Gas turbines airfoils such as nozzles are subjected to intense heat and external pressures in the hot gas path. These rigorous operating conditions are exacerbated by advances in the technology, which may include both increased operating temperatures and greater hot gas path pressures. As a result, gas turbine airfoils are sometimes cooled by flowing a fluid through a manifold inserted into the core of the airfoil. The fluid then exits the manifold through impingement holes into a post-impingement cavity, and subsequently exits the post-impingement cavity through apertures in the exterior wall of the airfoil, forming a film layer of the fluid on the exterior of the airfoil.
However, crossflow in the post-impingement cavity, and non-optimized flow paths inhibit fluid cooling in the post-impingement cavity. The rigorous operating conditions, materials and manufacturing techniques have maintained or even exacerbated crossflow in the post-impingement cavity, laminar flow of the cooling fluid and non-optimized flow paths.