Experimental study on flow boiling heat transfer of high-pressure water in a mini-tube

Abstract

With the miniaturization of industrial equipment, cooling methods in microchannels has been more important in recent years. However, studies focusing on high-pressure-water flow boiling in mini-channels under are rare. Flow boiling of high-pressure water has a high cooling potential due to the properties of water. In this paper, flow boiling heat transfer experiments were carried out in a tube of 1 mm diameter. The maximum heat transfer coefficient is as high as ∼350 kW/(m2·K). Heat transfer coefficient decreases with mass flux, and increases with heat flux and inlet pressure, indicating the heat transfer mechanism is nucleate boiling. Phenomenological models in the literature were utilized to analyze the flow pattern. Slug flow and churn flow, in which bubbles are present in the liquid phase, appear in this paper. A new correlation was proposed, which has better accuracy when predicting the experimental results.