Analysis of the influence of lubricant supply conditions on the pressure distribution in squeeze-film dampers

Abstract

One of the most common ways to reduce vibration in aircraft engines is the use of damping devices. Squeeze-film dampers are the dampers most widely used in aircraft engine designs. The efficiency of squeeze-film dampers is determined by their damping capacity which depends, among other parameters, on the static pressure of oil supply to the damper. This article proposes a method for calculating the static pressure in the feed groove of a hydrodynamic damper depending on the geometric size of the end gap and the value of the lubricant supply pressure. The parameters influencing the static pressure in the damper end gap are determined. Calculations are performed for different values of a hydrodynamic damper end gap, the number and diameter of the supply ports. All calculations presented in the article were performed for a short squeeze-film damper with end gaps and throttles. For comparison of parameters, the dynamic pressure was also calculated for a long squeeze-film damper. It was shown that the size of the end gap has the strongest impact on the pressure in the groove of a squeeze-film damper. It was also shown that the dynamic pressure in the gap may be significantly higher than the static pressure of supply, and failure of the lubricating film may result. In addition, it was also shown that the size of the damper end clearance affects the lubricant flow through the damper.