Patent ID: 7870739

Claim:
A gas turbine engine comprising: a. an air compressor; b. a plurality of combustion chambers, each comprising an intake end and an outlet end, and connected in parallel with respect to airflow; c. a plurality of transitions, each comprising an inboard side, two lateral sides, and an outboard side, and each associated with a respective combustion chamber, providing fluid communication between the respective outlet end and an entrance port of a turbine; d. a curved diffuser in fluid communication between the compressor and a plenum surrounding the transitions, comprising an inboard wall and an outboard wall defining an annular passage for air therebetween, the inboard wall and outboard wall together being effective to direct a primary portion of total airflow from the compressor to the intake ends, additionally comprising a plurality of spaced apart ports disposed along the inboard wall for passage of a secondary portion of the total airflow; and e. at least one pressure boundary element directing the secondary portion through at least one array of apertures on said at least one pressure boundary element, the respective apertures of sizes and spacing effective to provide a desired degree of impingement cooling to the at least one transition, wherein the inboard wall and the pressure boundary element define a confined space through which a secondary portion of the total airflow flows between the port and the apertures for said impingement cooling.