Patent attributes
Aspirating face seal between high and low pressure regions of turbomachine between rotatable and non-rotatable members of turbomachine includes gas bearing rotatable and non-rotatable face surfaces, starter tooth mounted on the rotatable member operable to sealingly engage abradable starter seal land on the non-rotatable member, and annular pocket in an abradable coating or other abradable material of starter seal land. Abradable material may be in radially inwardly facing groove extending into non-rotatable member. Pocket may extend radially outwardly from a cylindrical radially outer abradable surface to pocket bottom which includes thin abradable material layer groove surface along the non-rotatable member. Pocket may extend axially aftwardly from annular forward groove side surface into abradable coating. Pocket may be bounded axially by abradable material. Pocket may be tapered having taper decreasing axially aftwardly away from annular forward groove side surface.
