By collecting and analyzing more relevant measurement data, electronic cooling systems can be designed for improved performance, reliability, and cost. It’s essential these measurements be as accurate as possible. Critical data points include component temperature, air temperature, air flow rate, and often air pressure. Accuracy becomes even more important when performing accelerated testing as seen in this post.
Research-grade instruments and specialized sensors, properly calibrated and operated, can measure chip temperatures and surrounding elements, such as local airflow. Separate instruments can be used to quantify specific conditions, but more real-use data is obtained when all points are collected simultaneously. Taken over a range of time and conditions, simultaneous measurements provide more accurate, actionable information. They also reduce the cost and set-up time for multiple studies.
Fig 1 – Input Ports for a Laboratory Instrument that Simultaneously Measures Air Velocity, Temperature and Pressure. [ATS]Fig 2 – High-quality Thermal Data Reduces Uncertainties in Cooling Solutions than Calculated Data. [ATS]
Accelerated Product Reliability Testing
Reliability testing at different temperatures and conditions is commonly performed to identify expected product life. When an electronic system is running, it continuously experiences temperature and power cycling. These fluctuations are typically normal, but should be factored into a comprehensive thermal profile study.
It’s not practical to wait years to see if a component fails. Accelerated life testing provides faster predictions. A commonly used predictive tool is the Arrhenius model shown below.
Accelerated life testing using the Arrhenius model is a method for predicting how long a product will last under normal conditions by running it at elevated temperatures for a shorter time. The temperature increase speeds up the same failure processes that would eventually occur in the field—compressing years of life into weeks of testing.
Accelerated life testing Arrhenius calculators can help estimate field lifetime, test duration, acceleration factors, activation energy, and field failure rates. These tools are useful when real-time qualification can’t be done. This is typical with electronic components and devices that need fast market introduction. One such calculator is found here: Accelerated Life Test Arrhenius Calculator. [1]
The Arrhenius Model handles pure thermal stress, while the Eyring Model includes temperature plus other active forces like humidity or voltage. [1,2]
Highly Accurate Thermal Instruments
Besides its design, a thermal instrument’s construction and calibration should be high quality, and not a source of more errors. Accurate, research-grade instruments are essential for valid engineering practices. Without them, reliability predictions for a new product are actually less reliable themselves.
Fig 3 – Candlestick Sensors are Thin Profile (0.5 mm) with a Small Base (9.5 mm dia) for Collecting Air Temperature and Velocity Data at Single or Multiple Locations. [ATS]Fig 4 – Here, Air Temperature and Velocity Measurements are Taken Every Second by an eATVS-8 Instrument. stageVIEW Software Provides a Wide Range of Data Collection Choices. [ATS]
Here are some of the ATS instruments available for temperature and velocity measurement and providing the highest-quality thermal reliability test results.
Conclusion
Temperature has a significant effect on reaction rate and the subsequent reliability prediction. Small errors in temperature and airflow measurements can significantly impact reliability predictions. Such errors typically occur in the measurement process or from using inaccurate instruments.
If thermal data is inaccurate, outcomes can include over-designed systems, cost overruns, and products not shipping.
Laboratory-quality thermal instruments can reduce or eliminate measurement and calculation mistakes, leading to higher quality, faster to market and ultimately lower cost products. Just as important, collected data needs to be correctly interpreted. Expert thermal engineers can do just that with data provided or that they obtain themselves.
More information on these topics can be seen at these ATS videos:
How to Properly Measure Air Velocity in Electronic Systems [Link] [3]
How to Perform and Understand Temperature Measurement within Electronic Systems [Link] [4]
Excess heat has affected electronic devices since their earliest days, becoming more critical with the advent of integrated circuits. Today, excess heat impacts the reliability, performance, and lifespan of devices and circuits across all applications. Common impacts of excess heat in electronics are:
Overheating: This can cause sudden shutdowns or failures. Elevated temperatures damage internal components, leading to permanent failure and potential safety risks—especially in high-power systems such as batteries and automotive electronics.
