초록 ▼

An apparatus and method are provided for minimizing differential thermal expansion in external cooling air structures formed on the shrouds of the vane segments of a gas turbine. The external cooling air structure is formed from a laminate comprised of two layers joined in sandwich-like fashion. A p

An apparatus and method are provided for minimizing differential thermal expansion in external cooling air structures formed on the shrouds of the vane segments of a gas turbine. The external cooling air structure is formed from a laminate comprised of two layers joined in sandwich-like fashion. A passageway, which may be of a serpentine arrangement, is formed between the two layers of the laminate. Hot gas flowing over the shroud is directed through the passageway, thereby heating the structure so that its temperature is close to that of the shroud. Cooling air is bled into the hot gas directed to the passageway so as to reduce the temperature of the hot gas flowing through the passageway and prevent overheating of the external cooling air structure.

대표청구항 ▼

A gas turbine comprising: (a) a combustion section having means for producing a hot gas; (b) a turbine section having a plurality of shrouds disposed therein, each of said shrouds having first and second surfaces, said turbine section having means for directing said hot gas to flow over each of said

A gas turbine comprising: (a) a combustion section having means for producing a hot gas; (b) a turbine section having a plurality of shrouds disposed therein, each of said shrouds having first and second surfaces, said turbine section having means for directing said hot gas to flow over each of said first surfaces; (c) a supply of cooling air; d) a structure affixed to said second surface of each of said shrouds, each of said structures having first and second layers, each of said first and second layers having first and second surfaces, said first and second layers joined along their respective first surfaces, a first passageway formed between each of said first and second layers, each of said first passageways having a serpentine arrangement and an inlet and an outlet, each of said inlets and outlets in flow communication with said hot gas flowing over said first surfaces of said shrouds, said second surface of said first layer forming a second passageway through which said cooling air flows; and e) means for inducing a portion of said hot gas flowing over said first surfaces of each of said shrouds to flow through each of said first passageways. In a gas turbine through which a hot gas flows, having a vane segment, said vane segment having a shroud, said shroud having first and second surfaces, said hot gas flowing over said first surface, cooling air being supplied to said shroud, said vane segment having a laminate structure affixed to said second surface of said shroud, said laminate structure forming a first passageway for said cooling air on said second surface of said shroud, a second passageway formed in said laminate structure, a method of reducing thermal expansion between said structure and said shroud comprising the steps of: a) directing a first portion of said hot gas flowing over said first surface of said shroud to said second passageway; b) flowing said first portion of said hot gas through said second passageway; c) returning said hot gas flowing through said second passageway to said hot gas flowing over said first surface of said shroud.