HEAT TRANSFER AND BOUNDARY-LAYER TRANSITION ON A HIGHLY POLISHED HEMISPHERE-CONE IN FREE FLIGHT AT MACH NUMBERS UP TO 3.14 AND REYNOLDS NUMBERS UP TO 24 X 106

Abstract

A highly polished hemisphere-cone having a ratio of nose radius to base radius of 0.74 and a halfangle of 14.5 degrees was flight tested at Mach numbers p to 4.70. Temperature and pressure data were obtained at Mach numbers up to 3.14 and a free-stream Reynolds number of 24 x 10 to the 6th power based measured an interferometer. The measured Stanton numbers were in good agreement with theory. Transition Reynolds numbers based on the laminar boundary-layer momentum thickness at transition ranged from 2,190 to 794. Comparison with results from previous tests of blunt shapes having a surface roughness of 20 to 40 microinches showed that the high degree of polish was instrumental in delaying the transiton body diameter. The nose of the model had a surface roughness of 2 to 5 microinches as measured an interferometer. The measured Stanton numbers were in good agreement with theory. Transition Reynolds numbers based on the laminar boundary-layer momentum thickness at transition ranged from 2,190 to 794. Comparison with results from previous tests of blunt shapes having a surface roughness of 20 to 40 microinches showed that the high degree of polish was instrumental in delaying the transition from laminar to turbulent flow. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1961
Accession Number
AD0263080

Entities

People

  • James J. Buglia

Organizations

  • National Aeronautics and Space Administration

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Boundary Layer Transition
  • Free Flight
  • Free Stream
  • Heat Transfer
  • Laminar Boundary Layer
  • Layers
  • Mach Number
  • Reynolds Number
  • Roughness
  • Surface Roughness
  • Transitions
  • Turbulent Flow

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.