The Research On Optimization Method Of Aircraft Environmental Control System

At present, with the rapid development of aviation, commercial aircraft and fighter need much better Environmental control systems.In order to satisfy the aircraft performance requirements, the aircraft environmental control systems also have been improved and optimized.Bleed air driven ECS developed to be pressor system from simple system, and there are three-wheel system (T-C-F) and four-wheel system (T-T-C-F) instead of the two-wheel system (T-C or T-F). With All Electric ECS application in the Boeing B787, so there is another type of ECS. All Electric ECS does not need bleed air from engines to driven, it compresses ram air with its own means of compression: two Electric compressors.Therefore the All Electric ECS can make engines with better performance. But the additional and different components adopted for the All Electric ECS generate an overall weight increase of the system. And it brings adverse effects to the aircraft. To compare different environmental control systems'performance, we select three-wheel system, four-wheel system and All Electric ECS as objects, and adopt the entropy increase method and exergy loss method to analyse them. Then we calculate the fuel mass penalties of these systems and estimate the performance of these systems comprehensively.In order to get applicable environmental control systems for different ranges and different capacities of commercial aircraft, we analyse the influence of the range and capacity on the ECS's fuel mass penalties.In order to reduce the exergy loss of environmental control system, we choose exergy loss as objective function, and analyse the influence of the parameters of each part on the exergy loss of the system.And conclude the method to reduce the exergy loss of each system.We take the exergy loss as objective function, given the range and capacity of the commercial aircraft, and select the entire flight for the analysis phase.We calculate the overall exergy loss of four-wheel system and All Electric ECS.It is concluded that the All Electric ECS has less exergy loss throughout the flight.