Boiling of Immiscible Mixtures for Cooling of Electronics

Abstract

To satisfy the requirements for the cooling of small and large semiconductors operated at high heat flux density, an innovative cooling method using boiling heat transfer to immiscible liquid mixtures is proposed. Immiscible liquid mixtures discussed here are composed of more-volatile liquid with higher density and less-volatile liquid with lower density, and appropriate volumetric ratios become a key to realize high-performance cooling. The chapter reviews the experimental results obtained by the present authors, where critical heat flux accompanied by the catastrophic surface temperature excursion is increased up to 300 W/cm2 for FC72/water by using a flat heating surface of 40 mm in diameter facing upwards under the pressure 0.1 MPa. To apply the superior heat transfer characteristics in boiling of immiscible mixtures to flow boiling system, preliminary experiments using a horizontal heated tube are performed and the classification of flow pattern with liquid-liquid interface and corresponding heat transfer performance are discussed