The effects of altitude, increased ambient temperature, and increased relative humidity on the board level forced convection typical of telecommunications products were systematically examined through numerical simulation and analytical techniques. Altitude was found to have the most significant impact on component temperature rise above inlet air temperature. Depending on the proportion of upstream-heating to self-heating for a given component, the component temperature rise above inlet air temperature was found to increase by 40% to 88% at when compared to the base line case at sea level. Inlet air temperature was found to translate linearly to component temperature increase. The second-order effects due to property changes with temperature were found to be less than 3% on the component temperature rise. The relative humidity was not found to significantly impact the component temperature rise at an inlet temperature of . However, the property changes at a inlet were more significant, and require further study. A temperature multiplier concept is introduced to aid practicing engineers in extrapolating data at standard conditions to the operating extremes.
Issue Section:
Technical Briefs
1.
Patel
, C.
, Sharma
, R.
, Bash
, C. E.
, Sharma
, R.
, Beitelmal
, A.
, and Malone
, C. G.
, 2005, “Smart Chip, System and Data Center Enabled by Advanced Flexible Cooling Resources
,” Proceedings of the 21st Annual IEEE Semi-Therm International Conference
, March 15-17, San Jose, CA, pp. 78
–85
.2.
Telcordia GR 63-CORE Issue 1, 1995, “
Network Equipment-Building System (NEBS) Requirements: Physical Protection
,” BellCore, www.telcordia.comwww.telcordia.com3.
Mansuria
, M. S.
, 1994, “Estimation of System Internal Air and Component Surface Temperatures at High Altitudes, Temperatures, and Relative Humidity
,” Proceedings of the 1994 International Electronics Packaging Conference
, Sept. 25-28, Atlanta, GA, pp. 122
–130
.4.
Wong
, H.
, and Peck
, R. E.
, 2001, “Experimental Evaluation of Air-Cooling Electronics at High Altitudes
,” ASME J. Electron. Packag.
1043-7398, 123
(4
), pp. 356
–365
.5.
Rhee
, J.
, and Azar
, K.
, 1999, “Adjusting Temperature Data for High Altitude
,” Electronics Cooling Magazine
5
(3
), pp. 44
–45
.6.
Anderson
, A.
, and Moffat
, R. J.
, 1992, “The Adiabatic Heat Transfer Coefficient and the Superposition Kernel Function: Part I–Data for Arrays of Flatpacks for Different Flow Conditions
,” ASME J. Electron. Packag.
1043-7398, 114
(1
) pp. 14
–21
.7.
Sparrow
, E. M.
, Neithammer
, J. E.
, and Chaboki
, A.
, 1982, “Heat Transfer and Pressure Drop Experiments in Air-Cooled Electronic-Component Arrays
,” J. Thermophys. Heat Transfer
0887-8722, 25
(7
), pp. 961
–973
.8.
Wirtz
, R. A.
, and Dykshoorn
, P.
, 1984, “Heat Transfer From Arrays of Flat Packs in a Channel Flow
,” Proceedings of the Fourth Annual International Electronics Packaging Society
, October, Baltimore
, pp. 318
–326
.9.
Faghri
, M.
, and Sridhar
, S.
, 1991, “Entrance Heat Transfer Correlation for Air Cooling of Array of Rectangular Blocks
,” Heat Transfer Enhancement in Electronic Cooling
, ASME-HTD-Vol. 183
, pp. 7
–11
.10.
Faghri
, M.
, Lessman
, R. C.
, and Sridhar
, S.
, 1989, “A Preliminary Experimental Study of Forced Air Cooling of Rectangular Blocks Encountered in Electronic Equipment
,” ASME Winter Annual Meeting
, December 10–15, San Francisco, 123
, pp. 1
–6
.11.
Molki
, M.
, and Faghri
, M.
, 2000, “Temperature of In-line Array of Electronic Components Simulated by Rectangular Blocks
,” Electron. Cooling Mag.
, 6
(2
), pp. 26
–32
.12.
Molki
, M.
, Faghri
, M.
, and Ozbay
, O.
, 1993, “A New Correlation for Pressure Drop in Arrays of Rectangular Blocks in Air-cooled Electronoic Units, General Papers in Heat Transfer-Natural and Forced Convection
,” J. Fluids Eng.
0098-2202, 116
, pp. 856
–886
.13.
Garimella
, S. V.
, and Eibeck
, P. A.
, 1990, “Onset of Transition in the Flow Over a Three-Dimensional Array of Rectangular Obstacles
,” Thermal Modeling and Design of Electronic Systems and Devices
, ASME-HTD Vol. 153
, pp. 1
–6
.14.
Lehmann
, G. L.
, and Wirtz
, R. A.
, 1985, “The Effect of Variations in Stream-Wise Spacing and Length on Convection From Surface Mounted Rectangular Components
,” Heat Transfer in Electronic Equipment-
, ASME-HTD 48
, pp. 39
–48
.15.
Choi
, Y. M.
, and Park
, K. A.
, 1988, “Forced Convection Heat Transfer in a Channel With Arrays of Simulated Microelectronic Chips
,” Proceedings of the First KSME-JSME Thermal and Fluids Engineering Conference
, November 1-3, Seoul
, South Korea, pp. 2
–371
.16.
Wirtz
, R. A.
, and Chen
, W.
, 1991, “Laminar-Transitional Convection From Repeated Ribs in a Channel
,” Heat Transfer in Electronic Equipment, ASME-HTD 171
, pp. 89
–94
.17.
Hollworth
, B. R.
, and Fuller
, H. A.
, 1987, “Heat Transfer and Pressure Drop in a Staggered Array of Aircooled Components
,” Proceeding of the International Symposium on Cooling Technology for Electronic Equipment
, March 18-21, Honolulu
, pp. 732
–748
.18.
Anderson
, A.
, 1994, “Decoupling Convective and Conductive Heat Transfer Using the Adiabatic Heat Transfer Coefficient
,” ASME J. Electron. Packag.
1043-7398, 116
(4
), pp. 310
–316
.19.
Batchelder
, K. A.
, and Eaton
, J. K.
, 2001, “Practical Experience With the Discrete Green’s Function Approach to Convective Heat Transfer
,” ASME J. Heat Transfer
0022-1481, 123
(1
), pp. 70
–76
.20.
Wirtz
, R. A.
, 1996, “Chapter 3: Forced Air Cooling of Low Profile Package Arrays
,” Air Cooling Technology for Electronic Equipment
, S. J.
Kim
and S. W.
Lee
, eds., CRC
, Boca Raton, FL, pp. 81
–102
.21.
White
, F. M.
, 2003, Fluid Mechanics
, 5th ed., McGraw–Hill
, Boston, p. 72
.22.
Belady
, C. L.
, 1996, “Design Considerations for Air Cooling Electronic Systems in High Altitude Conditions
,” IEEE Trans. Compon., Packag. Manuf. Technol., Part A
1070-9886, 19
(4
), pp. 495
–500
.23.
Rhee
, J.
, and Wong
, G.
, 2004, “Characterization of Airflow Impedance for Two Types of Telecommunications Chassis
,” Proceedings of the Semi-Therm International Conference
, March 9-11, San Jose, CA, pp. 161
–167
.24.
Moffat
, R. J.
, Arvizu
, D. E.
, and Ortega
, A.
, 1985, “Cooling Electronic Components: Forced Convection Experiments with an Air-Cooled Array
,” Heat Transfer in Electronic Equipment, ASME-HTD 48
, pp. 17
–27
.Copyright © 2006
by American Society of Mechanical Engineers
You do not currently have access to this content.
