A Velocity-Correction Formula for the Calculation of Transonic Mach Number Distributions Over Diamond-Shaped Airfoils

Abstract

A velocity-correction formula is proposed for the purpose of calculating, from the known Mach number distribution for a diamond-shaped airfoil at a stream Mach number of 1.0, Mach number distributions on the same airfoil at speeds from a Mach number of about 0.8 to shock-attachment Mach number. The time required to calculate these additional Mach number distributions is small in comparison with the time required by rigorous methods. The accuracy of the results for stream Mach numbers near 1.0 is of the same order as the accuracy of the known Mach number distribution. Moreover, the results tend to become exact as the stream Mach number is increased toward that for shock attachment. An expression for the rate of change of local Mach number with stream Mach number is derived and an explicit equation for the drag coefficient as a function of stream Mach number and thickness ratio is given.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1951
Accession Number
ADA380375

Entities

People

  • H. R. Ivey
  • Keith C. Harder

Organizations

  • National Aeronautics and Space Administration

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Aeronautical Laboratories
  • Attachment
  • Boundary Layer
  • Cartesian Coordinates
  • Coefficients
  • Compression Waves
  • Computational Fluid Dynamics
  • Differential Equations
  • Distribution Curves
  • Equations
  • Flow
  • Free Stream
  • Mach Number
  • Pressure Distribution
  • Shock Waves
  • Waves

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Fluid Dynamics.