INVESTIGATION OF PERFORMANCE OF MULTIPLE GAS GENERATORS WITH A COMMON EXHAUST

Abstract

A system wherein multiple engines exhaust into a common exhaust is analyzed on both a steady-state performance and transient response basis. A failure analysis of the system is also included. Engine to engine variations have been considered together with the effects of externally induced mismatches. It is concluded that maximum power is obtained by rating the engines on a T5 basis and trimming the exhaust area upon installation. It is shown that the greater the number of engines combined in a common exhaust, the lower the average performance compared to separately ducted engines; however, the averaging effect of the number of engines and the trim method recommended keeps the minimum system performance above that which would be calculated from single- engine guarantee performance. A fundamental problem in the common engine system is that of acceleration delay or hangup resulting in deceleration during transient conditions. This problem can be eliminated in the two-engine system by using a high idle speed and can be prevented in the four-engine system by a combination of high idle speed and can be prevented in the four-engine system by a combination of high idle speed and a simple gas generator coordination control. If accessory power is to be extracted, this must be extracted equally from all engines.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1966
Accession Number
AD0635950

Entities

People

  • Roger M. Woodward

Organizations

  • General Electric

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Abstracts
  • Aircrafts
  • Airframes
  • Analog Computers
  • Back Pressure
  • Compressors
  • Computer Programs
  • Contracts
  • Control Systems
  • Digital Computers
  • Exhaust Nozzles
  • Exhaust Systems
  • Lift Fans
  • Mass Flow
  • Power Levels
  • Propulsion Systems
  • Test And Evaluation

Readers

  • Aerospace Engineering
  • Mathematics or Statistics