航空发动机二级滑油泵地面及高空特性试验

Taking a two-stage lubricating oil pump for a specific aero-engine as the object，a testing system was developed to evaluate the flow performance under pure oil medium， meeting the test requirements of the oil pump. Performance tests under pure oil medium were conducted to explore the high-altitude performance of the pump and analyze the impact of various operating parameters on the flow performance of the lubricating oil pump. The results indicated that the volumetric efficiency of the two-stage pump fluctuated by less than 5% with changes in outlet pressure，with the rotational speed ranging from 1 003 to 4 014 r/min， and outlet pressure below 600 kPa in the ground tests. The oil flow rate demonstrated a linear relationship with rotational speed，increasing in conjunction with the rotational speed，while volumetric efficiency declined. During high-altitude tests，the oil flow rate and volumetric efficiency of the second-stage pump exhibited a slight increase compared with those of the first-stage pump at varying inlet pressures. The oil flow rate and volumetric efficiency of the two-stage pump significantly declined with the reduction in inlet pressure. The oil flow rate and volumetric efficiency of the two-stage pump exhibited a significant decrease at flight altitudes below 8 km. With the increase of rotational speed，the decrease in oil flow rate and volumetric efficiency accelerated. The volumetric efficiency remained below 50% at all rotational speeds until reaching a flight altitude of 12 km.