Variable area cooled airfoil construction for gas turbines

Claim 1

A cooled airfoil for gas turbines, comprising: a. impervious body means forming an airfoil with a rounded leading edge, a relatively narrow trailing edge and curved sides connecting said edges, the body walls being of predetermined substantially uniform thickness and providing said airfoil with an internal chamber, the body having at least one outlet opening in the trailing edge; b. tubular insert means of similar airfoil shape disposed in the internal chamber of said body for receiving a cooling medium under pressure, said tubular means having a slot in the forward wall adjacent the leading edge of the body means for directing a stream of cooling medium against the inner surface of the leading edge wall; c. a first set of fins elements projecting from the inner surfaces of the body sidewalls into engagement with the outer surfaces of said tubular insert means, the fins of said first set extending transversely of the sidewalls and being spaced longitudinally of said body to form cooling fluid conducting passages extending chordwise of the airfoil to establish communication between the slot in the tubular means and the outlet opening in the trailing edge of the body means; and d. a second set of fin elements projecting from the inner surfaces of the body sidewalls in the spaces between the fins of the first set, the fins of the second set terminating in spaced relation from the tubular means and being of variable height to form heat exchange surfaces of predetermined variable area disposed to provide a selected temperature distribution over the sidewalls of said body.