Research on Heat Transfer Enhancement of Vortex-Induced Vibration of Side-by-Side Double Tubes

Abstract

The fluid-induced vibration heat transfer enhancement technology has great potential, because it can effectively improve the heat transfer efficiency without consuming additional energy. A reasonable design of the elastic heat exchange tube bundle structure is the key to the engineering application of this technology. In this paper, the effects of flow velocity and the center distance on the characteristics of vortex- induced vibration heat transfer in side-by-side double circular tubes are studied. We demonstrate that, when the center distance is no more than (outer diameter), the interference effect of the flowfield around the two tubes is greater, and the amplitude of the double tube is small. However, with the increase of , the flowfield interference decreases. Within the scope of this paper, two modes of vibration are obtained: in-phase vibration and out-of-phase vibration. When and , the fluid vortex-induced elastic supported side-by-side double circular tubes’ vibration can enhance heat transfer. Especially, when , the heat transfer enhancement effect is the strongest, reaching 14.5%. However, when , the heat transfer enhancement effect is not obvious. The research on the heat transfer characteristics of fluid flowing around the static double tube shows that when the distance is small, the flow velocity around the static tubes is larger, resulting in a higher surface average heat transfer coefficient, and as the distance increases, the heat transfer coefficient decreases.