The physical quantity measured by the sensor is the radial vibration acceleration signal of the rotor in the sealing tester, which is a periodic signal varying with time. Due to the influence of the field environment and error, the signal collected by the sensor is often accompanied by various noises, which will affect the data signal and even submerge some important data signals, resulting in the deviation of signal analysis. Therefore, the time domain synchronous averaging technique is used to separate the useful signals from the data signals mixed with noise, so as to eliminate the interference of unnecessary noise and obtain the corresponding spectrum diagram conveniently.

As shown in the figure, when the seal material is C / C composite material, the time-domain response results of radial vibration acceleration of the rotor in the sealing tester are actually measured at different speeds, and the amplitude frequency characteristics obtained after data processing.

It can be seen from the figure that the radial vibration displacement acceleration of the rotor increases with the increase of the rotor speed. The frequency spectrum shows that the frequency components affecting the vibration characteristics of the rotor are more complex, but on the whole, the rotor rotation frequency is the main frequency component affecting the vibration characteristics.