Abstract: A new type of flexible gas shaft seal named surface texture padded finger seal is proposed in this paper. An analysis model of the padded finger seal with micro circle surface texture is established. By using the fluid-solid coupling finite element numerical calculation method, the seal’s leakage, gas film lift capacity and gas film flow field characteristics in different working conditions and variable texture parameters are analyzed. It is shown that the finger seal with micro circle surface texture pad has low leakage and high lift capacity. Compared with the existing typical herringbone groove padded finger seal and the contacting finger seal, the surface texture padded finger seal shows a comprehensive advantage. The performance of a surface texture padded finger seal is influenced by the gas pressure to a much greater degree. When the gas pressure is high, increasing the circle diameter, decreasing the depth of the pit, and distributing the micro circle uniformly, will all improve the performance of the seal. The work presented here provides a new way to design finger seals with high performance.

Key words: finger seal, surface texture pad, fluid-solid coupling, leakage, gas film lift capacity