凸起形状对轮缘封严结构燃气入侵的影响

The purpose is to focus on the shape of protrusion near rim seal which was an influential factor on the sealing efficiency. Using the experimental method of measuring CO₂ volume fraction and cavity pressure，the effects of several typical protrusion shapes on sealing efficiency，cavity pressure，cavity flow field and mini⁃ mum sealing flow rate were investigated in order to obtain the optimal shape. The results show that the variation of protrusion shape has little impact on the static pressure in the cavity，and the change of the static pressure near the sealing ring can be neglected. The total pressure and sealing efficiency will increase with the change of protru⁃ sion shape. Installation of protrusion will increase the swirl ratio in the cavity as a whole. When the protrusion shape is hexahedron，the total pressure and sealing efficiency in the cavity are the highest，and the dimensionless minimum sealing flow is reduced by 32% on average compared with the smooth disk.