Enhanced cooling using a swirling impinging air jet

Book · Sun Dec 31 04:00:00 EST 1995

OSTI ID:509287

Huang, L; El-Genk, M S ^[1]

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1. Univ. of New Mexico, Albuquerque, NM (United States)

A swirling jet design was developed that not only enhances heat transfer but also provides more uniform surface cooling than a straight impinging jet. Experiments were performed using both type jets of the same diameter (12.7 mm). Results showed that local and average Nusselt numbers for the swirling jet were significantly higher than those for the straight impinging jet. Higher Reynolds number and/or lower jet spacing increased Nusselt number values all along the heated surface. The uniformity of surface cooling; however, was realized only at large jet spacing (76.2 mm). For small jet spacing (12.7 and 25.4 mm), the increased turbulence brought about enhancement in heat transfer and produced a saddle-shaped radial distribution of the local Nusselt number, Nu(r). As jet spacing increased, the peak values of Nu(r) decreased, however, their radial location from the stagnation point increased. Eventually, at a large jet spacing of 76.2 mm, Nu(r) peaks disappeared and values in the vicinity of the stagnation point (r {le} d{sub j} mm) became smaller but almost uniform.

• OSTI ID: 509287
• Report Number(s): CONF-950828--; ISBN 0-7918-1702-4
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
AIR FLOW
AUGMENTATION
COOLING
ELECTRONIC EQUIPMENT
EXPERIMENTAL DATA
HEAT TRANSFER
JETS
TEMPERATURE CONTROL
VORTEX FLOW