CN-116448430-B - Online monitoring device and method for crack of test rotor of vertical rotary tester

Abstract

The invention discloses an on-line monitoring device and method for a crack of a test rotor of a vertical rotary tester. The device comprises a vibration sensor, a key phase sensor, an on-line monitoring system signal processing module and a crack monitoring analysis module, wherein the vibration sensor arranged on a main shaft system is used for acquiring a vibration original signal of the main shaft system, the key phase sensor arranged on the main shaft system is used for acquiring a pulse signal generated by one rotation of a rotor, the on-line monitoring system signal processing module is used for processing signals transmitted by the vibration sensor and the key phase sensor to acquire rotor vibration amplitude and rotor rotating speed, the signals are transmitted to crack monitoring analysis software, and then the crack initiation and expansion of the rotor are determined by monitoring and analyzing the change rule of the rotating speed value of the rotor when the maximum amplitude and the maximum amplitude are generated along with the cycle number. According to the method, abnormal alarm prompt of the crack on-line monitoring system is used for preventing rotor cracks caused by crack initiation and crack propagation of the test rotor, so that early shutdown inspection is realized.

Inventors

• LI XIAOYU
• Zhu Piyu
• QU MINGMIN

Assignees

• 浙江海骆航空科技有限公司

Dates

Publication Date

20260512

Application Date

20230323

Claims (4)

