A Method for Determining Drag Coefficients from Observed Position Data.

Abstract

A method is presented for computing the aerodynamic drag of a body in free flight. Polynomial least squares smoothing of position data is used for the first estimate with an optional provision of improving these results by matching arc length. All values thus obtained from one or more drops are then used to obtain a single least squares fit with the drag coefficient formula of T. S. Walton and Daniel Shanks. The nonlinear portions of this fitting problem are solved with good results using a quadratic minimization routine provided the data cover a sufficient Mach number range. This method is both fast and accurate. It replaces a procedure which was more expensive in computer time and in the required efforts of experienced personnel. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1970
Accession Number
AD0869666

Entities

People

  • C. H. Frick
  • L. J. Mcanelly
  • R. G. Barker

Organizations

  • Naval Surface Warfare Center Dahlgren Division

Tags

DTIC Thesaurus Topics

  • Aerodynamic Drag
  • Coefficients
  • Computers
  • Drag
  • Flight
  • Free Flight
  • Mach Number
  • Physical Properties
  • Polynomials

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Computational Modeling and Simulation
  • Linear Algebra