Multiple wall impingement plate for sequential impingement cooling of an endwall

摘要

An air cooled turbine airfoil with an impingement plate bonded over multiple impingement cooling surfaces of the airfoil, where the impingement plate forms a series of double or triple impingement cooling for separate surfaces of the airfoil. The impingement plate can be shaped and sized to fit over an airfoil surface that requires multiple impingement cooling.

主权项

1. An air cooled turbine airfoil comprising:
an airfoil having a leading edge region, a trailing edge region, a pressure side wall, and a suction side wall; a first impingement surface and a second impingement surface of the airfoil separated by a rib; an inner plate bonded over the first impingement surface and the second impingement surface; the inner plate having an arrangement of first impingement cooling holes over the first impingement surface and second impingement cooling holes over the second impingement surface; the inner plate having an arrangement of return air holes in a section over the first impingement surface; an outer plate bonded over the inner plate to form a first impingement cooling chamber separated from a second impingement cooling chamber; and, the outer plate having an arrangement of cooling air supply holes and standoffs extending from a bottom side and aligned with the first impingement cooling holes to form a closed cooling air passage; wherein, cooling air from an external source flows through the cooling air supply holes in the outer plate and through the standoffs and the first impingement cooling air holes to provide impingement cooling to the first impingement surface, flows through the return air holes, and then through the second impingement cooling holes to provide impingement cooling to the second impingement surface.