Performances Analysis of High By Bass Jet Engine With Intercooling and Regeneration

The recovery of heat available in the exhaust of a gas turbine engine is one of the main challenge for the aircraft propulsion systems engineers. In fact this can have great impact on fuel saving and, consequently, environment protection. Infact with an efficient recovery of the heat present in the exhaust of jet engines it is possible to rise their thermal efficiency. The practice used to achieve this goal is regeneration. It consists in recovering part of the enthalpy present in exhaust gas to pre heat air before introducing it into the combustion chamber. This practice is well known and widely used in ground power plants. It is not utilized in aircraft engines mainly for the extra weight and size due to the presence of the heat exchangers and for the more complicated flow pattern that it comes from it The efficiency of regeneration is improved if it is used at the same time with intercooling, a practice consisting in cooling the air during the compression process so to reduce the compression work. In this work a thermodynamic cycle analysis is performed to put in evidence the advantages, in terms of power increase and fuel consumption reduction, of the introduction of regeneration and intercooling in a turbofan engine at high by-pass ratio