Patent ID: 7520724

Claim:
A cooled blade for a gas turbine, the blade comprising: a blade airfoil extending in a spanwise direction from a blade base and a blade shank to a blade tip, the blade airfoil having a leading edge and a trailing edge; a plurality of coolant ducts arranged inside the blade airfoil, the coolant ducts being arranged serially in a flow direction, and extending in an spanwise direction of the blade airfoil from the blade shank region to the blade tip, a first of said coolant ducts extending along the leading edge and a second of said coolant ducts extending along the trailing edge, the first and second coolant ducts being arranged and adapted for passing a main flow of a coolant through them in the spanwise direction towards the blade tip; an inlet of the first coolant duct connected with a main coolant inlet; an outlet of the first coolant duct fluidly connected to an inlet of the second coolant duct via a first deflection region; at least one third coolant duct arranged between the first and the second coolant ducts and a second deflection region, the second deflection region being arranged between the third coolant duct and the second coolant duct; and an orifice extending from the main coolant inlet to the second deflection region which is constructed and arranged to provide supplemental flow of coolant into a heated main coolant flow flowing from the third coolant duct towards the second coolant duct, wherein the orifice is angled obliquely upward relative to the axial direction.