Introduction Fiber optic temperature measurement has been in use for decades1.The most prevalent methods are fluorescent and radiation thermometry, also knownas pyrometry. Fluorescent temperature measurement is used for lower-rangemeasurements from -200°C to +450°C. Pyrometry best covers ranges from100°C to 4,000°C, and is based on the physics of Planck's blackbodyradiation … [Read more...]
An introduction to thermoelectric coolers
Figure 1: Cross Section of a Typical TECouple Introduction Thermoelectric coolers are solid state heat pumps used in applications wheretemperature stabilization, temperature cycling, or cooling below ambient arerequired. There are many products using thermoelectric coolers, including CCDcameras (charge coupled device), laser diodes, microprocessors, blood analyzersand portable … [Read more...]
Thermal control of space electronics
Introduction Telecommunication satellites are all based on the same overall design usinga 3 axis stabilization process, in which the North and South panels act asradiators and so ensure heat removal. This basic principle is illustrated in Figure 1. The ever-increasing demandfor national and international space-based communications in parallel with theevolution of space … [Read more...]
Thermal resistance of interface materials as a function of pressure
A very large factor in reducing thermal interface resistance is theapplication of pressure. Even though much effort in recent years has beendevoted to improving the thermal conductivity of interface materials, thethermal conductivity of a material is only a piece of the heat transfer puzzle. As shown in Figure 1, the thermal resistance created by the material itself(RM) for a … [Read more...]
Minimizing acoustical noise in electronic systems
Introduction Air-moving devices (AMDs), such as fans and blowers used for cooling inelectronic systems invariably generate acoustical noise which must be consideredif people are exposed to the emitted noise. In this article, we discussquantitative measures for the description of noise, design guidelines for theselection of low noise air movers, upper limits for the noise … [Read more...]
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