The Effect of High Frequency Pressure Pulse on the Friction and Leakage Performance of Seals in Aviation Hydraulic Cylinders

The hydraulic system generates strong fluid pulses when hydraulic valves, hydraulic pump switches, and load changes. This paper takes the seals of aviation actuators as the research object, the friction and leakage characteristics of reciprocating seals under pressure pulse were studied based on a multi working condition simulation test bench for reciprocating seals. To investigate the impact of pulse frequency on seal leakage, the characteristics of the seals under a sinusoidal pressure pulse of 0-2Hz were discussed. The influence of pulse frequency and waveform on the sealing friction characteristics under high pressure was also studied. The experimental results showed that the leakage of the seal shows a gradually increasing trend as the pulse frequency increases. Besides, the sealing friction characteristics were significantly affected by the pulse waveform, and the sealing friction curve would undergo significant changes with the change of the pulse waveform.