关键词: 燃油齿轮泵;滑动轴承;稳定性;轴心轨迹;瞬态润滑特性

Abstract: In order to study the transient lubrication behavior of sliding bearings inside aviation fuel gear pump under complex alternating load disturbance, a transient calculation model was established. The model took into account the mass conservation of the oil film cavitation boundary and the influence of the non-linear dynamic load-bearing environment. The combined simulation calculation of fuel gear pump and bearing was realized by batch processing technology, while the effect of transient internal flow field and dynamic load given by fuel pump was considered in the transient calculation process. On this basis, the axis center trajectory stability analysis and transient lubrication performance analysis were carried out. The results show that the error between the calculated results of the bearing model and the experimental data is less than 1.2%. The influence of dynamic load generated by fuel gear pump on bearing axis trajectory is reflected in the increase of trajectory unstable stage offset and the disappearance of static balance position. Comparative studies predict that the equilibrium position is superior for a bearing with higher width-diameter ratio or smaller clearance ratio. When the clearance ratio increases from 0.2% to 0.6%, the change trend of the axis position in the unstable stage changes from double peak to single peak, and the fluctuation amplitude of the curve in the velocity stable section increases first and then tends to remain unchanged. When the aspect ratio increases from 0.6 to 1.2, the deviation of the velocity response curve decreases in full cycle. In the transient lubrication characteristics of bearings, the sensitivity of the leakage flow rate to bearing load variation is strong, while the minimum oil film thickness is poor.

Key words: Fuel gear pump;Sliding bearing;Stability;Axis center trajectories;Transient lubrication characteristics