Abstract:In order to solve the problem of oil leakage in the lubricating oil chamber of CFM56 series engine at low speed,the numerical simulation of labyrinth seal was carried out by using volume of fluid(VOF)two-phase flow theory.The effects of structural parameters such as tooth number,tooth pitch,tip clearance,tooth height,tooth tip width and tooth angle on the leakage of lubricating oil were analyzed.The results show that the leakage of lubricating oil increases obviously with the increase of tooth tip clearance.When the tooth top clearance is from 0.3 mm to 0.4 mm,the increasing trend of leakage is more obvious.The tooth pitch has little effect on the leakage,and the leakage of lubricating oil increases slightly with the increase of tooth pitch.The leakage decreases obviously with the increase of tooth angle,especially when the tooth angle is less than 90°.The leakage first increases and then decreases with the increase of tooth tip width.The leakage decreases with the increase of the tooth number.When the tooth number is 2 to 4,the leakage decreases obviously,and the change tends to stable when the tooth number is higher than 4.Taking the minimum leakage of labyrinth seal as the goal,the response surface method was used to optimize the multi-objective parameters.After optimization,the lubricating oil leakage is reduced by 87.5%.