Patent ID: 8109726

Claim:
A turbine airfoil, comprising: a generally elongated, hollow airfoil formed by an outer wall extending chord wise from a forward leading edge to a rearward trailing edge, a tip section at a first span wise end, a root coupled to the airfoil at an end generally opposite the first end span wise for supporting the airfoil and for coupling the airfoil to a disc, and a cooling system formed from at least one cavity in the elongated, hollow airfoil positioned in internal aspects of the generally elongated, hollow airfoil; said outer wall having a concave pressure side and a convex suction side separated rearwardly by the trailing edge; said at least one cavity forming a multi-pass serpentine flow circuit with each pass extending span wise and connecting chord wise at a turn with an adjacent pass and providing a flow path from a forward cooling flow entry at the root and exhausting towards the trailing edge; a series of chord wise micro channels extending from the rearward pass of the multi-pass serpentine circuit to pressure side bleed slots, each having a forward pressure side lip and opening onto the pressure side adjacent the trailing edge, said micro channels being formed by a series of spaced fins stacked span wise and extending between the outer wall on the pressure side and the outer wall on the suction side and extending chord wise from the rearward pass to the trailing edge; and at least two trip strips extending from sides of the fins into the micro channels, whereby turbulent flow levels in the micro channels are increased.