Tag Archives: thermal management

How to Understand Fan Curves and Optimum Operating Points


Fans, or other air movers, are a critical part of any system level thermal management solution. There are cases where a fan is not preferred, such as in medical equipment (see our earlier post on that topic here), some military applications and in some consumer applications. And, fans do present the unwanted chance of mechanical failure being introduced into a system.

In a white paper written by ebmpapst, they note that:

Fans create a flow of air, which they can then force through equipment that needs cooling. The necessary output is determined from the flow rate and the required static pressure. If the airflow through the equipment is restricted to any great extent by built-in components or bends and junctions, then this will lead to a loss of pressure; the fan will try to compensate for this by an increase in the static pressure, though the fan will have to work harder than in free air operation. The characteristic curve of the fan gives precise information about the flow rate at specific static pressures.

Understanding these curves is critical and ebmpapst has a good, introductory white paper to help you understand them. You can get your copy of their quick and useful read by clicking:  Fan Curves and Optimum Operating Points.

ATS, Inc. announces “on demand” Webinar for Thermal Engineers: Methodologies for Fan Characterization

ATS, Inc. is announcing a new “on-demand” webinar from our thermal engineering team, “Methodologies for Fan Characterization”. This webinar is ready for download and listening 24 hours day from the ATS web site.

Topics covered include:

  • What are the fan types and points of application?
  • Understanding how fans operate and the effect of bypass flow on their operation
  • Fan selection
  • Fan assemblies and their implementation
  • Use of fan laws for sizing
  • Managing acoustic noise
  • Fan characterization

To take part in this webinar, just click to our site to reach the webinar at: Methodologies for Fan Characterization

How to use fan trays in electronic enclosures for thermal management; an ATS Thermal Labs “how to” white paper

While heat sinks do a terrific job of moving heat from a hot chip, cool air (or another moving liquid) is very helpful to move that heat off the chip and out of the system. Individual fans are one way to approach this problem. Another is by use of a fan tray.

A fan tray is an array of fans put together in a removable tray of some kind. There are various types and configurations based on whether you need to move air for a computer server, telecomm central office equipment or medical equipment. Fan trays are very helpful in developing a system level thermal management solution.

While on the surface of it, a fan tray appears to be no more than a number of fans placed in a frame there is actually quite a bit more there. From the kinds of fans, to the circuitry used to control them, fan trays are really an air moving system that, when engineered right, can bring real benefit.

ATS’s Thermal white paper will give you a basic sense for what’s involved, so click to it at our site now, “How to use fan trays in electronic enclosures; an ATS Thermal Labs “how to” white paper.

Thermal Management of Medical Equipment is not just about keeping it cool; it might mean life or death for the patient

Yesterday we noted Thermacore’s new white paper, “Thermal Management for Today’s Medical Devices and Equipment“. As we noted yesterday, we couldn’t agree more with Thermacore’s premise. Here at ATS, our team thinks the topic of proper thermal management of medical equipment is vitally important to people’s lives. So important, we wanted to post a bit more about it.

Key trends we are seeing in thermal development in the medical industry:

  • Unquestioned Reliability
  • Instruments with greater accuracy and capability
  • Reduced size and miniaturization

Reliability is important on at least two levels. First, if the equipment is not reliable, the economic payback simply won’t be there for a physician, clinic or hospital. For example, CT scanner’s can cost up to $300,000. If it’s unreliable due to thermal stress, the payback investment might be twice as long as what would generally be seen.

The second reason for reliability is for patient and doctor confidence. Patients want to have confidence in the equipment they are being tested on. This can reduce their personal stress by trusting the results they will receive are accurate. Doctor’s want to be confident in the diagnostic equipment they are using. Doctor’s want to trust the data they get is accurate enough for them to determine a diagnosis.

The accuracy and diagnostic capability is important too. For any medical equipment to be useful the data collected has to be accurate or else a wrong diagnosis might occur.
The fallout from that reduced accuracy can be devastating as incorrect diagnosis may be formed leading to an incorrect course of healing for the patient. Poor thermal management of key components and entire systems can cause processors within the medical equpiment to overheat, slowdown and potentially return data errors.

Finally, reduced size and miniaturization can mean diagnostic equipment gets deployed more widely increasing it’s potential use and benefitting the health of the population where it is used. The packaging for this smaller equipment requires careful attention to the thermal design. Regardless of how low power the components used, the smaller the space, the more the airflow will be reduced and the increased likelihood for thermal stress and component malfunction.

Thermal management of electronics is critical to their functioning properly and being a tool that helps people’s health. At ATS, we have developed thermal management solutions, including heat sinks, for a variety of medical applications from EKG machines, to Defibrillators, to Ultrasound equipment and Tissue/DNA Analyzation instruments. To learn more about our thermal management consulting for medical equipment, please visit our web site at this link: ATS Thermal Management of Medical Applications. You can also drop us a line to tell us about your application and how we might help by clicking to our on-line engineering services request at our web site: Analysis and Design Services Request

How passive thermal management can help medical products engineers meet design challenges for cost, thermal performance & low noise

Thermacore has released a compelling white paper on the use of passive thermal technologies to cool medical equipment and devices. Thermal management of electronics is critically important. No one wants to get a report noting you have a health problem and this is especially true if that ill-health report is wrong due to a medical equipment malfunction due to overheating.

Thermacore’s white paper notes that:

The impressive capabilities of 21st century medical technology, from imaging equipment to surgical instruments and automated immunoassays, are in many ways a tribute to the advances in microprocessor computing power. However, more power means more heat, generally in a smaller space. And as greater demands for precision and reliability are placed on medical equipment, thermal control becomes more critical.

We couldn’t agree more. Even low power processors are being packed together to provide more cores for a given application. While a 1W or 2W processor might not be much, try putting 30 of those together in a shoe box!

Thermacore has some great input about how to address thermal management in medical electronics. Visit their article at their site: Thermal Management for Today’s Medical Devices and Equipment.

If you aren’t familiar with heat pipes and how they work, our team at ATS Thermal Labs has prepared a white paper describing how and why they work; you can find a copy at ATS’s Qpedia Archives by clicking to Heat Pipes; Heat Super Conductors. ATS also does Heat Pipe development, to learn more, email Mike Haskell, one of our Senior Thermal Engineers, at [email protected]