The effects of dissolved air in the dielectric liquid FC-77 on flow boiling in a microchannel heat sink containing 10 parallel channels, each 500 μm wide and 2.5 mm deep, were experimentally investigated. Experiments were conducted before and after degassing, at three flow rates in the range of 30 to 50 ml/min. The dissolved air resulted in a significant reduction in wall temperature at which bubbles were first observed in the microchannels. Analysis of the results suggests that the bubbles observed initially in the undegassed liquid were most likely air bubbles. Once the boiling process is initiated, the wall temperature continues to increase for the undegassed liquid, while it remains relatively unchanged in the case of the degassed liquid. Prior to the inception of boiling in the degassed liquid, the heat transfer coefficients with the undegassed liquid were 300–500% higher than for degassed liquid, depending on the flow rate. The heat transfer coefficients for both cases reach similar values at high heat fluxes (over 120 kW/m2) once the boiling process with the degassed liquid was well established. The boiling process induced a significant increase in pressure drop relative to single-phase flow; the pressure drop for undegassed liquid was measured to be higher than for degassed liquid once the boiling process became well established in both cases. Flow instabilities were induced by the boiling process, and the magnitude of the instability was quantified using the standard deviation of the measured pressure drop at a given heat flux. It was found that the magnitude of flow instability increased with increasing heat flux in both the undegassed and degassed liquids, with greater flow instability noted in the undegassed liquid.
Skip Nav Destination
ASME 3rd International Conference on Microchannels and Minichannels
June 13–15, 2005
Toronto, Ontario, Canada
Conference Sponsors:
- Nanotechnology Institute
ISBN:
0-7918-4185-5
PROCEEDINGS PAPER
Effects of Dissolved Air on Subcooled Flow Boiling of a Dielectric Coolant in a Microchannel Heat Sink Available to Purchase
Tailian Chen,
Tailian Chen
Purdue University, West Lafayette, IN
Search for other works by this author on:
Suresh V. Garimella
Suresh V. Garimella
Purdue University, West Lafayette, IN
Search for other works by this author on:
Tailian Chen
Purdue University, West Lafayette, IN
Suresh V. Garimella
Purdue University, West Lafayette, IN
Paper No:
ICMM2005-75157, pp. 89-96; 8 pages
Published Online:
November 11, 2008
Citation
Chen, T, & Garimella, SV. "Effects of Dissolved Air on Subcooled Flow Boiling of a Dielectric Coolant in a Microchannel Heat Sink." Proceedings of the ASME 3rd International Conference on Microchannels and Minichannels. ASME 3rd International Conference on Microchannels and Minichannels, Part B cont’d. Toronto, Ontario, Canada. June 13–15, 2005. pp. 89-96. ASME. https://doi.org/10.1115/ICMM2005-75157
Download citation file:
15
Views
Related Proceedings Papers
Related Articles
Effects of Dissolved Air on Subcooled Flow Boiling of a Dielectric Coolant in a Microchannel Heat Sink
J. Electron. Packag (December,2006)
High-Flux Thermal Management With Supercritical Fluids
J. Heat Transfer (December,2016)
Two-Phase Performance of a Hybrid Jet Plus Multipass Microchannel Heat Sink
J. Thermal Sci. Eng. Appl (February,2020)
Related Chapters
Experiment Investigation of Flow Boiling Process Including Cavitation in Micro-Channel
Inaugural US-EU-China Thermophysics Conference-Renewable Energy 2009 (UECTC 2009 Proceedings)
Forced Convection Subcooled Boiling
Two-Phase Heat Transfer
Outlook
Closed-Cycle Gas Turbines: Operating Experience and Future Potential