# US 2014/0154096 A1 · Turbine blade airfoils including showerhead film cooling systems, and methods for forming an improved showerhead film cooled airfoil of a turbine blade > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0154096 A1 - Document ID: US20140154096A1 - Status: Published application - Kind: A1 - Application number: 13/692,353 - Filed: 2012-12-03 - Published: 2014-06-05 - Earliest claimed: 2012-12-03 - Assignees: Honeywell International Inc. - Applicants: Honeywell International Inc. - Inventors: Vighneswara Rao Kollati; Balamurugan Srinivasan; Jong Liu; Daniel Cregg Crites; Luis Tapia; Malak Fouad Malak; Rajiv Rana - Web page: https://patentgrep.com/patent/US20140154096A1 ## CPC - F01D 5/186: {Film cooling (F01D5/187 takes precedence)} - F01D 5/187: {Convection cooling} - F05D 2260/202: by film cooling - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - Y10T 29/49341: with cooling passage - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Turbine blade airfoils, showerhead film cooling systems thereof, and methods for cooling the turbine blade airfoils using the same are provided. The airfoil has a leading edge and a trailing edge, a pressure sidewall and a suction sidewall both extending between the leading and the trailing edges, and an internal cavity for supplying cooling air. A showerhead of film cooling holes is connected to the internal cavity. Each film cooling hole has an inlet connected to the internal cavity and an outlet opening onto an external wall surface at the leading edge of the airfoil. A plurality of surface connectors is formed in the external wall surface. Each surface connector of the plurality of surface connectors interconnects the outlets of at least one selected pair of the film cooling holes. ## Claims ### Claim 1 An airfoil of a turbine blade, the airfoil comprising: a leading edge and a trailing edge; a pressure sidewall and a suction sidewall both extending between the leading and the trailing edges; an internal cavity for supplying cooling air; a showerhead of film cooling holes connected to the internal cavity, each film cooling hole having an inlet connected to the internal cavity and an outlet opening onto an external wall surface at the leading edge of the airfoil; and a plurality of surface connectors formed on the external wall surface, each surface connector of the plurality of surface connectors interconnecting the outlets of a selected pair of the film cooling holes. ### Claim 2 (depends on 1) The airfoil of claim 1, wherein the showerhead of film cooling holes comprises at least three rows of film cooling holes with one of the rows comprising a first plurality of film cooling holes extending in a span-wise direction of the airfoil and located substantially along a stagnation line of the leading edge, the at least three rows of film cooling holes further comprising: a second plurality of film cooling holes extending in a span-wise direction of the airfoil and in the pressure sidewall at the leading edge; and a third plurality of film cooling holes extending in a span-wise direction of the airfoil and in the suction sidewall at the leading edge. ### Claim 3 (depends on 2) The airfoil of claim 2, wherein the first plurality of film cooling holes is staggered in the span-wise direction from the second and third plurality of film cooling holes, the second and third plurality of film cooling holes being substantially horizontally aligned. ### Claim 4 (depends on 2) The airfoil of claim 2, wherein the plurality of surface connectors is selected from the group consisting of span-wise connectors, cross-wise connectors, and both span-wise and cross-wise connectors. ### Claim 5 (depends on 4) The airfoil of claim 4, wherein each span-wise connector extends in a span-wise direction between the outlets of the selected pair of the film cooling holes, the selected pair of the film cooling holes comprising sequential film cooling holes within the same cooling row. ### Claim 6 (depends on 4) The airfoil of claim 4, wherein each cross-wise connector extends between adjacent outlets of the selected pair of film cooling holes in adjacent cooling rows. ### Claim 7 (depends on 4) The airfoil of claim 4, wherein each cross-wise connector extends between the outlet of a film cooling hole in the pressure sidewall at the leading edge and the outlet of an adjacent film cooling hole at the stagnation line, between the outlet of the a film cooling hole in the suction sidewall at the leading edge and the outlet of the adjacent film cooling hole at the stagnation line, or both. ### Claim 8 A showerhead film cooling system for an airfoil of a turbine blade, the system comprising a showerhead of film cooling holes arranged in cooling rows at a leading edge of the airfoil, each film cooling