ON OPTIMUM WEDGES AND SEMICONES IN HYPERSONIC VISCOUS FLOW,

Abstract

The class of wedges and semicones whose upper surfaces are parallel to the undisturbed flow is considered and, with reference to the range where viscous interaction can be neglected, the effect of the thickness ratio on the lift-to-drag ratio is investigated under the hypotheses that (1) the pressure distribution is that of the hypersonic, small-disturbance theory and (2) the local shear stress is proportional to the square root of the static pressure at the outer edge of the boundary layer, assumed laminar. A solution is derived for the optimum thickness ration parameter and the maximum lift-to-drag ratio parameter as functions of the similarity parameter. This solution is then compared with the approximate solution obtained by assuming a modified Newtonian pressure coefficient and an average skin-friction coefficient which is independent of the shape during the optimization process. It is found that the latter solution is a good approximation to the former, since the predicted lift-to-drag ratios are within 2.5%(wedge) and 1.4%(semicone)of the maximum values.

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1967
Accession Number
AD0804912

Entities

People

  • Angelo Miele
  • Arthur H. Lusty Jr

Organizations

  • Rice University

Tags

DTIC Thesaurus Topics

  • Boundary Layer
  • Coefficients
  • Drag
  • Flow
  • Friction
  • Pressure Distribution
  • Shear Stresses
  • Skin Friction
  • Square Roots
  • Static Pressure
  • Thickness
  • Viscous Flow

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Fluid Dynamics.

Technology Areas

  • Hypersonics