In the avionics industry, regulatory agencies and standards organizations, such as Federal Aviation Regulation (FAR) [1], Aeronautical Radio, Inc. (ARINC) [2], and Radio Technical Commission for Aeronautics (RTCA) [3], have developed sets of test procedures that help design engineers test and verify their designs and prevent any safety-threatening failures. Too often, however, … [Read more...]
Acoustic noise emission and communication systems in the next century
Acoustic noise emission is one of several physical design issues addressed during the design of telecommunications and information technology equipment. In most systems, noise is a by-product of the air-movers used for system cooling. The amount of heat dissipated in electronic systems cooled by forced convection is directly proportional to volumetric flow rate. The flow rate, … [Read more...]
Cooling Electronics at High Altitudes Made Easy
Introduction High altitude air cooling has always been somewhat of a mystery to the uninformed. The first reaction to the situation is that there is just not enough air at altitudes greater than six kilometers (20,000 ft). At times this may be true, but many things can be done to improve the cooling and obtain an acceptable design. The most important thing to remember when … [Read more...]
Thermal management of outdoor enclosures using phase change materials
Telephone equipment has traditionally been housed in large buildings, sheds and outdoor cabinets. The cooling of these facilities has been carried out using traditional methods. However, in many of the new systems being developed and deployed such as broadband ISDN, cellular and/or cable, heat dissipation densities will increase substantially [1]. Furthermore, the introduction … [Read more...]
Forced convection cooling of airborne electronics
Figure 1. AFT description Fin pitch = 25.01 per in = 985 per mPlate spacing, b = 0.200 in = 5.08 x 10-3 m Fin Length = 0.111 in = 2.8 x 10-3 m Flow passage hydraulic diameter 4rh = 0.004905 ft = 1.50 x 10-3 m Fin metal thickness = 0.004 in = 0.102 x 10-3 m Total heat transfer area/volume between plates, ß = 719.4 ft2 / ft3 = 2,360 m2 / m3 Fin area / total area = … [Read more...]