Abstract: A component such as a turbine blade of a gas turbine engine includes a film cooling arrangement which is optimised by a process in which a component is manufactured having a film cooling arrangement of an initial design and evaluation of the performance of the film cooling arrangement is conducted, for example on the basis of the blowing rate of cooling holes present in the initial design. The configuration of a cooling hole of the initial design is subsequently modified in order to improve the performance of the film cooling arrangement and a component is manufactured in accordance with the modified design. By way of example, the initial design may provide a single cooling hole 128 and the modification may comprise the provision of additional cooling holes 126, 130, each intersecting the initial cooling hole 128 adjacent its inlet end which opens into a source of cooling fluid 120.

Abstract: A component such as a turbine blade for a gas turbine engine has a cooling arrangement comprising a supply passage 18 within the blade from which extend cooling passages 28 of a first array which open at discharge openings 29, for example at a trailing edge of the blade. Cooling passages 30 of a second array extend into the blade from discharge openings 31, and intersect the passages 28. The passages 30 terminate short of the supply passage 18. As a result of this arrangement, the limiting flow area for cooling air is defined by the cooling passages 28 of the first array, and is not affected by the accuracy with which the cooling passages 30 of the second array intersect the cooling passages 28 of the first array.