Improvement of cooling performance for electronic devices by nucleate boiling of immisible mixtures

Abstract

The employment of immiscible mixtures in nucleate boiling improves the cooling performance drastically. Increase of CHF is possible by high subcooling of less-volatile liquid compressed by high-vapor pressure of more-volatile component. In addition, the reduction of surface temperature from that of pure less-volatile liquid is resulted from the co-existed vapor of more-volatile component. And the increase of pressure above the atmospheric keeping low liquid temperature is possible to prevent the mixing of incondensable gases. Furthermore, boiling can be initiated at lower surface temperature, which is required for the cooling of e.g. automobile inverters accompanied by large variation of thermal load. The performance of immiscible mixtures in nucleate boiling are summarized with reference to new data for Novec7100/water and FC72/ethanol and existing data obtained by the present authors.