Lower performance: Overheating devices often throttle to reduce heat, and signal integrity may degrade, resulting in reduced performance. Maintaining operation within the designated temperature range lowers electrical resistance and power consumption while improving energy efficiency.
Shorter lifespans: High temperatures cause differential material expansion and deformation, damaging component structures and internal connections.
Thermal issues can also lead to field recalls and warranty claims. Dense PCB layouts may introduce thermal coupling between components, compounding heat-related risks.
Best practice is to engage thermal management specialists early. Effective thermal management controls and dissipates heat to maintain safe operating temperatures. Cooling solutions vary widely, but viable approaches exist for nearly every application.
Applying Professional Thermal Design
Effective cooling solutions require rigorous analysis at the concept stage, development, and testing. The thermal design process includes analytical modeling, experimental validation, and computational simulation across the full packaging domain—components, PCBs, shelves, chassis, and system enclosures.
Figure 1. CFD Simulation of Forced Airflow Across Areas of a Populated PCB.
Robust thermal design leverages both experimental and computational methods, using lab instrumentation and CFD tools such as FloTHERM, CFdesign, and Icepak, among other commercially available tools.
Empirical methods may include airflow or liquid testing, with measurements of velocity, temperature, and pressure, along with thermography using IR or liquid crystal techniques.
A disciplined, methodical approach consistently delivers strong results across diverse cooling challenges. OEMs can often avoid costly redesigns or recalls through expert thermal review, whether on-demand or via ongoing engineering partnerships. Subscription-based thermal services further accelerate validation and integrate thermal considerations earlier in development. More on these below.
Following are examples of carefully applied cooling design methodology.
Dual-Environment Thermal Analysis of a Sealed Offshore Electronics Enclosure
After detailed analytical modeling to envelop the solutions, CFD analysis was performed on a sealed offshore aquaculture enclosure operating in two passive environments: submerged seawater at 30°C and outdoor air at 40°C. The objective was to determine whether passive cooling could maintain component temperatures below 60°C.
Figure 2. (left) Outer Enclosure Temperature Contours. (center) An Internal Aluminum Sled to Transfer Component Heat to the Outer Enclosure. (right) Velocity Vectors Indicate the Slow Motion of the Internal Air.
The analysis showed the passive design was insufficient for the outdoor air case. Key limitations included weak natural convection and poor internal conduction to the enclosure walls. Hot spot spreading resistance significantly contributed to overall temperature rise.
Addressing the air case would also resolve the submerged case. Recommended improvements:
Increase external surface area with fins or a bonded heat sink
Improve internal conduction and reduce interface resistance
Integrate heat pipes or vapor chambers to reduce spreading resistance
Multi-Cold-Plate Liquid Cooling System Design and Optimization
An EV battery manufacturer developed a 4 kW liquid cooling system with four cold plates integrated into a loop including a heat exchanger, DC-DC converter, and onboard charger. The design required balancing thermal performance, manufacturability, and flow distribution.
Figure 3. Four Cold Plates Receive Chilled Coolant from a Heat Exchanger as Part of a Liquid Loop that Included a DC-DC Converter and On-board Charger.
ATS combined analytical modeling with CFD to optimize cold plate geometry and system flow. Key parameters included tube routing, thermal resistance, and pressure drop.
Figure 4. CFD Simulation of a Revised Cold Plate with 10 Tube Passes and 9 Tube Bends.
A 10-pass serpentine tube design maximized heat transfer while maintaining acceptable pressure drop and manufacturability. Additional improvements included optimized tube diameters and balanced manifold routing.
