Category Archives: Simulation

CFD With Analytical Modeling Gives ATS Edge

In January, Advanced Thermal Solutions, Inc. (ATS) and engineering simulation software leader Future Facilities announced that ATS had purchased multiple seats of 6SigmaET, an electronics thermal simulation software, adding to its CFD (computational fluid dynamics) capabilities.

CFD

ATS engineers are now using 6SigmaET to perform CFD on electronics cooling applications to find optimized thermal solutions for customers. (Advanced Thermal Solutions, Inc.)

In a joint press release from the two companies, ATS founder and CEO Dr. Kaveh Azar said, “We have decades of experience with a broad base of commercially available CFD tools. For the electronics thermal management analyses, 6SigmaET showed excellent agreement with our empirical and analytical modelling.

He added, “We were equally impressed with its ease of use and a short learning curve. Our engineering team was able to apply the tool to different levels of simulation extending from component to system level modelling. The speed of convergence and ease of use of 6SigmaET, have made it the first CFD software to use.”

6SigmaET becomes the lead thermal simulation software for ATS engineers dealing with standard electronics cooling challenges. ATS engineers will be able to quickly and efficiently simulate junction and ambient temperatures across boards and components or define airflow to find fan operating points or get a better understanding of pressure drop in a system.

Dr. Azar continued, “We always want to be working with the best breed of tools to deliver the innovative, high-quality and cost-effective thermal management and packaging solutions our customers expect. As a result, this addition is good news for our customers. The rich features of the 6SigmaET thermal simulation package not only enable us to do more when it comes to simulation, but also allows us to further deliver the solution to our clients in a shorter time interval. It is my highest compliment to 6SigmaET development team for putting together such a robust and effective software.”

Adding 6SigmaET to ATS CFD capabilities, which also includes FloTHERM from Mentor and Autodesk CFD (formerly CFdesign), enables engineers to save customers time in the design phase and makes it easier for ATS engineers to devise optimal thermal solutions.

ATS engineer Anatoly Pikovsky said, “Visual is definitely a great thing to have. If you look at this temperature map, for instance, you can look at the defined map and say right away, okay I have a very high temperature right in the middle.”

Pikovsky, who was working on Autodesk CFD to design a customized cold plate for a customer, demonstrated how the software allows for him to analyze the pattern of fluid flow through complex geometries that were imported from SolidWorks drawings. He used the software to show hot spots and fluid velocity and how small changes, such as the number of fins within the cold plate, could alter the results.

Field Application Engineer Vineet Barot explained that he used 6SigmaET on a board in which there was pressure drop coming from vents at the end of the board. In simulations, he was able to add fins to the heat sink without altering the fan operating point and quickly provide a thermal solution that was presented to a customer. He said, “If you had a standard 1-U chassis you can build it from scratch and run it in half an hour.”

While CFD continues to evolve to handle more complex problems, while also becoming easier to use for engineers, simulations are only part of the solution.

ATS engineers also perform analytical modeling, literally putting pen to paper with basic thermodynamic equations, to define the problem and provide a reference point for simulations. Coupling analytical and computer modeling is what sets ATS apart from its competitors because it ensures that thermal solutions provided by CFD are correct.

“CFD will give you a solution, whether it’s right or wrong, it will give you a solution,” Pikovsky said. “That’s the way it’s designed. Analytical coupled with CFD gives you a good reference point to know whether you’re in the ballpark.”

Analytical modeling also speeds up the process of finding an optimized solution. Rather than spending days or weeks plugging in different fin numbers and heights or trying numerous heat sink geometries, ATS engineers can define a small range of iterations, limiting the variables for CFD, to avoid countless simulations, each of which could take hours to run.

Pikovsky said, “Maybe you’ve designed a heat sink for certain airflow and you want to determine the number of fins. You can do it with CFD, but you start varying fins and it’s going to take you days. Analytical is great because you can determine the optimal number of fins and start CFD with that.”

CFD is a critical component of ATS thermal consulting and design services. 6SigmaET has quickly been adopted by ATS engineers as the lead software and been used in the design of thermal solutions for a number of customers in the past few months.

But, it is the combination of CFD with ATS engineers’ emphasis on analytical modeling that has made ATS a leader in the thermal management of electronics.

For more information about Advanced Thermal Solutions, Inc. (ATS) thermal management consulting and design services, visit https://www.qats.com/consulting or contact ATS at 781.769.2800 or ats-hq@qats.com.

Analysis of Fan Curves and Fan Laws in Thermal Management of Electronics

This is the second installment in a two-part series examining the use of fans in the thermal management of electronics. Part one, which can be found at https://www.qats.com/cms/2017/03/06/utilizing-fans-thermal-management-electronics-systems, took a closer look at the common types of fans and blowers and the factors that engineers should consider when picking a fan.

