Hydrodynamic non-contacting seal

In a bearing compartment for a gas turbine engine having a rotor shaft adapted for support on bearings, a hydrodynamic non-contacting face seal comprising:

• a stationary seal ring having a continuous sealing surface disposed in a higher fluid pressure region of said bearing compartment;
• a rotatable seal plate mounted on said shaft in a lower pressure region of said bearing compartment, said rotatable seal plate having a grooved sealing surface opposed to and in close proximity to the sealing surface of said stationary seal ring;
• said sealing surface grooves in said sealing surface of said rotatable seal plate being disposed in a spiral pattern;
• each of said grooves having a width and a depth wherein the depth of each of said grooves decreases across the width thereof in a direction opposite to the direction of rotation of said rotatable seal plate;
• wherein the rotatable seal plate extends radially between an inner surface and an outer surface, and each of the grooves extends radially into the rotatable seal plate from an edge of the inner surface;
• and
• wherein each of the grooves includes a pair of opposing sidewalls and a bottom wall, each sidewall has an inner edge and a height, and the bottom wall extends between the sidewalls at the inner edges thereof, and wherein the depth extends between the bottom wall and the grooved sealing surface.

A hydrodynamic non-contacting seal comprising:

• a stationary seal member having a sealing surface;
• a rotatable seal member forming a seal with the stationary seal member and having a radially inner radius and a radial expanse, a sealing surface of the rotatable seal member opposing the sealing surface of the stationary seal member;
• the rotatable seal member adapted for rotation in a first circumferential direction and including, in the sealing surface thereof, a radially outwardly extending spiral pattern of grooves, each of said grooves having a width and a depth;
• wherein the depth of each of the grooves decreases across the width thereof in a direction opposite to the circumferential direction of rotation of the rotatable seal member;
• and
• wherein a first of the grooves includes a pair of opposing sidewalls and a bottom wall, each sidewall has an inner edge and a height, and the bottom wall extends between the sidewalls at the inner edges thereof, and wherein the depth extends between the bottom wall and the sealing surface of the rotatable seal member.