Enhancement of Impingement Heat Transfer on a Flat Plate with Ribs

Impinging jets are widely used in industrial cooling systems for their high heat transfer characteristics at stagnation points. However, the heat transfer characteristics are low in the downstream direction. In order to improve the heat transfer coefficient further downstream, investigations introducing ribs on jet-cooled flat plates have been conducted. Most studies regarding the heat-transfer enhancement using a rib-roughened wall have dealt with the rib pitch. In this paper, we focused on the rib spacing and demonstrated that the rib spacing must be more than 6 times the nozzle width to improve heat transfer at Reynolds number Re=5.0×103 because it is necessary to have enough space to allow reattachment of flow behind the first rib.

Authors:

• M. Kito
• M. Takezaki
• T. Shakouchi
• K. Tsujimoto
• T. Ando

Keywords:

• Forced convection
• heat transfer
• impinging jet cooling
• rib roughened wall

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