High temperature turbine nozzle for temperature reduction by optical reflection and process for manufacturing

Abstract

A high temperature gas turbine component for use in the gas flow path that also is a specular optical reflector. A thin layer of a high temperature reflector is applied to the gas flow path of the component, that is, the surface of the component that forms a boundary for hot combustion gases. The component typically includes a thermal barrier coating overlying the high temperature metallic component that permits the component to operate at elevated temperatures. The thermal barrier coating must be polished in order to provide a surface that can suitably reflect the radiation into the gas flow path. A thin layer of the high temperature reflector the is applied over the polished thermal barrier coating by a process that can adequately adhere the reflector to the polished surface without increasing the roughness of the surface. The high temperature reflector can be applied to any surface aft of the compressor, such as on a turbine nozzle. The surface reflects radiation back into the hot gas flow path. The reflected radiation is not focused onto any other hardware component. The design of the component is such that the radiation is returned to the gas flow path rather than absorbed into a component wall that only serves to increase the temperature of the wall.