Influence of Artificial Roughness on Heat Transfer in the Rotating Flow

The results of an experimental study of the process of convective and boiling heat transfer in the vessel with stirrer for smooth and rough ring-shaped pipes are presented. It is established that creation of two-dimensional artificial roughness on the heated surface causes the essential (~100%) intensification of convective heat transfer. In case of boiling the influence of roughness appears on the initial stage of boiling and in case of fully developed nucleate boiling there was no intensification of heat transfer. The similitude equation for calculating convective heat transfer coefficient, which generalizes well experimental data both for the smooth and the rough surfaces is proposed.

Authors:

• T. Magrakvelidze
• N. Bantsadze
• N. Lekveishvili
• Kh. Lomidze

Keywords:

• boiling
• heat transfer
• roughness.

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