The study demonstrated that effective kilowatt-scale liquid cooling requires coordinated optimization of geometry, pressure drop, and flow distribution. General findings:
Balanced conduction and convection are critical
Targeted passive changes can yield significant gains
CFD-Driven Thermal De-Risking of a Ruggedized Rack System
A baseline-to-optimization CFD study was conducted on a sealed 241 W ruggedized rack system with a 55°C ambient limit. The goal was to identify thermal violations and develop a reliable cooling strategy.
Figure 5. CFD Baseline Model and Surface Temperature Contours of a Ruggedized Rack System.
Through iterative CFD-driven design changes, ATS improved airflow efficiency, heat sink performance, and heat routing. Final modifications included revised heat pipe routing, heat sink replacement, fan reconfiguration, and removal of airflow obstructions. All components achieved thermal compliance.
Figure 6. Surface Temperature Contours of the System’s (left) Original Pin-Fin Heat Sink, and Its Replacement (right) maxiFLOW Heat Sink.
The study showed that sealed systems require holistic optimization across airflow, heat flow routing, fan placement, and heat sink design. General findings:
Analytical modeling identified areas requiring attention and possible solutions
Baseline CFD validated the findings in ‘1’ and identified thermal risks before failure
Heat sink upgrades alone are insufficient without airflow optimization
Final designs improve both compliance and thermal margin
Thermal Optimization of a Passive Aluminum Enclosure
ATS evaluated a sealed passive aluminum enclosure dissipating 75.8 W at 25°C ambient. CFD and parametric analysis identified key thermal constraints and guided optimization.
Figure 7. (left) Distribution of Enclosure Components, (right) Enclosure Baseline Thermal Distribution CFD.
Using 3D CFD with conjugate heat transfer, ATS modeled conduction and natural convection. Results showed that achieving target performance required coordinated improvements across both mechanisms.
Enhancements included improved thermal interface materials, better heat spreading, optimized fin geometry, reduced obstructions, and added vent gaps to enhance natural convection pathways.
Figure 8. The Enclosure Thermal Optimization Included Adding Cross-Cut Venting Gaps to Optimize Natural Convection.
Passive cooling performance is governed by the interaction of internal conduction and external convection. Key limitations included interface resistance and restricted airflow, with diminishing returns from geometry-only changes. Findings:
System-level optimization is more effective than isolated changes
Conclusion
Modern electronics—including AI hardware—generate substantial heat loads, making thermal management a first-order design constraint. Large-scale systems such as data centers incorporate cooling from the outset, but thermal design is equally critical at smaller scales.
Figure 9. ATS Thermal Engineers Use Thermochromic Liquid Crystals to Reveal Hot Spots in Electronic Devices. See a Demonstration Video: https://www.youtube.com/watch?v=peewxRlNVqg
Every application presents unique challenges, and thousands of new devices each year require tailored cooling solutions.
When clients have excess heat issues, ATS engineers work closely with them to deliver cost-optimized, practical thermal and mechanical solutions that align with real-world schedules. The objective is consistent: deliver the right solution the first time.
For OEMs and others with continuing needs for thermal engineering, ATS now provides a subscription service. This comes with tiered support levels, ranging from periodic consultation to embedded engineering support within development teams. Contact ATS for more information on the thermal engineering subscription service.
Figure 10. ATS Thermal Engineering Consulting Tiers Match a Manufacturer’s Ongoing Needs.
To see more details on the above cooling applications, and others, see the Advanced Thermal Solutions, Inc. website, https://www.qats.com/Consulting
Dr. Bahman Tavassoli of Advanced Thermal Solutions, Inc. gives a demonstration of a wind tunnel to Dr. Marc Hodes (left) and a group of students from Tufts University. (Advanced Thermal Solutions, Inc.)
On Friday, Oct. 14, Advanced Thermal Solutions, Inc. (ATS) welcomed Dr. Marc Hodes and a group of six mechanical engineering students from Tufts University to its Norwood, Mass. campus. The students learned about the company, its products, and took a tour of two of ATS’ four laboratories to see some of the testing equipment utilized by ATS engineers.
