Patent ID: 8764380

Claim:
A rotor blade for a turbo machine, comprising: an aerofoil having pressure and suction surfaces, leading and trailing edges; and an array of passages at a tip region of the aerofoil, wherein the passages extend from the pressure surface to the suction surface of the aerofoil and are disposed so that the array creates, in operation, individual jets of gas which exit the passages and coalesce at a point to form a coherent jet of gas issuing from the suction surface, the jet being inclined outwardly from the suction surface and towards the tip, and in the direction from the leading edge to the trailing edge, and wherein at least 50% of the passage outlets, are situated at a distance from the tip which is not less than 1% and not more than 25% of the span of the aerofoil and at least 50% of the passage outlets, are situated at a distance not more than 25% of the chord of the aerofoil from the leading edge.