RT Journal Article
ID 46540f29777268de
A1 Herman, Cila
A1 Kang, Eric
T1 An Experimantal Study of Convective Heat Transfer Enhancement in a Grooved Channel Using Cylindrical Eddy Promoters
JF Journal of Enhanced Heat Transfer
JO JEH(T)
YR 2001
FD 2001-12-01
VO 8
IS 6
SP 353
OP 371
AB We visualize oscillating temperature fields in the grooved channel with cylindrical eddy promoters using real-time holographic interferometry combined with high-speed cinematography. Flow transition from stable, laminar to oscillatory occurs around Re = 450. The addition of cylindrical eddy promoters improves the mixing and heat transfer across the shear layer at the groove lip. Vortices shed downstream of the cylinders induce oscillations more vigorous than do the self-sustained Tollmien-Schlichting waves alone in the more stable situation in the basic grooved channel. For Reynolds numbers ranging from 790 to 1580, the experimentally determined Nusselt numbers for the grooved channel with cylinders are roughly twice the magnitude of those measured for the basic grooved channel. The cylinder provides a flow obstruction, forcing the fluid to accelerate through the constriction between the block and the cylinder, effecting larger local Nusselt numbers along the trailing edge of the block's top surface. Pressure drop data suggest that for Re < 1000 the pressure drop penalty in the enhanced geometry is only moderately higher than for the basic grooved channel.
PB Begell House
LK http://dl.begellhouse.com/journals/4c8f5faa331b09ea,247e464779c7bb40,46540f29777268de.html