Principles for Aircraft Exergy Mapping

  • Frederick Berg

Student thesis: Doctoral ThesisPhD


An increasing emphasis on energy eciency in aircraft systems has in recentyears led to greater interest in integrated design and optimisation withinthe industry. New tools are needed to understand, compare and manage energyuse of an aircraft throughout its design and operation. This thesis describes a new methodology to meet this need: aircraft exergy mapping.The choice of exergy, a 2nd law metric, to describe the energy ows is fundamental to the methodology, providing numerous advantages over energy alone.The basis for time-variant exergy analysis, a necessity when analysing aircraft systems in detail, is established. A set of software tools were developed to enable the creation, storage and analysis of the exergy map data.To study the ecacy of the method for analysing a time-variant system, ahydraulic wave power test rig was used as a case study. The system was equipped with sensors to provide pressure and ow readings at relevant locations. A model of the system was used to supplement the exergy map detail.Since aircraft will experience a range of atmospheric conditions during a ight,the eects of this on exergy calculations must be considered. A turbojet simulationwas used to show that a reference state other than the varying, immediatelyexterior atmospheric conditions leads to unacceptable inaccuracy.To consider the process of exergy mapping a whole aircraft, a case study basedon an Airbus A320 was created, including a performance and turbofan model.An air conditioning system model represented a lower energy subsystem. Furtheranalysis of the exergy map included the establishment of a method for assigningmass-induced exergy destruction and the attribution of costs to the aircraft casestudy. A comparison between two exergy maps of the same aircraft over dierentmissions is made.
Date of Award31 Dec 2013
Original languageEnglish
Awarding Institution
  • University of Bath
SupervisorPatrick Keogh (Supervisor) & Martin Balchin (Supervisor)

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