Control of jet impingement heat transfer in crossflow by using a rib
Author
Summary, in English
Experimental studies are carried out to investigate the jet impingement heat transfer in crossflow by liquid crystal thermography (LCT). The aim is to assess the possibility of controlling heat transfer by using a rib. The crossflow Reynolds number spans from 80,000 to 160,000 and the velocity ratio ranges from 1.0 to 2.8. The results show that the presence of rib can significantly modify the heat transfer pattern of impinging jet. For all the tested cases, the presence of rib makes the Nusselt number profiles across the stagnation point change from a classical bell-shaped profile to a plateau-like pattern, indicating the enhanced heat transfer region expands more as the rib is present. In particular, the presence of rib has a more pronounced effect on the enhancement of heat transfer at lower velocity ratios (R = 1.0 and R = 1.4). However, in such cases, the local heat transfer in the rib corner region deteriorates. At higher velocity ratios (R = 2.0 and R = 2.8), the presence of rib makes the heat transfer rate more uniform, but meanwhile, it is found that the impinging jet effect tends to be weaker. (C) 2011 Elsevier Ltd. All rights reserved.
Department/s
Publishing year
2011
Language
English
Pages
4157-4166
Publication/Series
International Journal of Heat and Mass Transfer
Volume
54
Issue
19-20
Links
Document type
Journal article
Publisher
Pergamon Press Ltd.
Topic
- Energy Engineering
Keywords
- Heat transfer control
- Jet impingement
- Rib
- LCT
Status
Published
ISBN/ISSN/Other
- ISSN: 0017-9310