Patent ID: 8844936
Filing Date: 2014-09-30
Classification: F01D,F16J

Abstract:
1. A seal, comprising: first and second axial ends; a hollow member having an inner surface extending between the first and second axial ends, the hollow member having a longitudinal axis extending between the first and second axial ends, wherein the hollow member is cylindrical; and a plurality of depressions formed in the inner surface, each of the plurality of depressions having a depth measured from the longitudinal axis towards a bottom of the plurality of depressions inside the hollow member, the depths of the plurality of depressions progressively varying as proceeding away from the first axial end toward the second axial end as a function of axial distance from the first axial end, the function of the axial distance is an exponential function, a sinusoidal function, or a square root function.