This master thesis deals with the understanding of the secondary air system of athree spool turbofan. The main purpose is the creation of secondary air systemand thermal models to evaluate the behavior of this kind of engine architectureand estimate the pros and cons in comparison with a typical two spool turbofan. Afinite element model of the secondary air system of the engine has been designedbased on the experience of typical jet engines manufactured by Snecma. Theinner thermodynamic pattern and mass flow rates of the engine were obtained.Some local improvements were then made by making analogies with the enginesmanufactured by Snecma. After having communicated the results to theperformance unit to get updates thermodynamic cycles, a quite reliable model wasobtained and can be used as a reference for further studies of this kind of engineat Snecma.

This master thesis deals with the understanding of the secondary air system of athree spool turbofan. The main purpose is the creation of secondary air systemand thermal models to evaluate the behavior of this kind of engine architectureand estimate the pros and cons in comparison with a typical two spool turbofan. Afinite element model of the secondary air system of the engine has been designedbased on the experience of typical jet engines manufactured by Snecma. Theinner thermodynamic pattern and mass flow rates of the engine were obtained.Some local improvements were then made by making analogies with the enginesmanufactured by Snecma. After having communicated the results to theperformance unit to get updates thermodynamic cycles, a quite reliable model wasobtained and