0
Research Papers

Natural Convection Immersion Cooling With Enhanced Optical Performance of Light-Emitting Diode Systems

[+] Author and Article Information
Enes Tamdogan

Department of Mechanical Engineering,
Faculty of Engineering,
Ozyegin University,
Cekmekoy,
Istanbul 34794, Turkey
e-mail: enestamdogan@gmail.com

Mehmet Arik

Department of Mechanical Engineering,
Faculty of Engineering,
Ozyegin University,
Cekmekoy,
Istanbul 34794, Turkey
e-mail: mehmet.arik@ozyegin.edu.tr

1Corresponding author.

Contributed by the Electronic and Photonic Packaging Division of ASME for publication in the JOURNAL OF ELECTRONIC PACKAGING. Manuscript received October 11, 2014; final manuscript received August 28, 2015; published online October 15, 2015. Assoc. Editor: Shi-Wei Ricky Lee.

J. Electron. Packag 137(4), 041006 (Oct 15, 2015) (8 pages) Paper No: EP-14-1089; doi: 10.1115/1.4031480 History: Received October 11, 2014; Revised August 28, 2015

Electronics driven at high currents may experience local hot spots, which may cause thermal degradation or even catastrophic failures. This common problem occurs at light-emitting diode (LED) chips and it is not easily observed by end-users. Driving over 700 mA over a 1 mm2 chip is expected to generate local temperature gradients. In addition, bonding failures at manufacturing or during operation (cracks, delamination, etc.) may also lead to local hot spots. Therefore, possible hot spots over an LED chip have turned attention to direct cooling with dielectric liquids comprises the current study. Computational and experimental studies have been performed to understand the impact of conduction and alternatively convection with various dielectric fluids to abate local hot spots in a multichip LED light engine. To capture the local temperature distributions over the LED light engine with a dome in the domain especially over the LED chip; first, computational models have been built with a commercial computational fluid dynamics (CFD) software. Later, attention has been turned into experimental validation by using a multichip high brightness LED (HB LED) light engine. An optothermal evaluation has been made at single and multiphase heat transfer modes with dielectric fluids (LS5252, HFE7000, and silicone oil, etc.) to compare with a series of CFD models and experimental studies. While multiphase liquid-cooled LED system has a better cooling performance but lower optical extraction, single-phase liquid-cooled LED system has shown a reasonable thermal performance with a 15% enhancement at light extraction.

Copyright © 2015 by ASME
Your Session has timed out. Please sign back in to continue.

