Analysis of Heat Transfer and Fluid Flow in Two-Phase Thermosyphon Loop with Minichannels

The present paper offers an analysis of heat transfer and fluid flow in two phase thermosyphon loop with minichannels. A one-dimensional model of two-phase flow and heat transfer in a closed thermosyphon loop with minichannels was examined. The created general model is based on mass, momentum, and energy balances in the evaporators, rising tube, condensers and the falling tube. The separate two-phase flow model is used in calculations. The numerical results obtained for the selected heater and cooler using the general model of thermosyphon loop indicate that the mass flux increases with increasing length of the heated section and decreases with increasing length of the cooled section of the loop. It was found that the heat transfer coefficient for flow boiling and flow condensation in the steady state increases with increasing heat flux in the heater and cooler with minichannels, respectively. The design and configuration of heaters and coolers has a considerable impact on the efficiency of thermosyphon loop. These factors make it possible to optimize the computer processor cooling.

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