The Design & Analysis of a Mixed Exhaust Turbofan Engine with Intercooling and Regeneration

In this paper, the thermodynamic cycle of a real, mixed exhaust turbofan engine with intercooling and regeneration was analyzed for key output characteristics of specific thrust, specific fuel consumption, and overall efficiency. An intercooler was implemented between the low-pressure and high-pressure compressors. The intercooler heat exchanger was designed to be connected to the fan duct, where the cold fan duct air was used to reduce temperatures in the core duct. A regenerative heat exchanger was implemented downstream of the turbine outlet to capture exhaust heat. A fraction of the high pressure compressor outlet flow was heated in the regenerator and then fed into the combustion chamber. The flow was then mixed with fan duct flow and proceeds to the afterburner. As a baseline design, a low-bypass ratio, normal mixed exhaust turbofan engine is analyzed. Results show that when operating a Mixed Exhaust Turbofan Engine with Regeneration and Intercooling (MEXTRI) cycle without afterburning at an overall compression ratio between 20-30, there was a reduction in specific fuel consumption and increase in overall efficiency, while having a slight penalty in specific thrust.