Heat Transfer During Wind Flow over Rectangular Bodies in the Natural Environment

1981 ◽  
Vol 103 (2) ◽  
pp. 262-267 ◽  
Author(s):  
F. L. Test ◽  
R. C. Lessmann ◽  
A. Johary
Keyword(s):  
Heat Transfer ◽  
Experimental Investigation ◽  
Wind Flow ◽  
Finite Width ◽  
Two Dimensional ◽  
Disturbance Intensity ◽  
Temperature Heat ◽  
Two Dimensional Flow ◽  
Transfer Behavior ◽  
Made In

An experimental investigation has been performed to determine the constant temperature heat transfer behavior on the upper surface of a rectangular plate with a chord length of 122 cm (48 in.), a width of 81.3 cm (32 in.) and a thickness aspect ratio of 6/1. Special side attachments were made in order to maintain approximately two-dimensional flow over the finite width body when exposed to varying wind directions. The angle of attack was 40 deg or greater. Quasi-local values of STRe were found to be 200 percent higher than wind tunnel values and 300 percent higher than analytical predictions. The disturbance intensity of the wind flow was in the range of 20 to 50 percent and is thought to be related to the increase in heat transfer since the flow over the plate was found to be laminar.

An Experimental Study of Heat Transfer During Forced Convection over a Rectangular Body

1980 ◽  
Vol 102 (1) ◽  
pp. 146-151 ◽  
Author(s):  
F. L. Test ◽  
R. C. Lessmann
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Experimental Investigation ◽  
Aspect Ratio ◽  
Surface Temperature ◽  
Stagnation Point ◽  
Temperature Heat ◽  
Transfer Behavior ◽  
Rectangular Body ◽  
Rectangular Model

An experimental investigation has been performed to determine the constant surface temperature heat transfer behavior on the upper surface of a rectangular model with a chord length of 20.3 cm (8 in.) and an aspect ratio of 6/1. Data were obtained for angles of attack from 0 to 50 deg and freestream velocities of 9.1, 15.2, and 21.3 m/s (30, 50 and 70 ft/s). Separation existed on a portion of the upper surface for angles between 0 and 20 deg with the flow being turbulent after reattachment. Above 30 deg the flow was always laminar with the stagnation point on the upper surface. The heat transfer results in the laminar case were strongly influenced by freestream disturbances.

The response of a turbulent boundary layer to lateral divergence

1979 ◽  
Vol 94 (2) ◽  
pp. 243-268 ◽  
Author(s):  
A. J. Smits ◽  
J. A. Eaton ◽  
P. Bradshaw
Keyword(s):  
Boundary Layer ◽  
Circular Cylinder ◽  
Turbulent Boundary Layer ◽  
Structural Parameters ◽  
Axial Flow ◽  
Turbulence Structure ◽  
Two Dimensional ◽  
Transition Section ◽  
Two Dimensional Flow ◽  
Made In

Measurements have been made in the flow over an axisymmetric cylinder-flare body, in which the boundary layer developed in axial flow over a circular cylinder before diverging over a conical flare. The lateral divergence, and the concave curvature in the transition section between the cylinder and the flare, both tend to destabilize the turbulence. Well downstream of the transition section, the changes in turbulence structure are still significant and can be attributed to lateral divergence alone. The results confirm that lateral divergence alters the structural parameters in much the same way as longitudinal curvature, and can be allowed for by similar empirical formulae. The interaction between curvature and divergence effects in the transition section leads to qualitative differences between the behaviour of the present flow, in which the turbulence intensity is increased everywhere, and the results of Smits, Young & Bradshaw (1979) for a two-dimensional flow with the same curvature but no divergence, in which an unexpected collapse of the turbulence occurred downstream of the curved region.

A numerical model on transient, two-dimensional flow and heat transfer in He II

Cryogenics ◽  
1997 ◽  
Vol 37 (1) ◽  
pp. 1-9 ◽  
Author(s):  
T. Kitamura ◽  
K. Shiramizu ◽  
N. Fujimoto ◽  
Y.F. Rao ◽  
K. Fukuda
Keyword(s):  
Heat Transfer ◽  
Numerical Model ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Flow And Heat Transfer ◽  
Two Dimensional Flow

Heat Convection from a Horizontal Cylinder Rotating in a Quiescent Fluid

1986 ◽  
Vol 10 (3) ◽  
pp. 141-152
Author(s):  
H.M. Badr ◽  
S.M. Ahmed
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Mathematical Model ◽  
Horizontal Cylinder ◽  
Heat Transfer Process ◽  
Two Dimensional ◽  
Two Dimensional Flow ◽  
Boussinesq Fluid ◽  
The Mathematical Model ◽  
Quiescent Fluid

The aim of this work is a theoretical investigation to the problem of heat transfer from an isothermal horizontal cylinder rotating in a quiescent fluid. The study is based on the solution of the conservation equations of mass, momentum and energy for two-dimensional flow of a Boussinesq fluid. The effects of the parameters which influence the heat transfer process namely the Reynolds number and Grashof number are considered while the Prandtl number is held constant. Streamline and isotherm patterns are obtained from the mathematical model and the results are compared with previous experimental data. A satisfactory agreement was found.