After a welcome from ATS founder, President and CEO Dr. Kaveh Azar, the students enjoyed a brief introduction from Marketing Director John O’Day about the company, its products, and the importance of thermal management in the design of today’s high-powered electronics.
The lab tours were led by Dr. Bahman Tavassoli, ATS Chief Technologist. First, he took the students into the Characterization Lab to demonstrate the BWT-104 open-loop wind tunnel and the CLWT-067 closed-loop wind tunnel. The students learned how ATS engineers use Candlestick sensors, thermocouples and the iQ-200 to measure air velocity, temperature, and pressure across a PCB using one system. There was also a thermVIEW Liquid Crystal Thermography unit set up, in which ATS engineers use infrared (IR) cameras to examine hot spots on a cold plate.
Students take a closer look at ATS testing equipment. (Advanced Thermal Solutions, Inc.)
Dr. Tavassoli answers questions from Tufts University students. (Advanced Thermal Solutions, Inc.)
The Tufts students learned more than simply how the testing processes worked. They also learned why thermal management is an important consideration in the early stages of a design. Dr. Tavassoli and Dr. Hodes spoke of their professional experiences in the field of thermal engineering and where projects had gone wrong when thermal issues were not considered in the planning stages.
Dr. Azar also joined the students in the lab to show them the wicking material being used by ATS engineers in state-of-the-art vapor chamber designs.
ATS CEO, President and founder Dr. Kaveh Azar speaks with the student from Tufts in the Characterization Lab. (Advanced Thermal Solutions, Inc.)
After the Characterization Lab, the students were taken into the Electronics Lab and were given a demonstration of the Water Flow Visualization equipment. ATS engineers use the equipment to test how air will flow through a system.
The students asked numerous questions of Dr. Tavassoli to get a better idea of the important concepts of thermal engineering that were presented in the 90-minute visit to ATS. Now, the students will have the real-world applications that they saw at ATS in mind when learning the concepts of thermodynamics, thermal fluids, and more in their Tufts courses.
To learn more about Advanced Thermal Solutions, Inc., visit www.qats.com or contact ATS at 781.769.2800 or ats-hq@qats.com.
ATS CEO Dr. Kaveh Azar will deliver a presentation on the thermal management of electric vehicle batteries on Thursday, Sept. 22. (Photo courtesy of Wikimedia Commons)
On Thursday, Sept. 22, Advanced Thermal Solutions, Inc. (ATS), a leading-edge engineering and manufacturing company focused on the thermal management of electronics, will host the New England Section of Society of Automotive Engineers International (SAE NE) for a tour of its Norwood campus and a presentation by ATS founder, President, and CEO Dr. Kaveh Azar.
Dr. Azar’s discussion is entitled, “Battery Thermal Management – The Gateway to the Successful Operation of Electric Vehicles.” He will review the role of temperature in the longevity and performance of nickel metal hydride (NiMH) and lithium-ion electric vehicle batteries; drawing analogies between battery temperature and the junction temperature of modern electronics. As Dr. Azar notes, “Both play an identical role in successful operation of their respective systems.”
There will be a discussion of the analytical methods and design criterion for predicting battery temperature and establishing safe temperature limits. Dr. Azar will present high-level possibilities for thermal management in the electric vehicle sphere as well as cooling options that are deployed for battery thermal management. Current cooling designs can be active or passive. There are forced air, liquid cooling, natural convection and conduction systems used by manufacturers.
Several thermal solutions that engineers have incorporated include increasing the thermal density of the battery, using phase-change material to store transient heat loads and graphite-impregnated paraffin waxes as gap fillers. It is also important for the designs to control temperature distribution across the battery to avoid degradation of cells.
Thermal management is crucial in the design of electric vehicle batteries because temperature has a direct correlation on battery life and performance. It will affect the battery’s ability to store and deliver a charge, weaken polymer- or fiber-based cell dividers, and could potentially lead to thermal runaway.
