Tag Archives: cold plate

Latest Qpedia Now Available for Download

Qpedia Thermal eMagazine June 2013

Qpedia Thermal eMagazine June 2013

Qpedia Thermal eMagazine, Volume 7, Issue 6, has just been released and can be downloaded at: http://www.qats.com/Qpedia-Thermal-eMagazine/Back-Issues.

This month’s featured articles include:

Enhancing Heat Sink Performance Using Thermoelectric Coolers

With the increase in the power dissipation of components and the parallel reduction of their size, engineers and researchers across the globe have been predicting that the era of air cooling might come to an end. Even though in some applications, with very high power dissipations such as IGBTs, air cooling may not be adequate and liquid cooling is a must; air cooling will continue to be the first choice for most electronic cooling applications for many years to come. Advances in air cooling continue to extend its use and the implementation of thermoelectric coolers (TECs) in heat sink applications is one such effort.

Immersion Liquid Cooling for Servers in Data Centers

Data center designers and operators have invented many ways to improve the data center’s thermal efficiency, such as optimizing the rack layout and air conditioner location, separating cold aisles and hot aisles, optimizing the configuration of pipes and cables in under-floor plenum, introducing liquid cooling to high-power severs. While the above methods can improve the data center heat load management, they cannot dramatically reduce the Power Usage Effectiveness (PUE). This article reviews two relatively new solutions: active single-phase immersion cooling technology proposed by Green Revolution Cooling (GRC) and a passive two-phase immersion cooling technology proposed by the 3M Company.

Industry Developments: Piezoelectric Cooling

Piezoelectric fans and jets must overcome various materials, thermal and mechanical challenges to become widely used in electronics cooling, but because they consume just 1/150 of the electricity of circular fans, run with little noise and have no parts that will wear out, they remain of great interest. In this article, a number of issues are addressed, including the inverse effect of the piezoelectric phenomena and dual piezoelectric cooling jets.

Technology Review: Innovative Cold Plate Designs, 2007 – 2012

In this issue our spotlight is on innovative cold plate designs. There is much discussion about its deployment in the electronics industry, and these patents show some of the salient features that are the focus of different inventors.

& Cooling News featuring the latest product releases and buzz from around the electronics cooling industry.

Download the issue now.

Not a Qpedia subscriber? Subscribe Now for free at: http://www.qats.com/Qpedia-Thermal-eMagazine/Subscribe-to-Qpedia and see why over 18,000 engineers read Qpedia.

Did you know Qpedia also publishes a book series? The five volume set contains 248 in-depth articles, researched and written by veteran engineers. They address the most critical areas of electronics cooling, with a wide spectrum of topics and thorough technical explanation. Order Now.

New Qpedia Thermal eMagazine Published!

Qpedia Thermal eMagazine, Volume 6, Issue 11, has just been released and can be downloaded at: http://www.qats.com/Qpedia-Thermal-eMagazine/Back-Issues. Featured articles in this month’s issue include:

Honeycomb Heat Sinks for LEDs

LEDs, or light-emitting diodes, are a form of solid-state lighting. An LED light is often made of a small piece of semiconductor, an integrated optical lens used to shape its radiation pattern, and a heat sink, used to dissipate heat and maintain the semiconductor at low operating temperature. LED lights present many advantages over incandescent light sources, including lower energy consumption, longer lifetime, improved physical robustness, smaller size and faster switching. This article examines Ma et al’s  findings with respect to the honeycomb heat sink design employed in LEDs, which has proven to be highly efficient.

Characteristics of Thermosyphons in Thermal Management

With the increase of heat fluxes and shrinking chip sizes in electronics applications, there is a need to spread the heat from the small chip to the larger heat sink or to transport the heat to a location where there is ample space to remove the heat. Heat pipes, vapor chambers and thermosyphons have been introduced to undertake this task and, in this article, we focus on some aspects of the design of thermosyphons. The advantage of thermosyphons is that they have no capillary limit and can transport large amounts of heat over long distances.

