Heat Transfer and Laminar Boundary-Layer Distributions in an Internal Subsonic Gas Stream at Temperatures Up to 13,900 Deg R

Abstract

Radial distributions of velocity, enthalpy, and mass flux have been evaluated experimentally in a laminar boundary layer from calorimetric probe measurements obtained in a subsonic flow of arc-heated argon in the entrance region of an axisymmetric constant-diameter duct. Longitudinal distributions of heat flux were also determined. Because of the large free stream to wall temperature ratios the boundary-layer mass flux exceeded that of the free stream sufficiently to produce negative values of the displacement thickness. The longitudinal distributions of the heat transfer and the radial distributions of the enthalpy difference and the velocity were found to agree reasonably well with laminar boundary-layer predictions which account for large variations in properties.