Natural convection and passive heat rejection from two independent heat sources maintained at different temperatures and above ambient) on single circuit boards (FR4 and copper clad FR4) are experimentally studied. The effect of heat source location on maximum power dissipation is presented for both horizontal and vertical orientations. Heat losses due to radiation, natural convection and board conduction are quantified. As long as the heat sources are more than 2 cm apart, they do not influence each other on the FR4 board. Vertical orientation increases the power dissipation in the components by up to 30% for the FR4 board and 15% for the copper clad board. Two ounces of copper cladding increases the overall power dissipation by 150–190%.
Issue Section:
Technical Papers
1.
Ortega, A., and Moffat, R.J., 1985, “Heat Transfer from an Array of Simulated Electronic Components: Experimental Results for Free Convection with and without a Shrouding Wall,” Heat Transfer in Electronic Equipment-1985, ASME-HTD Vol. 48, pp. 5–15.
2.
Moffat, R.J., and Ortega, A., 1986, “Buoyancy Induced Forced Convection,” Heat Transfer in Electronic Equipment-1986, ASME-HTD Vol. 57, pp. 135–144.
3.
Fujii, M., Tomimura, T., and Zhang, X., 1995, “Natural Air Cooling of an Array of IC Boards,” Advances in Electronic Packaging-1995, ASME-EEP Vol. 10, pp. 823–828.
4.
Milanez, L.F., and Bergles, A.E., 1986, “Studies on Natural Convection Heat Transfer from Thermal Sources on a Vertical Surface,” Heat Transfer 1986-Proceedings of the 8th International Heat Transfer Conference, Vol. 3, pp. 1347–1352.
5.
Chadwick
, M.L.
, Webb
, B.W.
, and Heaton
, H.S.
, 1991
, “Natural Convection from Two-Dimensional Discrete Heat Sources in a Rectangular Enclosure
,” Int. J. Heat Mass Transfer
, 34
, pp. 1679
–1693
.6.
Hadim
, A.
, and Ramot
, M.
, 1993
, “Natural Convection in an Enclosure with Discrete Heat Sources on the Vertical Walls
,” ASME J. Electron. Packag.
, 115
, pp. 444
–448
.7.
Park, S.K., 1999, “Natural Convection Air Cooling Between Vertical Parallel Plates with Heated protrusions Simulating Plate-Mounted Electronic Components Within an Enclosure,” Advances in Electronic Packaging-1999, ASME-EEP Vol. 26, pp. 501–509.
8.
Krane
, R.J.
, and Phillips
, T.J.
, 1991
, “Natural Convection Cooling of a Horizontally Oriented Component Board in a Low-Aspect-Ratio Enclosure
,” ASME J. Electron. Packag.
, 113
, pp. 301
–308
.9.
Ortega, A., and Lall, B.S., 1996, “Natural Convection Air Cooling of a Discrete Source on a Conducting Board in a Shallow Horizontal Enclosure,” Proceedings of the 12th IEEE SEMI-THERM Symposium, pp. 201–213.
10.
Eveloy
, V.
, Lohan
, J.
, and Rodgers
, P.
, 2000
, “A Benchmark Study of Computational Fluid Dynamics Predictive Accuracy for Component-Printed Circuit Board Heat Transfer
,” IEEE Trans. Compon., Packag. Manuf. Technol., Part A
, 23
, pp. 568
–577
.11.
Lohan
, J.
, Tiilikka
, P.
, Rodgers
, P.
, Fager
, C.-M.
, and Rantala
, J.
, 2000
, “Experimental and Numerical Investigation into the Influence of Printed Circuit Board Construction on Component Operating Temperature in Natural Convection
,” IEEE Trans. Compon., Packag. Manuf. Technol., Part A
, 23
, pp. 578
–586
.12.
Yu
, E.
, and Joshi
, Y.K.
, 2000
, “Natural Convection Air Cooling of Electronic Components in Partially Open Compact Horizontal Enclosures
,” IEEE Trans. Compon., Packag. Manuf. Technol., Part A
, 23
, pp. 14
–22
.13.
Adams
, V.H.
, Joshi
, Y.
, and Blackburn
, D.L.
, 1999
, “Three-Dimensional Study of Combined Conduction, Radiation, and Natural Convection from Discrete Heat Sources in a Horizontal Narrow-Aspect Ratio Enclosure
,” ASME J. Heat Transfer
, 121
, pp. 992
–1001
.14.
Pence, S., 2000, “Thermal Management of Portable Electronic Devices Using Phase Change Materials,” Bachelor’s of Chemical Engineering Thesis, Villanova University, 2000.
15.
Hodes
, M.
, Weinstein
, R.D.
, Pence
, S.J.
, Piccini
, J.M.
, Manzione
, L.
, and Chen
, C.
, 2002
, “Transient Thermal Management of a Handset Using Phase Change Material (PCM)
,” ASME J. Electron. Packag.
, 124
, pp. 419
–426
.16.
Anderson
, A.M.
, 1997
, “A Comparison of Computational and Experimental Results for Flow and Heat Transfer from an Array of Heated Blocks
,” ASME J. Electron. Packag.
, 119
, pp. 32
–39
.17.
Ostrach, S., 1952, “An Analysis of Laminar Free-Convection Flow and Heat Transfer About a Flat Plate Parallel to the Direction of the Generating Body Force,” Technical Note 2635, National Advisory Committee for Aeronautics, Washington D.C.
18.
Lienhard
, J.H.
, 1973
, “On the Commonality of Equations for Natural Convection from Immersed Bodies
,” Int. J. Heat Mass Transfer
, 16
, pp. 2121
–2123
.Copyright © 2004
by ASME
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