Advanced Exergy Analysis of an Air Craft Gas Turbine Engine at Different Power Loading Operations

The innovations in aircraft propulsion have been identified as the key parameter towards the progress in transportation. Continuous advancement in the performance and efficiency of propulsion has enabled aircraft to travel over larger distances with higher speed. Aviation is also responsible for approximately 2% of total greenhouse gas emission and is expected to grow around 3% by 2050. The present article aims to use the exergetic analysis of a turboprop engine which should be helpful in designing of such engines and also helps these engine users to regulate and select the operation modes. A gas turbine with film air cooling of turbine blades has been proposed to be the turboprop engine. The engine is analyzed on exergy point of view at different power loading operation modes and the performance is studied. Selected exergetic measures under consideration are Exergy Efficiency, Fuel Exergy Depletion Ratio, Relative Exergy Consumption Ratio, Exergetic Improvement potential and Productivity Lack ratio. The total fuel exergy depletion ratio of the turboprop engine is estimated to be around 64.7 % at 100% loading. Also, among the identified cycle components, combustion chamber is identified as the main source (~ 35%) of the exergy destruction and, thus is the biggest contributor to the overall irreversibility of the system. The exergy efficiency is observed to be minimum at 75 % mode and maximum for Take-off. The exergetic improvement potential of the thermodynamic inefficiencies increases with increase in fuel-air ratio from 75%-mode to Take-off mode. The combustor section of the engine has been identified as the greatest source of relative exergy consumption ratio (63 %) and productivity lack ratio (51 %) followed by the turbine and compressor sections (at take off mode).