Compressor airfoils with movable tips

摘要

Aspects of the invention relate to a compressor system for a turbine engine that not only allows for larger compressor blade tip clearances as the engine passes through non-standard operating conditions, but also minimizes clearances during normal engine operation, thereby increasing efficiency of the compressor. The blade assembly can include an airfoil having a movable tip insert recessed within a pocket in the radially distal end of the airfoil. The tip insert can move radially outward from a predetermined recessed position to a predetermined extended position. An abutment surface can be provided within the pocket for engaging the tip insert and/or other associated components so as to limit the extension of the tip insert to the predetermined extended position such that the tip insert does not impinge on the stationary compressor structure and such that a spring operatively associated with the tip insert does not overextend its operational limits.