Mist/steam cooling by a row of impinging jets

✍ Scribed by X Li; J.L Gaddis; T Wang

• Book ID: 104135766
• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 456 KB
• Volume: 46
• Category: Article
• ISSN: 0017-9310
• DOI: 10.1016/s0017-9310(02)00521-5

✦ Synopsis

Mist/steam cooling has been studied to augment internal steam-only cooling for advanced turbine systems. Water droplets generally less than 10 lm are added to 1.3 bar steam and injected through a row of four round jets onto a heated surface. The Reynolds number is varied from 7500 to 22,500 and the heat flux varied from 3.3 to 13.4 kW/m 2 . The mist enhances the heat transfer along the stagnation line and downstream wanes in about 3 jet diameters. The heat transfer coefficient improves by 50-700% at the stagnation line for mist concentrations 0.75-3.5% by weight. Off-axis maximum cooling occurs in most of the mist/steam flow but not in the steam-only flow. CFD simulation indicates that this off-axis cooling peak is caused by dropletsÕ interaction with the target walls.