This study presents an experimental exploration of flow boiling heat transfer in a spiraling radial inflow microchannel heat sink. The effect of surface wettability, fluid subcooling levels, and mass fluxes are considered in this type of heat sink for use in applications with high fluxes up to 300 W/cm2. The design of the heat sink provides an inward radial swirl flow between parallel, coaxial disks that form a microchannel of 300 μm and 1 cm radius with a single inlet and a single outlet. The channel is heated on one side through a copper conducting surface, while the opposite side is essentially adiabatic to simulate a heat sink scenario for electronics cooling. Flow boiling heat transfer and pressure drop data were obtained for this heat sink device using water at near atmospheric pressure as the working fluid for inlet subcooling levels from 20 to 81°C and mean mass flux levels ranging from 184 to 716 kg/m2s. To explore the effects of varying surface wetting, experiments were conducted with two different heated surfaces. One was a clean, machined copper surface with water equilibrium contact angles in the range of 14–40°, typical of common metal surfaces. The other was a surface coated with zinc oxide nanostructures that are superhydrophilic with equilibrium contact angles measured below 10°. During boiling, increased wettability resulted in quicker rewetting and smaller bubble departure diameter as indicated by reduced temperature oscillations during boiling and achieving higher maximum heat flux without dryout. Reducing inlet subcooling levels was also found to reduce the magnitude of oscillations in the oscillatory boiling regime. The highest heat transfer coefficients were seen in fully developed boiling with low subcooling levels as a result of heat transfer being dominated by nucleate boiling. The highest heat fluxes achieved were during partial subcooled flow boiling at 300 W/cm2 with an average surface temperature of 134 °C and requiring a pumping power to heat rate ratio of 0.01%. The hydrophilic surface retained wettability after a series of boiling tests. Recommendations for use of this heat sink design in high flux applications is also discussed.
Skip Nav Destination
ASME 2015 13th International Conference on Nanochannels, Microchannels, and Minichannels collocated with the ASME 2015 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems
July 6–9, 2015
San Francisco, California, USA
Conference Sponsors:
- Heat Transfer Division
- Fluids Engineering Division
ISBN:
978-0-7918-5687-1
PROCEEDINGS PAPER
Boiling Heat Transfer Performance in a Spiraling Radial Inflow Microchannel Cold Plate Available to Purchase
Maritza Ruiz,
Maritza Ruiz
University of California, Berkeley, Berkeley, CA
Search for other works by this author on:
Claire M. Kunkle,
Claire M. Kunkle
University of California, Berkeley, Berkeley, CA
Search for other works by this author on:
Jorge Padilla,
Jorge Padilla
University of California, Berkeley, Berkeley, CA
Search for other works by this author on:
Van P. Carey
Van P. Carey
University of California, Berkeley, Berkeley, CA
Search for other works by this author on:
Maritza Ruiz
University of California, Berkeley, Berkeley, CA
Claire M. Kunkle
University of California, Berkeley, Berkeley, CA
Jorge Padilla
University of California, Berkeley, Berkeley, CA
Van P. Carey
University of California, Berkeley, Berkeley, CA
Paper No:
ICNMM2015-48406, V001T04A023; 10 pages
Published Online:
November 18, 2015
Citation
Ruiz, M, Kunkle, CM, Padilla, J, & Carey, VP. "Boiling Heat Transfer Performance in a Spiraling Radial Inflow Microchannel Cold Plate." Proceedings of the ASME 2015 13th International Conference on Nanochannels, Microchannels, and Minichannels collocated with the ASME 2015 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems. ASME 2015 13th International Conference on Nanochannels, Microchannels, and Minichannels. San Francisco, California, USA. July 6–9, 2015. V001T04A023. ASME. https://doi.org/10.1115/ICNMM2015-48406
Download citation file:
19
Views
Related Proceedings Papers
Enhancement of Pool Boiling Heat Transfer Using Nanostructured Surfaces on Aluminum and Copper
IMECE2009
Heat Transfer Characteristics and Flow Pattern Visualization for Flow Boiling in a Vertical Narrow Microchannel
InterPACK2018
Related Articles
Onset of Boiling, Heat Transfer, and Flow Patterns of Flow Boiling on the Superhydrophobic Porous Copper Surface in a Microchannel
J. Heat Transfer (August,2021)
Enhanced Subcooled Flow Boiling Heat Transfer in Microchannel With Piranha Pin Fin
J. Heat Transfer (November,2017)
High-Flux Thermal Management With Supercritical Fluids
J. Heat Transfer (December,2016)
Related Chapters
Thermal Design Guide of Liquid Cooled Systems
Thermal Design of Liquid Cooled Microelectronic Equipment
Completing the Picture
Air Engines: The History, Science, and Reality of the Perfect Engine
Outlook
Closed-Cycle Gas Turbines: Operating Experience and Future Potential