A combustor research and development program is proposed to provide a basic design for a prototype combustor that can be used in a semi-closed Brayton cycle that features recirculation of the exhaust gases. Recirculating regenerative engines require an innovative burner concept to operate with large quantities of diluent which reduces the oxygen concentration as well as the availability of secondary combustion air that reperesents a departure from conventional burner designs. The proposed program will build upon the successful Phase I effort and complement an on-going program sponsored by NASA Lewis Research Center to demonstrate regenerative feedback flow concepts using semi-closed cycles. The Phase II effort will be performed by the Team of UNISTRY Associates (diagnostics), Allison Engine Company (combuster design), Alturdyne (fabrication), and the University of Florida (testing). The combuster will be designed to provide twice the recirculation of the NASA feedback flow demonstration project. The emphasis of the Phase II investigation will be on combustor design and combustor diagnostics which can be used for future design tools. Testing will be done at the University of Florida using a ROVER gas turbine recirculating system (built during Phase I) that will be reconfigured into a semi-closed cycle with in-line high pressure recouperator and cooler in the closed loop of the cycle. This will provide operational data for this class of engines in addition to accomplishing the primary combuster-design objectives.
Benefits: The design of a combustor featuring exhaust gas recirculation has the potential for significantly improving and controlling environmental contaminating pollutants. Moreover, when used in a regenerative semi-closed cycle turbine engine, an improvment in performance, economy, and weight to power ratio can be achieved.
