Patent ID: 7399160

Claim:
A turbine component having a length extending between a root portion and a tip portion; said component having a coolant chamber extending in the direction of said component length; a fluid inlet arranged to feed fluid tangentially into said chamber; a fluid outlet arranged to remove fluid from said chamber; wherein the hydraulic diameter of the coolant chamber at a first point has a length d 1 ; wherein the coolant chamber, at a distance 1 along the chamber from the first point, has a hydraulic diameter d 2 ; and wherein d 1 (1−0.6(½ d 1 ))<= d 2 <=d 1 (1−0.15(½ d 1 )) wherein a fluid supply chamber is located adjacent a leading edge of the component, said fluid inlet arranged to conduct fluid between the fluid supply chamber and the coolant chamber.