Design and Analysis of an Intercooled Turbofan Engine

The performance of an intercooled turbofan engine is analyzed by multidisciplinary optimization. A model for making preliminary simplified analysis of the mechanical design of the engine is coupled to an aircraft model and an engine performance model. A conventional turbofan engine with technology representative for a year 2013 entry of service is compared with a corresponding intercooled engine. A mission fuel burn reduction of 3.4% is observed. The results are analyzed in terms of the relevant constraints such as compressor exit temperature, turbine entry temperature, turbine rotor blade temperature, and compressor exit blade height. It is shown that the gas path of an intercooled engine for medium range commercial transport applications, having an overall pressure ratio greater than 70 in top of climb, may still be optimized to fulfill a compressor exit blade height constraint. This indicates that a state of the art high pressure compressor efficiency can be achieved. Empirical data and a parametric computational fluid dynamics (CFD) study are used to verify the intercooler heat transfer and pressure loss characteristics.