Solutions containing drag reducing additives also show reduced heat transfer which limits their use in district heating and cooling recirculation systems where heat exchange is critical. In this study, static mixers A and B and honeycombs were installed at the entrance to a heat exchanger to break t
Drag-reducing and heat transfer characteristics of a novel zwitterionic surfactant solution
β Scribed by J.J. Wei; Y. Kawaguchi; F.C. Li; B. Yu; J.L. Zakin; D.J. Hart; Y. Zhang
- Publisher
- Elsevier Science
- Year
- 2009
- Tongue
- English
- Weight
- 475 KB
- Volume
- 52
- Category
- Article
- ISSN
- 0017-9310
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β¦ Synopsis
Experiments were conducted to study the drag-reduction and heat transfer performances of a newly synthesized zwitterionic surfactant solution (oleyl trimethylaminimide) in a two-dimensional channel. For testing the drag-reduction at subzero temperatures, a 20% ethylene glycol aqueous solution (EG/W) was used as solvent. The surfactant concentration ranged from 50 to 1000 ppm and the temperature was Γ5 and 25 Β°C, respectively. It was found that the novel zwitterionic surfactant solution showed both drag and heat transfer reduction characteristics, which were affected by concentration and temperature. The maximum drag-reduction was 83% at 25 Β°C for 200 ppm surfactant solution. The effects of addition of NaNO 2 to the surfactant solution were also investigated. For enhancing heat transfer of the surfactant drag-reducing flow, a destructive device, named Block, was designed and used in the experiments. The Block device has two contracting-expanding flow passages on both sides respectively with the central part blocked. It was found that the Block device can enhance the heat transfer performance of the novel zwitterionic surfactant solution to some extent while having a very small pressure drop penalty compared with other researcher's destructive devices due to the dominant action of elongational stress.
π SIMILAR VOLUMES
The drag reduction and heat transfer characteristics of water solutions with two kinds of surfactants (cetyltrimethylammonium bromide and dodecyltrimethylammonium chloride) in a straight pipe were investigated experimentally. The flow resistance and heat transfer of water solution flow with the two
drag-reducing ability after a period of continuous circulation. The effect of various metal ions and compounds on the viscoelas-The effective time varied from a few days to tens of days, ticity of a 12.5/5 m M sodium salicylate (NaSal)/tris(2-hydroxydepending on the components present in the loop. T