References

Mehmet, A. , Anant, S. , Stanton, W. , and Joseph, S. J. , 2012, Energy Efficient Solid State Lighting Systems, Vol. 5, World Scientific, Singapore.
Liulin, Y. , Liu, S. , Chen, M. , and Xiaobing, L. , 2006, “ Thermal Analysis of High Power LED Array Packaging With Microchannel Cooler,” 7th International Conference on Electronic Packaging Technology (ICEPT '06), Shanghai, Aug. 26–29.
Xiaobing, L. , and Liu, S. , 2006, “ A Closed Micro Jet Cooling System for High Power LEDs,” 7th International Conference on Electronic Packaging Technology (ICEPT '06), Shanghai, Aug. 26–29.
Adam, C. , Ha, M. , and Graham, S. , 2007, “ Thermal Management Methods for Compact High Power LED Arrays,” Proc. SPIE, 6669, p. 66690Z.
Owen, S. , Gupta, M. P. , Mukhopadhyay, S. , and Kumar, S. , 2014, “ On-Chip Power Generation Using Ultra-Thin Thermoelectric Generators,” ASME J. Electron. Packag., 137(1), p. 011005. [CrossRef]
Madhour, Y. , d'Entremont, B. P. , Marcinichen, J. B. , Michel, B. , and Thome, J. R. , 2014, “ Modeling of Two-Phase Evaporative Heat Transfer in Three-Dimensional Multicavity High Performance Microprocessor Chip Stacks,” ASME J. Electron. Packag., 136(2), p. 021006. [CrossRef]
Icoz, T. , Verma, N. , and Jaluria, Y. , 2006, “ Design of Air and Liquid Cooling Systems for Electronic Components Using Concurrent Simulation and Experiment,” ASME J. Electron. Packag., 128(4), pp. 466–478. [CrossRef]
Thiagarajan, N. , Bhavnani, S. H. , and Narayanan, V. , 2015, “ Self-Propelled Sliding Bubble Motion Induced by Surface Microstructure in Pool Boiling of a Dielectric Fluid Under Microgravity,” ASME J. Electron. Packag., 137(2), p. 021009. [CrossRef]
Wang, P. , McCluskey, P. , and Bar-Cohen, A. , 2013, “ Two-Phase Liquid Cooling for Thermal Management of IGBT Power Electronic Module,” ASME J. Electron. Packag., 135(2), p. 021001. [CrossRef]
Mehmet, A. , Weaver, S. , Becker, C. , Hsing, M. , and Srivastava, A. , 2003, “ Effects of Localized Heat Generations Due to the Color Conversion in Phosphor Particles and Layers of High Brightness Light Emitting Diodes,” International Electronic Packaging Technical Conference and Exhibition (InterPACK'03), Maui, HI, July 6–11.
Enes, T. , Mehmet, A. , and Baris, D. M. , 2013, “ Direct Liquid Cooling of High Flux LED Systems: Hot Spot Abatement,” International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems, Burlingame, CA, July 16–18.
Mehmet, A. , Utturkar, Y. , and Weaver, S. , 2010, “ Immersion Cooling of Light Emitting Diodes,” 12th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), Las Vegas, NV, June 2–5.
ANSYS, 2009, ANSYS Fluent 12.0, Theory Guide, Ansys Inc., Canonsburg, PA.
Mehmet, A. , Yogen, U. , and Stanton, W. , 2010, “ Immersion Cooling of Light Emitting Diodes,” ITHERM 2010, Las Vegas, NV, June 2–5.
LabVIEW, 2013, All Systems—Instrumentation, National Instruments, Austin, TX.
3M Novec Engineered Fluid HFE-7200, 3M, St. Paul, MN, http://www.3m.com/
Mehmet, A. , Avram, B.-C. , and You, S. M. , 2007, “ Enhancement of Pool Boiling Critical Heat Flux in Dielectric Liquids by Microporous Coatings,” Int. J. Heat Mass Transfer, 50(5), pp. 997–1009.
Enes, T. , and Mehmet, A. , 2014, “ Numerical Comparisons of Passive and Active Cooling Strategies on LEDs With Optical Concerns: Natural, Forced and Immersion Cooling,” International Symposium on Convective Heat and Mass Transfer (ICHMT DL), Kusadasi, Turkey, June 8–13.
Mohapatra, S. , and Loikits, D. , 2005, “ Advances in Liquid Coolant Technologies for Electronics Cooling,” 21st IEEE Semiconductor Thermal Measurement and Management Symposium (STHERM), San Jose, CA, pp. 354–360.

Figures

Grahic Jump Location
Fig. 1

Schematic of CFD domain for the light engine with dome

Grahic Jump Location
Fig. 2

Chosen grid for analysis (mesh 1)

Grahic Jump Location
Fig. 3

Grid refinements through three different mesh structures and comparison of present CFD analysis with Mehmet et al. [14] experimental results

Grahic Jump Location
Fig. 4

Thermal and optical experimental setup

Grahic Jump Location
Fig. 5

Single- and multiphase natural convection experimental setup

Grahic Jump Location
Fig. 6

Spectral fluxes for three test samples at various currents

Grahic Jump Location
Fig. 7

Comparison of lumen extraction for various fluids

Grahic Jump Location
Fig. 8

Computational comparison of thermal capability of air and silicone

Grahic Jump Location
Fig. 9

Temperature distributions for air (left) and silicone (right) filled domes

Grahic Jump Location
Fig. 10

Computational comparison of thermal capability of air and HFE7200

Grahic Jump Location
Fig. 11

Computational comparison of thermal capability of air and FC72

Grahic Jump Location
Fig. 12

Temperature contour plots for each liquids and also silicone in comparison to dome with air: (a) system with open and close dome, (b) dome filled with air and silicone, (c) dome filled with air and water, (d) dome filled with air and HFE7000, (e) dome filled with air and HFE7200, and (f) dome filled with air and FC72

Grahic Jump Location
Fig. 13

Optical degradation with boiling

Grahic Jump Location
Fig. 14

Light extraction enhancement by liquid

Grahic Jump Location
Fig. 15

Effect of boiling over optical power

Grahic Jump Location
Fig. 16

Temperature rise over ambient for different liquids at various driving conditions

Grahic Jump Location
Fig. 17

Temperature rise over ambient for air, water, and NS15 at various driving conditions

Grahic Jump Location
Fig. 18

Nu and Pr values for dielectric liquids with NS fluids

Grahic Jump Location
Fig. 19

Nu and Gr values for dielectric liquids with NS15

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