In part two, basic fan laws will be explored, as well as using fan curves to analyze fan performance in a system. These standard calculations can help engineers establish boundary conditions for air velocity and pressure drop and ensure that these will meet the thermal requirements (e.g. ambient and junction temperature) of the system.

Fan Laws

CFD simulations of air velocity in a system with fans drawing air across high-powered components. Utilizing fan curves and fan laws enabled ATS engineers to establish the parameters for a successful use of fans for cooling this system. (Advanced Thermal Solutions, Inc.)

FAN LAWS

As noted by Mike Turner of Comair Rotron in “All You Need to Know About Fans,” the primary principle for determining whether or not a fan work within a particular system is that “any given fan can only deliver one flow at one pressure in a particular system.” Each fan has a specific operating point that can be discovered on the fan curve at the intersection of fan static pressure curve and the system pressure curve. Turner advises, “It is best to select a fan that will give an operating point being toward the high flow, low pressure end of the performance curve to maintain propeller efficiency and to avoid propeller stall.”

Before getting to the fan curve though, engineers must run through basic calculations to understand the conditions of the systems in which the fans will be placed. The three basic fan laws, according to Eldridge USA, are as follows:

Fan Laws

While those fan laws will tell you about the specific fans, it is also critical to examine the system in which the fans will be operating. Among the equations that can be used to characterize a system are Volumetric Flow Rate, Mass Flow Rate, Pressure, Power, and Sound (equations are listed below).

Fan Laws

A Qpedia Thermal eMagazine article entitled, “How to Use Fan Curves and Laws in Thermal Design,” added:

“Published fan laws apply to applications where a fan’s air flow rate and pressure are independent of the Reynolds number. In some applications, however, fan performance is not independent and thus the change in Reynolds number should be incorporated into the equation. To determine if the Reynolds number needs to be considered, it must first be calculated.

“According to AMCA specifications, an axial fan’s minimum Reynolds number is 2.0×106. When the calculated Reynolds number is above this value, its effects can be ignored.”

The equation to calculate the Reynolds number is as follows:

Fan Law

In an “Engineering Letter” from The New York Blower Company, it was explained that fan laws only work “within a fixed system with no change in the aerodynamics or airflow characteristics of the system.” In the case of electronics cooling, in which the system requirements will be mostly consistent (with margins for error in case of max power usage), these laws will govern the capabilities of the fans to provide the necessary forced convection cooling for the components in the system.

The Engineering Letter continued, “During the process of system design, the fan laws can be helpful in determining the alternate performance criteria or in developing a maximum/minimum range.” A Qpedia article entitled, “Designing Efficient Fans for Electronics Cooling Applications,” added, “As a general rule, fan efficiency increases with blade diameter and rotational speed.”

There are tools that can assist engineers in the calculation of these basic fan laws, including fan calculators, such as the one provided by Twin City Fans & Blowers.

ANALYZING FAN CURVES AND FAN PERFORMANCE

The aerodynamics of a fan can be charted in a fan curve, which displays the static pressure of the system dependent on the amount of air flow. As Turner noted, fan curves are read from right to left, beginning “with healthy aerodynamic flow and follow it through to aerodynamic stall.” Turner continued, “It is best to select a fan that will give an operating point being toward the high flow, low pressure end of the performance curve to maintain propeller efficiency and to avoid propeller stall.”

Fan Laws

An example of a basic fan curve with static pressure on the Y-axis and airflow on the X-axis. Fan curves are read from right to left beginning with healthy airflow.

There are means for testing fan curves, such as the FCM-100 Fan Characterization Module (pictured below) from Advanced Thermal Solutions, Inc. (ATS). The FCM-100 is specially designed with flow restriction plates that allow the user to control pressure drop across the system during testing. Used in conjunction with pressure and velocity measurement equipment, it verifies manufacturer performance data.

Fan Laws

The ATS FCM-100 Fan Characterization Module is a specialized unit designed to test and characterize fans of various sizes and performance outputs. (Advanced Thermal Solutions, Inc.)

The Qpedia article on fan curves explained, “During a typical fan test, a dozen or more operating points are plotted for pressure and flow rate, and from this data a fan curve is constructed.”

Once a fan curve is determined, it is possible to examine the data and find the operating range for the fans that will meet the thermal requirements of a system. It is also important to note a section in the fan curve, often referred to as the knee of the curve in which the relationship between flow rate and static pressure is no longer easy to predict. There is no longer an easily recognizable, calculable relationship between how a change in one will affect the other.

ATS field application engineer Vineet Barot explained how he analyzed fan curve data, particularly the knee of the curve, in a recent project:

“This is flow rate versus pressure. The more pressure you have in front of a fan, the slower it can pump out the air and this is the curve that determines that.

Fan Laws

Fan operating points on the board, determined by CFD simulations. (Advanced Thermal Solutions, Inc.)

