnetic sensors are widely used in aeroengines and their health management systems, but they are rarely installed in the engine hot section due to the loss of magnetic properties by permanent magnets with increasing temperature. The paper presents and verifies models and design solutions aimed at improving the performance of an inductive sensor for measuring the motion of blades operated at elevated temperatures (200–1000 °C) in high pressure compressors and turbines. The interaction of blades with the sensor was studied. A prototype of the sensor was made, and its tests were carried out on the RK-4 rotor rig for the speed of 7000 rpm, in which the temperature of the sensor head was gradually increased to 1100 °C. The sensor signal level was compared to that of an identical sensor operating at room temperature. The heated sensor works continuously producing the output signal whose level does not change significantly. Moreover, a set of six probes passed an initial engine test in an SO-3 turbojet. It was confirmed that the proposed design of the inductive sensor is suitable for blade health monitoring (BHM) of the last stages of compressors and gas turbines operating below 1000 °C, even without a dedicated cooling system. In real-engine applications, sensor performance will depend on how the sensor is installed and the available heat dissipation capability. The presented technology extends the operating temperature of permanent magnets and is not specific for blade vibration but can be adapted to other magnetic measurements in the hot section of the aircraft engine.
Highlights
The need to monitor the health of the blades of jet engines and stationary turbines results from the well-known problems with blade damage [1] caused by ingested foreign objects or material fatigue
Blade Health Monitoring (BHM) systems have good commercial prospects, especially in power generation turbines, which are increasingly operated in the off-design mode due to fluctuating market demand for energy
The sensor consists of a probe and a specialized conditioning system [33], which can work near the turbine at a temperature as high as 150 °C if it is made from high temperature electronic components [34]
Summary
The need to monitor the health of the blades of jet engines and stationary turbines results from the well-known problems with blade damage [1] caused by ingested foreign objects or material fatigue. Blade Health Monitoring (BHM) systems have good commercial prospects, especially in power generation turbines, which are increasingly operated in the off-design mode due to fluctuating market demand for energy. F-35 fighter [3], with magnetic sensors installed in the engine compressing section. The digital transformation of aviation requires new robust sensors for engine development, ground maintenance, and in-flight health management and prediction. Magnetic sensors are better suited for monitoring systems than optical [4] or capacitive sensors [5,6]. Only sensors with high durability and reliability are acceptable
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
