The disclosure pertains to a cooled wall for separating a hot gas flow path of a gas turbine from a cooling flow including at least one turbulator rib extending from the wall into the cooling flow, and having a height, a width for providing heat transfer enhancement for the cooled wall. The turbulator rib has filets at its root with a filet radius. In order to increase the heat transfer enhancement of the turbulator rib, the filet at the downstream side of turbulator rib is extending into the cooled wall with a penetration depth. Further, the disclosure relates to specific embodiments in which the cooled wall with turbulator ribs is configured as the sidewall of an airfoil, a combustor wall or a heat shield.
1. A wall of a gas turbine for separating a hot gas flow path from a cooling gas flow path, the wall comprising:
a surface facing the cooling gas flow path;
at least one turbulator rib extending from the surface of the wall into the cooling gas flow path;
wherein each at least one turbulator rib includes a root at a connection of each turbulator rib to the surface of the wall, each root having a fillet arranged on a downstream side of the respective turbulator rib relative to a cooling gas flow direction during operation and a fillet arranged on an upstream side of the respective turbulator rib relative to the cooling gas flow direction during operation;
each downstream fillet has a radius and forms an indentation in the surface of the wall, wherein each indentation forms a local reduction in thickness of the wall, and wherein a transition surface of the surface of the wall extend linearly from each downstream fillet toward the upstream fillet of an adjacent turbulator rib of the at least one turbulator ribs.
2. The wall according to claim 1 , wherein each transition surface has a curved portion distal to the adjacent downstream fillet that is curved with a curvature, which is greater than a curvature of the radius of each downstream fillet.
3. The wall according to claim 1 , wherein the entirety of each transition surface is linear.
4. The wall according to claim 1 , wherein each downstream fillet has a radius and penetrates into the wall with a penetration depth between 0.5 and 1.5 times each downstream fillet radius.
5. The wall according to claim 1 , wherein a penetration depth of each downstream fillet extending into the wall is smaller than each downstream fillet radius.
6. The wall according to claim 1 , wherein a penetration depth of each downstream fillet extending into the wall is less than ¼ of the wall thickness.
7. The wall according to claim 1 , wherein the at least one turbulator rib has a width and at least two of the at least one turbulator rib are arranged with a pitch therebetween and the width is 5% to 20% of the pitch.
8. The wall according to claim 1 , wherein the cooling gas flow path comprises a cooling flow passage and a height of the at least one turbulator rib is between 5% and 20% of a height of the cooling flow passage.
9. The wall according to claim 1 , wherein the at least one turbulator rib is an integral part of the wall and/or in that the wall and the at least one turbulator rib is one cast part.
10. The wall according to claim 1 , wherein the wall is a sidewall of an airfoil having a first sidewall and an opposite second sidewall joined together at a leading edge and a trailing edge and extending longitudinally from a root to a tip, and the cooling gas flow path comprises an internal cooling flow passage that extends longitudinally between said first and second sidewalls for channeling a cooling medium to cool the airfoil.
11. A heat shield in the hot gas flow path of the gas turbine comprising:
the wall according to claim 1 .
12. A sidewall of a burner or a combustion chamber of the gas turbine, comprising:
the wall according to claim 1 .