The worldwide market for tube-axial fans is very large and, as a consequence, the number of tube-axial suppliers is significant. This article will focus on the techniques that can be used to quickly compare various tube-axial fan product offerings, in order to provide a quick screen and minimize the number of suppliers that are submitted to a detailed evaluation. Supplier … [Read more...]
Highly emissive ion beam textured surfaces for improved cooling of electronic devices
Continuous improvements in the cooling of electronic systems will berequired to keep pace with the rapid development of higher power chips.Currently, effective cooling relies (in part) on high surface area heatexchangers. Further improvements could be realized by increasing thesurface area of these devices. However, increasing the size of heatexchanger components is not a … [Read more...]
A simple method to estimate heat sink air flow bypass
Introduction After selecting or designing a heat sink based upon a given air velocity orvolumetric flow rate through the fins, the thermal designer needs to determinethe total amount of flow which must be delivered in the duct or card passagecontaining the module w with heat sink. As shown in Figure 1, some of the flowwill go around or bypass the heat sink. In fact, depending … [Read more...]
Temperature measurement using optical fibers
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...]
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...]