1. 1. The on-line monitoring device for the crack of the test rotor of the vertical rotary tester is characterized by comprising a vibration sensor (2), a key phase sensor (6), an on-line monitoring system signal processing module (3) and an on-line crack monitoring analysis module (4), wherein the vibration sensor (2) is arranged on a main shaft system of the vertical rotary tester and is used for acquiring a vibration original signal of the main shaft system, the key phase sensor (6) is arranged on the main shaft system of the vertical rotary tester and is used for acquiring one or more pulse signals generated by one circle of rotation of the test rotor, the on-line monitoring system signal processing module (3) is used for processing signals transmitted by the vibration sensor and the key phase sensor, acquiring the vibration amplitude of the rotor and the rotation speed of the rotor and transmitting the vibration amplitude and the rotation speed of the rotor to the on-line crack monitoring analysis module (4), and the on-line crack monitoring analysis module (4) is used for monitoring and analyzing the rule that the maximum amplitude of the rotor and the rotation speed value changes along with the increase of the rotation speed circulation number of the rotor so as to judge whether cracks are generated and spread in the rotation speed circulation process of the rotor; the method for judging whether cracks are initiated in the rotor rotating speed circulation process by the online crack monitoring and analyzing module (4) specifically comprises the following steps: When the test rotor is subjected to a low-cycle fatigue test, a flexible rotor is adopted, the maximum vibration peak value generated in the process of rotor lifting speed appears at the critical rotating speed position, the rotor automatic centering vibration becomes small after the rotor lifting speed exceeds the critical rotating speed, and if the unbalance amount of the rotor is not changed, the maximum vibration amplitude value is stable, so that two regular straight lines can be obtained for each cycle vibration peak value and corresponding rotating speed; When the rotor cracks, the crack opening of the rotor under the action of centrifugal load can cause the unbalance amount of the whole rotor to increase along with the increase of the rotating speed, and the unbalance amount is maximum at the highest rotating speed, the position where the maximum vibration amplitude appears is changed from the critical rotating speed to the highest rotating speed; When the online crack monitoring and analyzing module finds that the position of the vibration peak value jumps back and forth between the critical rotating speed and the highest rotating speed and finally transits to the highest rotating speed, the online crack monitoring and analyzing module determines that crack initiation occurs in the rotor; the method for judging whether the crack is expanded in the rotor rotating speed circulation process by the online crack monitoring and analyzing module (4) comprises the following steps that after the crack is initiated, the online crack monitoring and analyzing module discovers that the vibration peak value of the rotor at the highest rotating speed is continuously increased along with the increase of the circulation number in the rotor rotating speed rising process, and then the online crack monitoring and analyzing module judges that the initiated crack is expanded.
2. 2. The on-line monitoring device for the crack of the test rotor of the vertical rotary tester according to claim 1 is characterized in that the on-line crack monitoring and analyzing module (4) is provided with a test safety module, the on-line crack monitoring and analyzing module gives out an abnormal alarm of the rotor when the vibration peak value of the rotor exceeds a primary limit value of the amplitude set by the tester, and the on-line crack monitoring and analyzing module triggers the shutdown inspection of the tester when the vibration peak value of the rotor exceeds a secondary limit value of the amplitude set by the tester.
3. 3. The on-line monitoring device for the crack of the test rotor of the vertical rotary tester according to claim 1 is characterized in that the vibration sensor (2) is arranged on one side of the rotary main shaft (1) through a sensor bracket, and the key phase sensor (6) is arranged on one side of the rotary main shaft (1) through a sensor bracket.
4. 4. A testing method based on the on-line monitoring device for testing rotor cracks by the vertical rotary tester according to any one of claims 1-3, comprising the following steps: 1) The method comprises the steps of mounting a vibration sensor (2) on one side of a rotating main shaft (1) through a sensor support, mounting a key phase sensor (6) on one side of the rotating main shaft (1) through the sensor support, determining the distance between a sensor probe and a measured object through measuring the strength of eddy current signals, and enabling the vibration sensor to acquire stable eddy current sensing signals through adjusting the radial clearance between the vibration sensor (2) and the outer cylindrical surface of the rotating main shaft (1), wherein the key phase sensor determines that the sensor probe does not pass through a gap arranged on the rotating main shaft and passes through the gap arranged on the rotating main shaft through measuring the existence and disappearance of the electromagnetic sensing signals, adjusts the gap between the key phase sensor (6) and the outer cylindrical surface of the rotating main shaft (1), enables the key phase sensor to acquire stable electromagnetic sensing signals, enables the main shaft to slowly rotate, and enables the key phase sensor to lose the electromagnetic sensing signals when the gap on the main shaft passes through the key phase sensor; 2) The method comprises the steps of respectively connecting a vibration sensor (2) and a key phase sensor (6) with an on-line monitoring system signal processing module (3), connecting the on-line monitoring system signal processing module (3) with an on-line crack monitoring analysis module (4), connecting and debugging the sensor and a signal transmission line under the rotation state of a tester until the sensor and the signal transmission line can normally operate, and enabling the on-line crack monitoring analysis module (4) to complete data recording and analysis work and normally display a graph of vibration amplitude changing along with the rotation speed; 3) The test rotor is installed and connected to the lower end of a driving shaft of the vertical rotary tester, a host power supply of the vertical rotary tester is started, the outer diameter, the axial height, the weight and the rotational inertia of the rotor are set, the target test rotating speed and the load retention residence time are set, then the test rotor is driven to accelerate from zero rotating speed to the target test rotating speed for 30 seconds, and then the test rotor is decelerated and returns to the zero rotating speed, so that whether the vibration sensor (2) and the key phase sensor (6) are affected to fall in the acceleration process of the test rotor is checked, and the maximum vibration amplitude when the critical rotating speed and the over-critical rotating speed are checked and determined is recorded in a book; 4) Starting an online crack monitoring analysis module of the vertical rotation tester test rotor, inputting the outer diameter, the axial height, the weight and the rotational inertia of the rotor, setting an upper limit rotating speed, a lower limit rotating speed, a load-keeping residence time and a target total circulation time, driving the test rotor to rise to the upper limit rotating speed, keeping the load residence time, then reducing the speed to the lower limit rotating speed, keeping the load residence time, continuing to rise the speed, starting to circulate with the same rotating speed waveform, and stopping the machine until the circulation time reaches the target total circulation time; When the online crack monitoring and analyzing module finds that the position of the vibration peak value jumps back and forth between the critical rotating speed and the highest rotating speed and finally transits to the highest rotating speed, the online crack monitoring and analyzing module determines that crack initiation occurs in the rotor; After crack initiation, the online crack monitoring and analyzing module finds that along with the increase of the cycle number, the vibration peak value of the rotor at the highest rotating speed in each cycle speed increasing process is continuously increased, and the online crack monitoring and analyzing module determines that the initiated crack is expanded; when the rotor vibration peak value exceeds the amplitude secondary limit value set by the tester, the online crack monitoring and analyzing module triggers the shutdown check of the tester; after the test is finished, stopping the machine to check the crack initiation position and the expansion length of the test rotor.

