SUSTAINABLE ASSESSMENT OF TURBOFAN ENGINE INTEGRATED WITH ORGANIC RANKINE CYCLE THROUGH EXERGETIC APPROACH

Abstract

The growth in civil aviation industry causes an unavoidable increase in greenhouse gas emission and the need to achieve a system with good performance and also sustainable. One of the proposed solutions is to use energy and exergy analysis to calculate the performance and sustainability index of an engine. In this paper, an Organic Rankine Cycle (ORC) is connected to a two-spools turbofan engine with mixed exhaust flow in order to extract the waste heat from the engine’s exhaust. The objective is to perform sustainable analysis based on exergy and to assess the impact of recovering waste heat using ORC to overall index of sustainability. The parameters used for ORC system are provided by Engineering Equation Solver (EES) and this data is then used to determine the exergetic sustainability index of the turbofan engine integrated with ORC system. The turbofan engine data is taken from the simulation results by using GasTurb13 software. In order to assess the sustainability of the whole system, the overall exergy efficiency, waste exergy ratio, exergy destruction factor, environmental effect factor and the exergetic sustainability index are determined. The results obtained for these parameters are 63%, 86%, 17%, 1.37 and 0.73 respectively. Finally the result is compared to the actual turbofan engine without ORC system in order to evaluate the impact of integrating the ORC to the engine and the conclusion found is that a turbofan engine with ORC system results in a higher sustainability index compared to the one without the ORC.