Chaotic heat transfer in a periodic two-dimensional flow

1998 ◽  
Vol 10 (8) ◽  
pp. 2102-2104 ◽  
Author(s):  
E. Saatdjian ◽  
J. C. Leprevost
Keyword(s):  
Heat Transfer ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Two Dimensional Flow

Heat Transfer in the Separated and Reattached Flow on a Blunt Flat Plate

1974 ◽  
Vol 96 (4) ◽  
pp. 459-462 ◽  
Author(s):  
Terukazu Ota ◽  
Nobuhiko Kon
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Flat Plate ◽  
Leading Edge ◽  
Two Dimensional ◽  
Separated And Reattached Flow ◽  
The Heat Transfer Coefficient ◽  
Blunt Leading Edge ◽  
Made In

Heat transfer measurements are made in the separated, reattached, and redeveloped regions of the two-dimensional air flow on a flat plate with blunt leading edge. The flow reattachment occurs at about four plate thicknesses downstream from the leading edge and the heat transfer coefficient becomes maximum at that point and this is independent of the Reynolds number which ranged from 2720 to 17900 in this investigation. The heat transfer coefficient is found to increase sharply near the leading edge. The development of flow is shown through the measurements of the velocity and temperature in the separated, reattached, and redeveloped regions.

Base Heat Transfer in Two-Dimensional Subsonic Fully Separated Flows

1971 ◽  
Vol 93 (4) ◽  
pp. 342-348 ◽  
Author(s):  
John W. Mitchell
Keyword(s):  
Heat Transfer ◽  
Boundary Layer ◽  
Experimental Investigation ◽  
Vortex Shedding ◽  
Separated Flow ◽  
Flow Region ◽  
Separated Flows ◽  
Two Dimensional ◽  
Layer Behavior ◽  
Low Speed Wind Tunnel

An experimental investigation of the heat transfer from the base of a two-dimensional wedge-shaped body to the separated-flow region was conducted in a low-speed wind tunnel. The Stanton number has been determined as a function of Reynolds number for two geometries that are representative of heat-exchanger surfaces. The heat transfer is found to be comparable in magnitude to that for attached flows. An analysis based on the mechanisms of vortex shedding and boundary-layer behavior is developed. The analysis agrees fairly well with the data and indicates the parameters governing base heat transfer.

Turbulent Boundary Layer Heat Transfer on Curved Surfaces

1979 ◽  
Vol 101 (3) ◽  
pp. 521-525 ◽  
Author(s):  
R. E. Mayle ◽  
M. F. Blair ◽  
F. C. Kopper
Keyword(s):  
Heat Transfer ◽  
Boundary Layer ◽  
Turbulent Boundary Layer ◽  
Convex Surface ◽  
Concave Surface ◽  
Turbulent Shear ◽  
Two Dimensional ◽  
Streamline Curvature ◽  
Turbulent Shear Stress ◽  
Two Dimensional Flow

Heat transfer measurements for a turbulent boundary layer on a convex and concave, constant-temperature surface are presented. The heat transferred on the convex surface was found to be less than that for a flat surface, while the heat transferred to the boundary layer on the concave surface was greater. It was also found that the heat transferred on the convex surface could be determined by using an existing two-dimensional finite difference boundary layer program modified to take into account the effect of streamline curvature on the turbulent shear stress and heat flux, but that the heat transferred on the concave surface could not be calculated. The latter result is attributed to the transition from a two-dimensional flow to one which contained streamwise, Taylor-Go¨rtler type vortices.

The Effect of Free-Stream Turbulence on Heat Transfer From a Rectangular Prism

1984 ◽  
Vol 106 (2) ◽  
pp. 268-275 ◽  
Author(s):  
D. C. McCormick ◽  
F. L. Test ◽  
R. C. Lessmann
Keyword(s):  
Heat Transfer ◽  
Pressure Gradient ◽  
Transfer Rate ◽  
Free Stream ◽  
Two Dimensional ◽  
Free Stream Turbulence ◽  
Favorable Pressure Gradient ◽  
Temperature Heat ◽  
Predicted Values ◽  
Rectangular Body

This paper discussses the effect of free-stream turbulence on the constant temperature heat transfer rate from the surface of a two-dimensional rectangular body that is subject to a strongly favorable pressure gradient. Free-stream turbulence levels of 2 to 5 percent enhanced the heat transfer by 48 to 55 percent over predicted laminar values. Free-stream turbulence levels of 10 to 35 percent produced heat transfer results that behaved in some aspects as turbulent predictions, although considerably enhanced in magnitude over the predicted values.

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