Heat transfer and entropy generation for forced convection through a microduct of rectangular cross-section: Effects of velocity slip, temperature jump, and duct geometry

A numerical study of heat transfer in 90 deg, constant cross section curved duct, steady, laminar, flow is presented. The work is aimed primarily at characterizing the effects on heat transfer of duct geometry and entrance conditions of velocity and temperature by considering, especially, the role of secondary motions during the developing period of the flow. Calculations are based on fully elliptic forms of the transport equations governing the flow. They are of engineering value and are limited in accuracy only by the degree of computational mesh refinement. A comparison with calculations based on parabolic equations shows how the latter can lead to erroneous results for strongly curved flows. Buoyant effects are excluded from the present study so that, strictly, the results apply to heat transfer flows in the absence of gravitational forces such as arise in spacecraft.

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Forced-convection freezing heat transfer characteristics in a return bend with a rectangular cross section

Heat and Mass Transfer ◽

10.1007/bf01602764 ◽

1995 ◽

Vol 30 (4) ◽

pp. 205-214 ◽

Cited By ~ 1

Author(s):

M. Tago ◽

S. Fukusako ◽

M. Yamada ◽

A. Horibe

Keyword(s):

Heat Transfer ◽

Forced Convection ◽

Cross Section ◽

Rectangular Cross Section ◽

Heat Transfer Characteristics ◽

Transfer Characteristics

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Heat Transfer Around Sharp 180 Degree Turns in Smooth Rectangular Channels

Volume 3: Heat Transfer; Electric Power ◽

10.1115/85-gt-122 ◽

1985 ◽

Author(s):

D. E. Metzger ◽

M. K. Sahm

Keyword(s):

Heat Transfer ◽

Reynolds Number ◽

Forced Convection ◽

Cross Section ◽

Rectangular Cross Section ◽

Side Wall ◽

Bottom Wall ◽

Channel Depth ◽

Nusselt Numbers ◽

Rectangular Channels

Measured Nusselt numbers are presented for forced convection within and around sharp 180 degree turns in smooth channels of rectangular cross section. Separately determined top wall, bottom wall, and side wall values are presented individually along with azimuthal averages. The geometry of the channels and connecting turn is characterized by parameters W*, the ratio of upstream and downstream channel widths; D*, the non-dimensional channel depth; and H*, the non-dimensional clearance at the tip of the turn. Results from nine combinations of these parameters are presented at several values of channel Reynolds number to illustrate the effect of turn geometry on the heat transfer distributions.

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Heat Transfer Around Sharp 180-deg Turns in Smooth Rectangular Channels

Journal of Heat Transfer ◽

10.1115/1.3246961 ◽

1986 ◽

Vol 108 (3) ◽

pp. 500-506 ◽

Cited By ~ 60

Author(s):

D. E. Metzger ◽

M. K. Sahm

Keyword(s):

Heat Transfer ◽

Reynolds Number ◽

Forced Convection ◽

Cross Section ◽

Rectangular Cross Section ◽

Side Wall ◽

Bottom Wall ◽

Channel Depth ◽

Nusselt Numbers ◽

Rectangular Channels

Measured Nusselt numbers are presented for forced convection within and around sharp 180-deg turns in smooth channels of rectangular cross section. Separately determined top wall, bottom wall, and side wall values are presented individually along with azimuthal averages. The geometry of the channels and connecting turn is characterized by the parameters W*, the ratio of upstream and downstream channel widths; D*, the nondimensional channel depth; and H*, the nondimensional clearance at the tip of the turn. Results from nine combinations of these parameters are presented at several values of channel Reynolds number to illustrate the effect of turn geometry on the heat transfer distributions.

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