0
TECHNICAL PAPERS

Experimental Investigation of Compact Evaporators for Ultralow Temperature Refrigeration of Microprocessors

[+] Author and Article Information
Robert Wadell

 Intel Corporation, 1900 Prairie City Road, FM1-88, Folsom, CA 95630robert.p.wadell@intel.com

Yogendra K. Joshi

George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 771 Ferst Drive, Love Building, Room 338, Atlanta, GA 30332yogendra.joshi@me.gatech.edu

Andrei G. Fedorov

George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 771 Ferst Drive, Love Building, Room 307, Atlanta, GA 30332andrei.fedorov@me.gatech.edu

www.cryomech.com, www.kryotech.com, www.vapochill.com

J. Electron. Packag 129(3), 291-299 (Mar 28, 2007) (9 pages) doi:10.1115/1.2753919 History: Received May 24, 2006; Revised March 28, 2007

Microprocessor performance can be significantly improved by lowering the junction temperature, especially down to the deep subambient levels. This provides the strong motivation for the current study, which focuses on the design and thermohydraulic performance evaluation of high heat flux evaporators suitable for interfacing the microprocessor chip with a cascaded R134a∕R508b vapor compression refrigeration system at 80°C. Four compact evaporator designs are examined—a base line slit-flow structure with no microfeatures, straight microchannels, an inline pin fin array, and an alternating pin fin array—all fitting the same size envelope. Pressure drop and heat transfer measurements are reported and discussed to explain the performance of the various evaporator geometries for heat fluxes ranging between 20Wcm2 and 100Wcm2.

FIGURES IN THIS ARTICLE
<>
Copyright © 2007 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 2

Schematic of the cascaded VCR system used in this study A-test module, B-accumulator, C-1∕2hp low stage compressor, D-low stage oil separator, E-heat exchanger, F-flow meter, G-needle valve, H, I-shutoff valves, L-capillary tube, J-high stage compressor (1∕2hp), K-air cooled condenser, and F∕D-filter drier

Grahic Jump Location
Figure 1

Top view of the base line (bottom right), microchannel (bottom left), inline micropin fin (top left), and alternating micropin fins (top right) evaporators

Grahic Jump Location
Figure 12

Flow visualization of R508b evaporating in microchannels at 50g∕min and 70W of input power

Grahic Jump Location
Figure 3

Schematics of inner and outer test modules

Grahic Jump Location
Figure 4

Cross section of inner test module

Grahic Jump Location
Figure 5

Pressure drop for four different evaporators at 50g∕min, 60g∕min, and 70g∕min as a function of applied heat flux

Grahic Jump Location
Figure 6

Saturation temperatures of the refrigerant as a function of the dissipated heat flux for various flow rates for all evaporator types

Grahic Jump Location
Figure 10

Local chip temperatures as a function of imposed heat flux for the base line geometry at 50g∕min (see Fig. 4 for specific thermocouple locations)

Grahic Jump Location
Figure 11

Flow visualization of R508b evaporating in microchannels at 50g∕min and zero input power (evaporation is due to parasitic heat transfer from the ambient)

Grahic Jump Location
Figure 7

Boiling curves for four different evaporators at 50g∕min, 60g∕min, and 70g∕min.

Grahic Jump Location
Figure 8

Effective convective heat transfer for four different evaporators at 50g∕min, 60g∕min, and 70g∕min as a function of the exit refrigerant mixture quality

Grahic Jump Location
Figure 9

Maximum chip temperature for four different evaporators at 70g∕min, 60g∕min, and 50g∕min as a function of the dissipated heat flux at the chip surface

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In