Turbine blade tip shroud

A turbine blade tip shroud, comprising:

• a plate on a tip of a turbine blade;
• a seal rail oriented in a circumferential direction of rotation relative to a turbine axis, the seal rail extending radially outward from the plate relative to the turbine axis;
• a first tooth forming a lateral bump on a downstream side of the seal rail with respect to a working gas flow, the first tooth comprising a sharp top leading edge;
• a second tooth forming a lateral bump on an upstream side of the seal rail with respect to the working gas flow, the second tooth comprising a sharp top leading edge;
• the seal rail comprising a front portion ahead of the first tooth with respect to the direction of rotation and a back portion behind the second tooth with respect to the direction of rotation, wherein the back portion of the seal rail spans linearly from a lateral peak of the second tooth to a back end of the seal rail that is centered on an extended centerline of the front portion of the seal rail.

A turbine blade tip shroud, comprising

• a seal rail oriented in a circumferential direction of rotation relative to a turbine axis, and extending radially outward from the shroud relative to the turbine axis;
• and
• a first tooth and a second tooth extending from the seal rail respectively downstream and upstream with respect to a working gas flow, the first and second teeth forming a continuously smooth comma-shaped transition between a front portion of the seal rail and a back portion thereof as viewed from above;
• wherein the back portion of the seal rail spans linearly from an upstream peak of the second tooth to a back end of the seal rail that is centered on an extended centerline of the front portion of the seal rail.