| 摘要 |
A turbine blade with a stepped tip rail extending along the pressure side and the suction side of the blade tip, the stepped tip rail having tip cooling holes in the stepped portion of the tip rail to provide cooling and sealing for the blade tip. The walls of the airfoil include near wall cooling holes that open into a collector cavity formed on the backside of the tip and direct cooling air onto the backside of the tip to provide impingement cooling. The spent air from the near wall cooling holes is collected in the cavity and then discharged out the tip cooling holes. The tip cooling holes are offset inward from the near wall cooling holes to enhance the backside impingement cooling of the tip. |