“The engineers who will design the next hybrid vehicle battery packs will need to be cognizant of the growing need for thermal management,” read a recent article on coolingZONE. “The increased need for thermal protection, due to safety considerations; the reduced thermal capacity, due to lesser mass; and the reduced workable volume are among the challenges to be faced. The hybrid vehicle we may soon drive must have reliable and intelligent cooling systems to cool down their high-density battery packs.”
Why is this topic of particular relevance now?
Electric vehicle sales worldwide have jumped 57 percent from 2015 to 2016, according to data reported by Bloomberg New Energy Finance. The article referenced a Bloomberg report stating that electric vehicle sales could be as much as 47 percent of the automotive market by 2040 (dependent on factors such as oil prices). In the U.S., manufacturers have been urged by President Barack Obama’s EV Everywhere challenge to make electric cars as affordable and convenient as gas-powered vehicles by 2022.
Like cell phone technology in the past two decades, electric vehicles have the potential for widespread usage and to wide-ranging effects inside and outside of the automotive industry. The “digitization of the transport system” will effect, among others, oil companies, car dealerships, maintenance services, and utility suppliers.
“If it is hard to predict when phase change in complex systems begins, it is even harder to predict where it ends,” said Michael Leibreich and Angus McCrone, the authors of the Bloomberg article. “No list of potential impacts of the ‘Transformation of Transportation’ can be complete. However, one thing is for sure: if our predictions for the uptake of electric vehicles are anything like correct, there is no part of the global economy which will not, in some way, be affected.”
Currently, electric vehicles cost an average of $30,000 and travel 100 miles or less on a single charge. Tesla (Model 3) and Chevrolet (Bolt EV) have both promised electric vehicles that will travel 200 miles on a charge within the year. Other car makers, such as Volkswagen and BMW, have announced plans to turn a large portion of their production to electric vehicles in the next few years as well.
While the changes in infrastructure and the length of time that most car owners keep a vehicle (11 years on average) have limited electric vehicle sales to this point, according to Christopher Mims of the Wall Street Journal, the next vehicle that most consumers purchase is likely to be electric.
Mims explained, “It is the nature of disruptive technological shifts that it seems like nothing is changing—until it seems as if everything is changing at once. Electric vehicles have been a long time coming, but they now represent such a clear and present threat to the gasoline engine that Mr. Fox, of the service-station association, now recommends that members signing long-term contracts for fuel include an option to renegotiate if more than 10 percent of a state’s fleet goes electric.”
Electric vehicles offer a smooth drive with better acceleration, less moving parts requiring less maintenance, better air quality, and a better platform for autonomous driving, said Bloomberg. Electric vehicles are the future and that means designing better, longer-lasting, higher-performing batteries will be the future as well.
Cooling those batteries will be critical. As Dr. Azar will explain, without proper thermal management the electric vehicle battery will be inefficient and unable to provide the performance that consumers demand.
Rachel, a 2016 summer intern at Advanced Thermal Solutions, describes the positive learning experience she had at ATS.
Rachel, a 2016 summer marketing intern at Advanced Thermal Solutions (ATS), recently sat down to discuss her experiences with the company, what she learned, and her favorite moments. From search engine optimization to the importance of a strong web presence to utilizing social media in the B2B market, Rachel said that she learned a lot about marketing a company such as ATS.
Among her favorite memories was National Thermal Engineer Day on July 24, which was created by ATS in 2015 to recognize the impact of thermal engineer because without the contributions of thermal engineers, the electronics that are an integral part of today’s life and the cornerstone of this nation’s technological advancement would not be possible.There was a cookout at ATS’ Norwood campus and a lot of fun for the staff, as seen below:
To explore an internship opportunity like Rachel had this summer, contact Advanced Thermal Solutions at ATS-HQ@qats.com.
Hear what Rachel had to say about her time at ATS in the video below:
