TURBINE ABRADABLE LAYER WITH AIRFLOW DIRECTING PIXELATED SURFACE FEATURE PATTERNS

摘要

A turbine abradable component includes a support surface and a thermally sprayed ceramic/metallic abradable substrate coupled to the support surface for orientation proximal a rotating turbine blade tip circumferential swept path. An elongated pixelated major planform pattern (PMPP) of a plurality of discontinuous micro surface features (MSF) project from the substrate surface. The PMPP repeats radially along the swept path in the blade tip rotational direction, for selectively directing airflow between the blade tip and the substrate surface. Each MSF is defined by a pair of first opposed lateral walls defining a width, length and height that occupy a volume envelope of 1-12 cubic millimeters. The PMPP arrays of MSFs provide airflow control of hot gasses in the gap between the abradable surface and the blade tip with smaller potential rubbing surface area than solid projecting ribs with similar planform profiles.