Heat Transfer in Incompressible Laminar External Boundary Layers: Similarity Solutions

New solutions are presented for non-stationary boundary layers induced by planar, cylindrical and spherical Chapman-Jouguet (C-J) detonation waves. The numerical results show that the Prandtl number ( Pr ) has a very significant influence on the boundary-layer-flow structure. A comparison with available time-dependent heat-transfer measurements in a planar geometry in a 2H 2 + O 2 mixture shows much better agreement with the present analysis than has been obtained previously by others. This lends confidence to the new results on boundary layers induced by cylindrical and spherical detonation waves. Only the spherical-flow analysis is given here in detail for brevity.

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Closure to “Discussion of ‘Analysis of Heat Transfer Regulation and Modification Employing Intermittently Emplaced Porous Cavities’ and ‘Analysis of Flow and Heat Transfer Over an External Boundary Covered With a Porous Substrate’” (1995, ASME J. Heat Transfer, 117, p. 554)

Journal of Heat Transfer ◽

10.1115/1.2822568 ◽

1995 ◽

Vol 117 (2) ◽

pp. 554-555 ◽

Cited By ~ 2

Author(s):

K. Vafai ◽

S. J. Kim

Keyword(s):

Heat Transfer ◽

External Boundary ◽

Porous Substrate ◽

Flow And Heat Transfer

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Forced convective heat transfer through boundary layers in non-Newtonian fluids.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.51.2006 ◽

1985 ◽

Vol 51 (466) ◽

pp. 2006-2014

Author(s):

Akira NAKAYAMA ◽

A.V. SHENOY ◽

Hitoshi KOYAMA

Keyword(s):

Heat Transfer ◽

Convective Heat Transfer ◽

Boundary Layers ◽

Convective Heat ◽

Newtonian Fluids ◽

Forced Convective Heat Transfer

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Effects of Embedded Vortices on Film-Cooled Turbulent Boundary Layers

Journal of Turbomachinery ◽

10.1115/1.3262239 ◽

1989 ◽

Vol 111 (1) ◽

pp. 71-77 ◽

Cited By ~ 10

Author(s):

P. M. Ligrani ◽

A. Ortiz ◽

S. L. Joseph ◽

D. L. Evans

Keyword(s):

Heat Transfer ◽

Boundary Layers ◽

Film Cooling ◽

Free Stream ◽

Flow Behavior ◽

Local Heat Transfer ◽

Local Heat ◽

Turbulent Boundary Layers ◽

Stream Velocity ◽

Longitudinal Vortices

Heat transfer effects of longitudinal vortices embedded within film-cooled turbulent boundary layers on a flat plate were examined for free-stream velocities of 10 m/s and 15 m/s. A single row of film-cooling holes was employed with blowing ratios ranging from 0.47 to 0.98. Moderate-strength vortices were used with circulating-to-free stream velocity ratios of −0.95 to −1.10 cm. Spatially resolved heat transfer measurements from a constant heat flux surface show that film coolant is greatly disturbed and that local Stanton numbers are altered significantly by embedded longitudinal vortices. Near the downwash side of the vortex, heat transfer is augmented, vortex effects dominate flow behavior, and the protection from film cooling is minimized. Near the upwash side of the vortex, coolant is pushed to the side of the vortex, locally increasing the protection provided by film cooling. In addition, local heat transfer distributions change significantly as the spanwise location of the vortex is changed relative to film-cooling hole locations.

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