Performance Evaluation of Boiling Chamber With Enhanced Boiling and Condensing Surfaces for Efficient Warm Water Operation

Abstract Boiling and condensation are integrated within a boiling chamber to cool a heating surface, such as a computer substrate, with cooling water. A finned tube condenser with a total surface area of 48,440 mm2 is used, and the effect of different fill ratios (40% and 80%) is studied. The results indicate that the enhanced finned tube condenser performs exceptionally well in improving the overall boiling chamber performance. The enhanced boiling chamber is able to dissipate high heat fluxes from the computer substrates within the operating temperature limits of the substrates with warm water cooling. This enables use of higher coolant inlet temperatures enabling the use of dry cooling towers and reducing water consumption in a data center. With a fill ratio of 40% and coolant inlet temperature of 40 °C, the boiling chamber dissipated a heat flux of 178 W/cm2 at a surface temperature of 84 °C. With a lower coolant inlet temperature and a fill ratio of 80%, a heat flux of 177 W/cm2 was dissipated with a 20 °C coolant inlet temperature, resulting in the surface temperature of 79 °C. This shows the boiling chamber's ability to outperform even at elevated coolant temperatures. Further, the compact design of the boiling chamber is well-suited for its implementation in data center cooling.