Study On Sealing Performance Of Composited Elastic Metal Sealing Ring Used On Aircraft Engine

With the continuous improvement of the technology and performance requirements of aeroengine,the problem of seal has become the research hotspot in aeroengine field.The seal working conditions of aeroengine firstly have to satisfy the characteristics of the fluid mechanical rotor system,secondly,withstand high temperature,high differential pressure and deformation caused by excessive vibration. The main form of the seal includes the dynamic seal and the static seal. The sealing ring is an important component of sealing structure, its mechanical properties have a directly influence on the sealing effect. In this paper, the elastic piece is a kind of special axial self tightening type metal sealing ring. It is an important seal structure in high pressure turbine area of aeroengine.This paper mainly includes the finite element simulation and the seal leakage experiment of elastic piece two parts. Firstly, the finite element analysis model is established according to the basic structure of the composite elastic piece metal sealing ring,and nalysis of the expansion stress and sealing characteristics : including the effect of compression of different elastic piece on the Mises Von stress; the influence of different elastic piece compression on its sealing performance. The calculation results show that the increase of the compression quantity in the yield limit of the elastic piece is beneficial to the improvement of the sealing performance of the structure. Elastic piece structure in the case of non working pressure or lower pressure, the top block and the sealing piece is not completely contact, can not play a sealing effect. But in the case of higher working pressure, the compression angle between 9degrees-7 degrees, the top block and the sealing piece is completely exposed, and the sealing effect is good. Secondly,dynamics feature of the composited elastic metal sealing ring is analyzed,such as model analysis,harmonic analysis. Its natural frequencies under different constraints obtained by modal analysis; Through harmonic response analysis to obtain the steady-state response under harmonic excitation.In experimental aspect, the influence of chamber pressure and elastic piece compression on the leakage rate of the seal structure and the influence of the cavity pressure on the leakagearea of the elastic sheet is studied. The results show that the leakage rate increases linearly with the increase of pressure in the chamber. Chamber pressure to the elastic piece structure to establish a certain sealing effect, the greater the pressure when the sealing effect is better, the greater the compression amount of the elastic film increases the sealing performance is not significant. In the case of low compression or low chamber pressure, the main leakage mode is the contact leakage. When the compression quantity or the chamber pressure increases to a certain value, the main leakage way is the channel leakage, and the leakage area of the channel is 169mm2.