Internal cooling of turbine airfoil wall using mesh cooling hole arrangement

In a turbine blade airfoil having leading and trailing edge portions and opposite side walls defining pressure and suction sides and extending between and merging together with said leading and trailing edge portions, said side walls having internal surfaces defining a hollow interior chamber for communication of cooling air flow to said side walls, said side walls having external surfaces spaced from said internal surfaces and extending generally in the direction of gas flow past said airfoil from said leading edge portion to said trailing edge portion of said airfoil, each of said side walls having an interior structure defined between said internal and external surfaces thereof, a mesh cooling hole arrangement comprising:

• (a) first and second pluralities of cooling holes formed within said interior structure of each of said side walls of said airfoil so as to extend between and along but not intersect with said spaced internal and external surfaces of said side walls extending between said leading and trailing edge portions of said airfoil, said cooling holes of each of said pluralities extending generally parallel to one another;
• (b) said cooling holes of said first plurality and said cooling holes of said second plurality having inlets and outlets disposed such that the cooling flow direction within said cooling holes is in a generally axial direction from said leading edge portion to said trailing edge portion of said airfoil;
• and
• (c) said cooling holes of said first plurality intersecting said cooling holes of said second plurality so as to define a plurality of spaced apart internal solid nodes in said side walls having pairs of opposite sides interconnected by pairs of opposite corners, a multiplicity of hole portions extending between and along opposite sides of adjacent nodes and a plurality of flow intersections interconnecting said hole portions and disposed between said corners of adjacent nodes;
• (c) said sides of said internal nodes in said side walls of said airfoil having lengths greater than the widths of said hole portions between adjacent nodes such that when cooling fluid is passed through said first and second pluralities of cooling holes in said airfoil side walls a jet flow action is created in said hole portions between said sides of adjacent nodes which generates jet interactions at said flow intersections between said corners of adjacent nodes to cause restriction of air flow and produce a pressure drop, enhancing convective heat transfer between said airfoil side walls and the cooling air.