Description

Online monitoring device and method for crack of test rotor of vertical rotary tester Technical Field The invention relates to a device and a method for on-line monitoring of cracks of a rotor in a vertical rotary tester, in particular to a device and a method for on-line monitoring and testing of crack initiation and crack propagation of the rotor in a low-cycle fatigue test process of the rotor in the test based on maximum amplitude of the rotor and a rule that a rotating speed value generated when the maximum amplitude changes along with the cycle number, and belongs to the field of low-cycle fatigue tests of aero-engine rotors. Background Modern aeroengines place increasing demands on high thrust-to-weight ratios and long life, forcing engine rotor components to develop toward high strength, long life, low weight. The high-speed rotating part of the aeroengine works under extreme load and severe environment of high temperature, high pressure and high centrifugal force for a long time, and the stress born by the rotor is easy to reach the low cycle fatigue limit of the material due to long-time work and frequent start and stop, so that low cycle fatigue cracks are initiated, and if the low cycle fatigue cracks are further expanded, the rotor is broken. The rotor is a critical component in an aeroengine, and its rupture failure seriously jeopardizes the flight safety. Therefore, the low cycle fatigue problem of the rotor component of the aeroengine is very important for each aviation country, and the low cycle fatigue performance of the rotor component of the aeroengine needs to be strictly inspected in the aspects of design and use management. In testing low cycle fatigue performance of rotor components, particular attention is paid to the monitoring of crack initiation and crack propagation processes. At present, a test method and a principle mainly adopted for crack monitoring in a rotor test are that a vibration original signal of a main shaft system is obtained through an installed vibration sensor, and a zero reference signal of rotor rotation and the rotating speed of the rotor are obtained through an installed key phase sensor. When the rotor is cracked or otherwise abnormal, the unbalance amount and the phase of the rotor system are changed, so that the amplitude peak value and the phase of the rotor system are correspondingly changed, and whether the rotor system has faults such as cracks or other abnormalities or not can be judged by monitoring the changes of the amplitude peak value and the phase of the rotor system. However, the method judges whether the rotor has cracks according to the amplitude peak value and the phase change of the rotor system caused by the unbalance amount and the phase change of the rotor system at the highest rotating speed, and is more suitable for a rigid rotor system. The influence of unbalance change caused by rotor automatic centering on the maximum vibration amplitude of the flexible rotor after the flexible rotor passes the critical rotation speed is small, and an accurate judgment characteristic rule cannot be formed in many cases. Therefore, there is a need for a testing device and a testing method capable of intuitively and accurately performing on-line monitoring of a crack of a test rotor, which can obtain a maximum amplitude of the rotor according to a pulse signal generated by vibration and one rotation of the rotor measured by a sensor, and a graph of a rotation speed value variation with the number of cycles when the maximum amplitude is generated, and infer the initiation and the expansion of the crack according to the variation law, so as to determine whether the crack is initiated and expanded in the rotation speed cycle process of the rotor. When the online crack monitoring and analyzing module finds that an abnormal signal, namely a vibration peak value, gradually increases along with the increase of the cycle number, and the position where the maximum vibration amplitude appears changes from the critical rotating speed to the highest rotating speed and the amplitude exceeds the limit, the online crack monitoring and analyzing module sends out a rotor abnormal alarm prompt, and the online crack monitoring and analyzing module stops to carefully check the crack initiation position and the expansion length of the test rotor. Disclosure of Invention Aiming at the defects of the prior art, the invention creatively realizes the online crack monitoring function of the vertical rotary tester test rotor through the crack online monitoring system, and provides an online monitoring test device and a test method for determining the crack initiation and propagation of the rotor in the low-cycle fatigue process during the fatigue test based on the maximum amplitude of the rotor and the rule of the rotation speed value when the maximum amplitude is generated along with the cycle number. The basic principle of the technical method is that a vibration sensor arra