System and method to eliminate a hard rub and optimize a purge flow in a gas turbine

[0017]As discussed in detail below, embodiments of the present invention include a system and method to eliminate a hard rub and optimize a purge flow in a gas turbine. In one embodiment, the system includes an angel wing without a tip that eliminates the hard rub between the angel wing and a discourager. As referred to herein, the term ‘hard rub’ is defined as a rub during startup of the turbine between metal components of the angel wing tip and the discourager. Furthermore, a fan blade is disposed on the angel wing that generates a recirculation zone of the purge flow to reduce a volume of successive purge flows entering a wheel space. As used herein, the term ‘purge flow’ is defined as a gas flow entering the wheel space from a clearance area to prevent overheating and to maintain an acceptable temperature in the wheel space. As referred to herein, the ‘clearance area’ is defined as a gap between the discourager and the angel wing. In another embodiment, the angel wing tip is ret...