TURBINE ABRADABLE LAYER WITH PROGRESSIVE WEAR ZONE TERRACED RIDGES

摘要

Turbine and compressor casing abradable component embodiments for turbine engines, with composite, non-inflected, bi-angle, “hockey stick” like pattern abradable surface ridges and grooves. Some embodiments include distinct forward upstream and aft downstream composite multi orientation groove and vertically projecting ridges planform patterns, to reduce, redirect and/or block blade tip airflow leakage downstream into the grooves rather than from turbine blade airfoil high to low pressure sides. In some embodiments the grooves are split or divided into multiple sections to interrupt flow traveling inside the groove and cause a local pressurization that reduces tip leakage flow. Some ridge or rib embodiments also have first lower and second upper wear zones. The lower zone optimizes engine airflow characteristics while the upper zone is optimized to minimize blade tip gap and wear by being more easily abradable than the lower zone.