Principles for Aircraft Energy Mapping

Doctoral thesis English RESTRICTED
Berg, Frederick T N (2013)

An increasing emphasis on energy eciency in aircraft systems has in recent<br/>years led to greater interest in integrated design and optimisation within<br/>the industry. New tools are needed to understand, compare and manage energy<br/>use of an aircraft throughout its design and operation. This thesis describes a new methodology to meet this need: aircraft exergy mapping.<br/>The choice of exergy, a 2nd law metric, to describe the energy ows is fundamental to the methodology, providing numerous advantages over energy alone.<br/>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.<br/>To study the ecacy of the method for analysing a time-variant system, a<br/>hydraulic 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.<br/>Since aircraft will experience a range of atmospheric conditions during a ight,<br/>the eects of this on exergy calculations must be considered. A turbojet simulation<br/>was used to show that a reference state other than the varying, immediately<br/>exterior atmospheric conditions leads to unacceptable inaccuracy.<br/>To consider the process of exergy mapping a whole aircraft, a case study based<br/>on an Airbus A320 was created, including a performance and turbofan model.<br/>An air conditioning system model represented a lower energy subsystem. Further<br/>analysis of the exergy map included the establishment of a method for assigning<br/>mass-induced exergy destruction and the attribution of costs to the aircraft case<br/>study. A comparison between two exergy maps of the same aircraft over dierent<br/>missions is made.
Share - Bookmark