hole having an inlet and an outlet, the outlet opening onto an external wall surface at the leading edge; and a plurality of surface connectors on the external wall surface of the airfoil for interconnecting selected outlets of the film cooling holes to provide a coolant path between them. ### Claim 9 (depends on 8) The showerhead film cooling system of claim 8, wherein the showerhead of film cooling holes comprises at least three rows of film cooling holes with one of the rows comprising a first plurality of film cooling holes extending in a span-wise direction of the airfoil and located substantially along a stagnation line of the leading edge, the at least three rows of film cooling holes further comprising: a second plurality of film cooling holes extending in a span-wise direction of the airfoil and in the pressure sidewall at the leading edge; and a third plurality of film cooling holes extending in a span-wise direction of the airfoil and in the suction sidewall at the leading edge. ### Claim 10 (depends on 9) The showerhead film cooling system of claim 9, wherein the first plurality of film cooling holes is staggered in the span-wise direction from the second and third plurality of film cooling holes, the second and third plurality of film cooling holes being substantially horizontally aligned. ### Claim 11 (depends on 10) The showerhead film cooling system of claim 10, wherein the plurality of surface connectors is selected from the group consisting of span-wise connectors, cross-wise connectors, and both span-wise and cross-wise connectors. ### Claim 12 (depends on 11) The showerhead film cooling system of claim 11, wherein each span-wise connector extends in a span-wise direction between the outlets of the selected pair of the film cooling holes, the selected pair of the film cooling holes comprising sequential film cooling holes within the same cooling row. ### Claim 13 (depends on 12) The showerhead film cooling system of claim 12, wherein each cross-wise connector extends between adjacent outlets of the selected pair of film cooling holes in adjacent cooling rows. ### Claim 14 (depends on 13) The showerhead film cooling system of claim 13, wherein each cross-wise connector extends between the outlet of a film cooling hole in the pressure sidewall at the leading edge and the adjacent outlet of a film cooling hole at the stagnation line, between the outlet of the film cooling hole in the suction sidewall at the leading edge and the adjacent outlet of the film cooling hole at the stagnation line, or both. ### Claim 15 A method of forming an improved showerhead film cooled airfoil of a turbine blade comprising the steps of: providing an airfoil of a turbine blade having a showerhead of film cooling holes in a leading edge, each film cooling hole having an inlet and an outlet, the outlet opening onto an external wall surface of the leading edge; and forming a plurality of surface connectors on the external wall surface for interconnecting the outlets of at least one selected pair of film cooling holes. ### Claim 16 (depends on 15) The method of claim 15, wherein the step of forming a plurality of surface connectors comprises forming a plurality of span-wise connectors, each span-wise connector extending in a span-wise direction between the outlets of a selected pair of sequential film cooling holes within a cooling row. ### Claim 17 (depends on 16) The method of claim 16, wherein the step of forming a plurality of surface connectors further comprises forming a plurality of cross-wise connectors, each cross-wise connector extending between adjacent outlets of the selected pair of film cooling holes in adjacent cooling rows. ### Claim 18 (depends on 15) The method of claim 15, wherein the step of forming a plurality of surface connectors comprises forming a plurality of cross-wise connectors, each cross-wise connector extending between adjacent outlets of a selected pair of adjacent film cooling holes in adjacent rows. ### Claim 19 (depends on 15) The method of claim 15, wherein a first plurality of film cooling holes at a stagnation line is staggered from a second and a third plurality of film cooling holes, and wherein the step of forming a plurality of surface connectors comprises forming a plurality of cross-wise connectors, each cross-wise connector extending and inclined between the outlet of a film cooling hole in the pressure sidewall at the leading edge, in the suction sidewall at the leading edge, or both and the outlet of an adjacent film cooling hole at the stagnation line. ### Claim 20 (depends on 15) The method of claim 15, wherein the step of forming a plurality of surface connectors comprises integrally forming the plurality of surface connectors in a material of the turbine blade at the leading edge.