Non-contact seal shoe with diffuser structure

An apparatus for rotational equipment, comprising:

• a seal device including a plurality of seal shoes, a seal base and a plurality of spring elements;
• the plurality of seal shoes arranged circumferentially around an axis in an annular array, the plurality of seal shoes comprising a first seal shoe that includes a seal surface and a diffuser surface, and the seal surface extending axially along the axis to an axial interface location where the seal surface axially meets the diffuser surface, wherein a minimum radius of the first seal shoe measured from the axis to the seal surface is defined at least at the axial interface location, and a diffuser radius measured from the axis to the diffuser surface increases as the diffuser surface extends axially along the axis from the interface location to an axial distal side of the first seal shoe;
• the seal base extending circumferentially around the axis;
• and
• the plurality of spring elements connecting and extending between the annular array of the plurality of seal shoes and the seal base;
• wherein the first seal shoe further includes a shoe base, a tooth, a diffuser and a groove;
• wherein the axial distal side of the first seal shoe is a second axial distal side of the first seal shoe, and the shoe base extends axially along the axis between a first axial distal side of the first seal shoe and the second axial distal side of the first seal shoe;
• wherein the tooth projects radially out from the shoe base towards the axis;
• wherein the diffuser projects radially out from the shoe base, towards the axis, to the seal surface and the diffuser surface;
• and
• wherein the groove extends axially between and is formed by the tooth and the diffuser.

An apparatus for rotational equipment, comprising:

• a seal device including a plurality of seal shoes, a seal base and a plurality of spring elements;
• the plurality of seal shoes arranged circumferentially around an axis in an annular array, the plurality of seal shoes comprising a first seal shoe that includes a shoe base, a tooth, a diffuser structure and a groove, the shoe base extending axially along the axis between a first axial distal side of the first seal shoe and a second axial distal side of the first seal shoe, the tooth projecting radially out from the shoe base towards the axis to a tooth seal surface, the diffuser structure projecting radially out from the shoe base towards the axis to a diffuser surface, the diffuser surface extending axially from a location on a radial inner distal side of the diffuser structure to the second axial distal side of the first seal shoe, the diffuser surface angularly offset from the axis by an offset angle less than ten degrees, and the groove extending axially within the first seal shoe between and formed by the tooth and the diffuser structure;
• the seal base circumscribing the annular array of the plurality of seal shoes;
• and
• the plurality of spring elements comprising a first spring element, and the first spring element connecting and extending between the first seal shoe and the seal base.