Exhaust Plume Temperature Effects on Nozzle Afterbody Performance over the Transonic Mach Number Range

Abstract

Results of an experimental and analytical research investigation on nozzle/afterbody drag are presented. Experimental afterbody (and boattail) drag coefficients and pressure distributions are discussed for an isolated, strut- mounted nozzle/afterbody model for the Mach number range from 0.6 to 1.5. Some data are also given for free-stream unit Reynolds numbers from one million to approximately four million per foot. The experimental data were obtained for the basic model with an air-cooled and a water-cooled Ethylene/air combustor to provide hot-jet duplication as well as cold-jet simulation. The temperature of the nozzle exhaust gas was varied from 530R (burner-off) to approximately 2500R for several nozzle pressure ratios from jet-off to those corresponding to a moderately under-expanded exhaust plum. The initial series of experiments was conducted with the air-cooled combustors, and the effect of jet temperature on afterbody drag was somewhat masked by the effects of the secondary airflow from the cooling air. The general trend, however, shows a decreasing afterbody drag with increasing exhaust gas temperature and with decreasing secondary airflow at a fixed nozzle pressure ratio.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1974
Accession Number
AD0781377

Entities

People

  • C. E. Robinson
  • M. D. High

Organizations

  • Arnold Engineering Development Complex

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Air Cooled
  • Boundary Layer
  • Combustion
  • Combustion Chambers
  • Combustors
  • Computational Fluid Dynamics
  • Computational Science
  • Exhaust Gases
  • Exhaust Plumes
  • Fluid Dynamics
  • Mach Number
  • Pressure Distribution
  • Pressure Measurement
  • Reynolds Number
  • Secondary Flow
  • Turbofan Engines
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Combustion and Flow Dynamics.