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Effect of Bypass Ratio on Optimal Fan Outer Pressure Ratio and Performance for Turbofan Engines

  • Rui XueEmail author
  • Jun Jiang
  • Anthony Jackson
Original Paper
  • 4 Downloads

Abstract

This study was carried out to explore the effect of bypass ratio on optimal fan outer pressure ratio and the performance of turbofan engine with the same engine core. The member of Rolls-Royce Trent family, Trent-XWB, is chosen as the baseline engine. Based on the published data, a model for the simulation of engine performance was set up. Then, a series of engine models with different bypass ratios were established based on the same Trent-XWB engine core and the way to get optimal fan outer pressure ratio was derived. It was concluded that for the fixed engine core, when the bypass ratio was chosen, there would be one optimal outer pressure ratio existing which could make the thrust maximum and the specific fuel consumption reach minimum. By comparing the performance of the turbofan engines with different bypass ratios, it shows that the increase of bypass ratio results in higher thrust and lower specific fuel consumption. However, the additional cost like the increase of both drag and weight needs to be taken into account at the preliminary design stage in practice.

Keywords

Bypass ratio study Optimal fan outer pressure ratio Engine performance 

Nomenclature

BPR

Bypass ratio

COT

Combustor outlet temperature

FIPR

Fan inner pressure ratio

FOPR

Fan outer pressure ratio

HPCPR

High pressure compressor pressure ratio

IPCPR

Intermediate pressure compressor pressure ratio

IPC

Intermediate pressure compressor

ISA

International standard atmosphere

LP

Low pressure

OPR

Overall pressure ratio

PR

Pressure ratio

SFC

Specific fuel consumption

SLS

Sea level static

W

Air mass flow rate

Notes

Funding

This work has been supported by the National Natural Science Foundation of China (Grant No. 51706170) and China Postdoctoral Science Foundation (Grant no. 2017M623185).

Compliance with ethical standards

Conflict of interest

The authors declare that there is no conflict of interest.

References

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Copyright information

© The Korean Society for Aeronautical & Space Sciences 2019

Authors and Affiliations

  1. 1.State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Laboratory for Vibration Control of Aerospace StructuresSchool of Aerospace, Xi’an Jiaotong UniversityXi’anPeople’s Republic of China
  2. 2.AECC Xi’an Aero-Engine Control CompanyXi’anPeople’s Republic of China
  3. 3.Centre for Propulsion EngineeringCranfield UniversityBedfordshireUK

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