Estimation of Critical Speeds of Airfoils and Streamline Bodies

Abstract

Methods and charts are presented for estimating the critical compressibility speeds of a large number of airfoils and streamline bodies. A method introduced to allow for the combination of these parts permits the estimation of the critical speed of an airplane wing including the effects of fuselage and nacelles. The systematic effects of thickness, thickness distribution, camber, camber location, leading-edge radius, and lift coefficient are considered. The results indicate that with a given lift coefficient the thickness of the airfoil or of the body is the primary factor controlling its critical speed. For high values of critical speed, the location of maximum thickness and maximum camber should be near the 50-percent-chord point. An airfoil should be designed to have a high value of the critical speed for the lift coefficient at which high-speed operation will occur.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1940
Accession Number
ADB807282

Entities

People

  • R. G. Robinson
  • Ray H. Wright

Organizations

  • National Advisory Committee for Aeronautics

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aircrafts
  • Airfoils
  • Airplanes
  • Bodies
  • Compressible Flow
  • Compressive Properties
  • Fineness Ratio
  • Flow
  • Fuselages
  • Geometry
  • Leading Edges
  • Mach Number
  • Pressure Distribution
  • Pressure Gradients
  • Shock Waves
  • Thickness
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Aerodynamics.