Industry Developments: Heat Pipes Providing High Performance

Heat pipes are increasing in type and use for the benefits they provide. Because of their lower total thermal resistance, heat pipes transfer heat more efficiently and evenly than solid aluminum or copper. Heat pipes contain a small quantity of working fluid (e.g. water, acetone, nitrogen, methanol, ammonia). Learn the conclusions of a recent study that focused on the best working fluid and another study of heat pipes in outer space.

Technology Review: Cold Plates, 2010 to 2012

Qpedia continues its review of technologies developed for electronics cooling applications. We are presenting selected patents that were awarded to developers around the world to address cooling challenges. After reading the series, you will be more aware of both the historic developments and the latest breakthroughs in both product design and applications.

Cooling News featuring the latest product releases and buzz from around the electronics cooling industry.

Download the issue now.

Not a Qpedia subscriber? Subscribe Now for free at: http://www.qats.com/Qpedia-Thermal-eMagazine/Subscribe-to-Qpedia and see why over 18,000 engineers read Qpedia.

The New iFLOW-200 Tests and Measures the Thermal and Hydraulic Performance of Cold Plates

Advanced Thermal Solutions, Inc. (ATS) has released a new thermal test instrument, the iFLOW-200, which assesses the thermal and hydraulic characteristics of cold plates in electronics cooling. It can be used to simulate a wide range of conditions to optimize a cold plate’s performance before it is commercialized or prior to its use in an actual application.

 

The iFLOW-200 measures coolant temperatures from 0-70°C with the high accuracy of ± 1°C. Differential pressure of the coolant in the cold plate is measured up to 103,000 Pa (15 psi), with the precise accuracy of ± 1%. Distilled water is used as the reference coolant. For test comparisons, the systems coolingVIEW software can also calculate thermal resistance and pressure drop as a function of flow rate for selected liquids.

 

The instrument system includes a pair of K-type thermocouples for measuring temperature changes on the cold plate surface. Temperatures are monitored on the coolingVIEW interface.

 

The iFLOW-200 system features easy set up and operation to save time when evaluating different cold plate models. Designed for accuracy and convenience, the iFLOW-200 simply requires setting the starting and ending coolant flow rates, and choosing the dwell time, pumping power and other parameters. These are easily done on any PC using the systemd user-friendly application program.

The iFLOW-200 system features separate controller and hydraulics enclosures with USB connections. The hydraulic package includes a fluid level indicator, coolant inlets and outlets from/to the cold plate under test, ports for surface temperature thermocouples, and a fluid cooling system for its internal heat exchanger. The iFLOW-200 is also ideal for testing alternative liquids.

 

More information about the iFLOW-200 Cold Plate Characterization System can be found at http://www.qats.com/Products/Temperature-and-Velocity-Measurement/Instruments/iFLOW-200

How to implement localized thermal management of electronics through the use of cold plates

Cold plates are “aluminum or other material plates containing internal tubing through which a liquid coolant is forced, to absorb heat transferred to the plate by transistors and other components mounted on it.”

Lytron is one of the best in the business at producing cold plates and their site is chock full of excellent information on the different types and uses.  Including some basic comparisons. The following cold plate graph, from Lytron, compares the normalized thermal resistances of different cold plate technologies, enabling thermal performances to be compared independently of the cold plate part geometries. The lower the thermal resistance, the better the performance of the cold plate. As many cold plates are customized, a range of typical values is shown for each cold plate technology. All cold plate performances are compared using water as the cooling fluid.

cold plate technology comparison for thermal management

Many thermal management applications in electronics require a cold plate to remove the heat from discrete components laid out on a printed circuit board (PCB). In these circumstances, it is more efficient that the liquid does not completely fill the cold plate, but is only transferred to areas that need to be cooled.  With this kind of cold plate design, the required volumetric flow rate of the coolant will be significantly lower than if the entire cold plate was filled with liquid. ATS’s thermal labs white paper, “Localized Cooling  Using Cold Plates” covers the math and method on how to do this.  Our white paper is free to our readers on the qats.com web site, just click to this link to download your own free copy of our white paper, “Localized Cooling  Using Cold Plates