The effect of altitude on electronic cooling is evaluated experimentally. Material properties of air vary as a function of altitude due to changes in atmospheric pressure and temperature. These changes have a negative impact on the heat transfer effectiveness and result in higher component temperature when compared to sea level conditions. Experiments are carried out in a hypobaric chamber using electronic printed circuit boards populated with heated rectangular blocks placed in a small wind tunnel. The altitude is varied between 0 and 5000 m above sea level and the air speed is varied between 1 and 5 m/s. The results show the local adiabatic heat transfer coefficient and thermal wake function diminish with altitude. This information is useful for design and analysis of electronic equipment for operation over a range of altitudes and air speeds typically encountered in forced air convection cooling applications.

Issue Section:
Additional Technical Papers
Keywords:
printed circuit testing, heat transfer, forced convection, cooling, printed circuit design
Topics:
Convection, Cooling, Flow (Dynamics), Heat transfer coefficients, Seas, Temperature, Wakes, Heating, Design, Wind tunnels, Heat transfer
1.
Hall, D. A., 1989, “Prediction of Electronic Component Temperatures at High Altitude Using Low Altitude Measurements,” Proceeding Fifth Annual IEEE Semiconductor Thermal Measurement and Management Symposium, pp. 121–124.
2.
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, pp. 122–130.
3.
Steinberg, D. S., 1991, Cooling Techniques for Electronic Equipment, Wiley, New York.
4.
Vogel, M. R., 1996, “Thermal Performance of Air-Cooled Hybrid Heat Sinks for a Low Velocity Environment,” Proceedings of the Thirteenth Annual IEEE Semiconductor Thermal Measurement and Management Symposium, pp. 111–121.
5.
Belady, C. L., 1996, “Design Considerations for Air Cooling Electronic Systems in High Altitude Conditions,” Proceedings of the Thirteenth Annual IEEE Semiconductor Thermal Measurement and Management Symposium, Austin, pp. 111–121.
6.
Faghri, M., Molki, M., and Asako, Y., 1996, “Air Cooling Technology for Electronic Equipment,” Chapter 2, Entrance Design Correlations for Circuit Boards in Forced-Air Cooling, CRC Press, Boca Raton, pp. 47–80.
7.
Wirtz, R. A., 1996, “Air Cooling Technology for Electronic Equipment,” Chapter 3, Forced Cooling of Low-Profile Package Arrays, CRC Press, Boca Raton, pp. 81–101.
8.
Arvizu, D. E., and Moffat, R. J., 1982, “The Use of Superposition in Calculating Cooling Requirements for Circuit Board Mounted Electronic Components,” IEEE Proceedings of the 32nd Electronic Components Conference, San Diego, pp. 133–144.
9.
Moffat
,
R. J.
, and
Anderson
,
M. J.
,
1990
, “
Applying Heat Transfer Coefficient Data to Electronics Cooling
,”
ASME J. Heat Transfer
,
112
, pp.
882
–
890
.
10.
Anderson
,
A. M.
, and
Moffat
,
R. J.
,
1992
, “
The Adiabatic Heat Transfer Coefficient and the Superposition Kernel Function: Part 1 - Data for Arrays of Flatpacks for Different Flow Conditions
,”
ASME J. Electron. Packag.
,
114
, pp.
14
–
21
.
11.
Anderson
,
A. M.
, and
Moffat
,
R. J.
,
1992
, “
The Adiabatic Heat Transfer Coefficient and the Superposition Kernel Function: Part 2 - Modeling Flatpack Data as a function of Channel Turbulence
,”
ASME J. Electron. Packag.
,
114
, pp.
22
–
28
.
12.
Wong, H., 1999, “Experimental Investigation of Air Cooling Electronics at High Altitudes,” Master’s thesis Arizona State University, Arizona.
13.
Azar, K., 1997, Experimental Techniques in Electronic Cooling, CRC Press, Boca Raton, FL.
14.
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
.
15.
Anderson
,
A. M.
,
1994
, “
Decoupling Convective and Conductive Heat Transfer Using the Adiabatic Heat Transfer Coefficient
,”
ASME J. Electron. Packag.
,
116
, pp.
310
–
316
.
16.
Telecordia GR-63-CORE Issue 1, 1995, “Network Equipment-Building System (NEBS) Requirements: Physical Protection,” Bellcore.
Copyright © 2001
 by ASME
You do not currently have access to this content.