Patent ID: 9121610
Filing Date: 2015-09-01
Classification: F23M,F23R

Abstract:
1. A combustor casing, comprising: an inner casing defining a combustion chamber; an outer casing spaced apart from the inner casing for defining a passage between the inner and the outer casing, the passage being adapted to guide cooling air from a cooling air entrance arranged at a downstream end of the combustion chamber to a burner hood arranged at an upstream end of the combustion chamber; first and second effusion holes arranged in the inner casing, through which a portion of the cooling air penetrates into the combustion chamber; and dividing ribs connecting the inner casing and outer casing and forming first and second volumes for receiving part of a flow injected into the passage, wherein the dividing ribs are separate from one another and are not equally spaced to form the first and second volumes, wherein the first effusion holes are arranged in the first volume and the second effusion holes are arranged in the second volume, and wherein the first effusion holes have a first pattern and the second effusion holes have a second pattern, such that the first and second patterns differ in terms of hole diameters and/or spacing between the holes, and wherein the first and second volumes, as well as the hole diameters and/or spacing between the holes are adapted to specific frequencies to optimise damping performance and differ between different volumes.