Experimental Investigation of High Performance, Short, Thrust Augmenting Ejectors

Abstract

Results of an experimental investigation concerning the design and testing of air-to-air thrust augmenting ejectors utilizing short curved-wall diffusers are presented. These ejectors were designed primarily according to the procedure established in an analytical research effort sponsored by DTNSRDC from 1980-1981. Two of the three ejectors tested have identical mixing chambers. The mixing chamber inlet area to the primary nozzle area ratio lambda was 40. The overall ejector length-to-mixing chamber diameter ratios L/D(overall) were 6.09 and 6.16; diffuser area ratios AR(diff) were 1.33 and 1.46, respectively. The third ejector had an L/D(overall) of 6.02, a lambda of 20 and an AR(diff) of 1. 26. The best observed thrust augmentation ratio phi and the modified thrust augmentation ratio phi sub 2 were 2.11 and 1.91 respectively for a sonic primary jet. The modified thrust augmentation ratio phi sub 2 accounts for the penalty of suction in preventing flow separation in the diffuser. These levels of thrust ratio were derived from velocity measurements at the ejector exit. Independent thrust measurements obtained with strain gages on the mixing chamber agree with the force calculated from the momentum data. The experimentally observed ejector performance data correlated well with the predicted values. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1983
Accession Number
ADA125529

Entities

People

  • Francois Ntone
  • Jiang Tong
  • Tah-teh Yang

Organizations

  • Clemson University

Tags

Communities of Interest

  • Air Platforms
  • Materials and Manufacturing Processes
  • Sensors

DTIC Thesaurus Topics

  • Boundary Layer
  • Boundary Layer Control
  • Data Reduction
  • Flow Rate
  • Flow Separation
  • Gages
  • Mass Flow
  • Measurement
  • Mechanical Engineering
  • Performance Tests
  • Pressure Distribution
  • Pressure Measurement
  • Propulsion Systems
  • Secondary Flow
  • Short Takeoff Aircraft
  • Strain Gages
  • Test Facilities

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Marine Propulsion Engineering and Naval Architecture
  • Rocket Propulsion.