“This little area here is sometime called the knee of the fan curve. Let’s say we’re in this area, the flow rate and pressure is relatively linear, so if I increase my pressure, if I put my hand in front of the fan, the flow rate goes down. If I have no pressure, I have my maximum flow rate. If I increase my pressure then the flow rate goes down. What happens in this part? The same thing. In the knee, a slight increase in pressure, so from .59 to .63, reduces the flow rate quite a bit.

Stratix 10 FPGA

CFD simulations showed that the fans were operating in the “knee” where it is hard to judge the impact of pressure changes on flow rate and vice versa. (Advanced Thermal Solutions, Inc.)

“So, for a 0.1 difference in flow rate (in cubic meters per second) it took 0.4 inches of water pressure difference, whereas here for a 0.1 difference in flow rate it only took a .04 increase in pressure. That’s why there’s a circle there. It’s a danger area because if you’re in that range it gets harder to predict what the flow will be because any pressure-change, any dust build-up, any change in estimated open area might change your flow rate.

Fan Laws

CFD analysis of flow vectors across high-powered components on a PCB. This simulation was part of an examination of fan performance in a system. (Advanced Thermal Solutions, Inc.)

CONCLUSION

While it is important to know the types of fans on the market and manufacturers provide data about the power and operating ranges of each product, it is important for there to be a basic understanding of the laws that govern how fans operate in a system and an ability to examine fan curve data in order to optimize performance.

“Bulk testing of electronics chassis provides the relationship between air flow and pressure drop and determines the fan performance needed to cool a given power load. The fan rating is often a misunderstood issue and published ratings can be somewhat misleading. Knowledge of fan performance curves, and how they are obtained, allows for a more informed decision when selecting a fan. Continued and ever shortening product design cycles demand a ‘get it right the first time’ approach. The upfront use of system curves, fan curves and fan laws can help meet this goal.”

Read more and see examples of fan laws and curves in practice at https://www.qats.com/cms/2013/07/24/how-to-use-fan-curves-and-laws-in-thermal-design.

CLICK HERE FOR PART I

To learn more about Advanced Thermal Solutions, Inc. consulting services, visit www.qats.com or contact ATS at 781.769.2800 or ats-hq@qats.com.

Discussion of Thermal Solution for Stratix 10 FPGA

An Advanced Thermal Solutions, Inc. (ATS) client was planning on upgrading an existing board by adding Altera’s high-powered Stratix 10 FPGAs, with estimates of as many as 90 watts of power being dissipated by two of the components and 40 watts from a third. The client was using ATS heat sinks on the original iteration of the board and wanted ATS to test whether or not the same heat sinks would work with higher power demands.

In the end, the original heat sinks proved to be effective and lowered the case temperature below the required maximum. Through a combination of analytical modeling and CFD simulations, ATS was able to demonstrate that the heat sinks would be able to cool the new, more powerful components.

ATS Field Application Engineer Vineet Barot recently spoke with Marketing Director John O’Day and Marketing Communications Specialist Josh Perry about the process he undertook to meet the requirements of the client and to test the heat sinks under these new conditions.

JP: Thanks again for sitting down with us to talk about the project Vineet. What was the challenge that this client presented to us?
VB: They had a previous-generation PCB on which they were using ATS heat sinks, ATS 1634-C2-R1, and they wanted to know if they switched to the next-gen design with three Altera Stratix 10 FPGAs, two of them being relatively high-powered, could they still use the same heat sinks?

Stratix 10 FPGA

The board that was given to ATS engineers to determine whether the original ATS heat sinks would be effective with new, high-powered Stratix 10 FPGA from Altera. (Advanced Thermal Solutions, Inc.)

They don’t even know what the power of the FPGAs is exactly, but they gave us these parameters: 40°C ambient with the junction temperatures to be no more than 100°C. Even though the initial package is capable of going higher, they wanted this limit. That translates to a 90°C case temperature. You have the silicon chip, the actual component with the gates and everything, and you have a package that puts all that together and there’s typically a thermal path that it follows to the lid that has either metal or plastic. So, there’s some amount of temperature lost from the junction to the case.

The resistance is constant so you know for any given power what the max will be. The power that they wanted for FPGAs 1 and 2, which are down at the bottom, was 90 watts, again this is an estimate, and the third one was 40 watts.

JP: How did you get started working towards a solution?
VB: Immediately we tried to identify the worst-case scenario. Overall the board lay-out is pretty well done because you have nice, linear flow. The fans are relatively powerful, lots of good flow going through there. It’s a well-designed board and they wanted to know what we could do with it.

I said, let’s start with the heat sinks that you’re already using, which are the 1634s, and then go from there. Here are the fan specs. They wanted to use the most powerful fan here in this top curve here. This is flow rate versus pressure. The more pressure you have in front of a fan, the slower it can pump out the air and this is the curve that determines that.

Stratix 10 FPGA

Fan operating points on the board, determined by CFD simulations. (Advanced Thermal Solutions, Inc.)

This little area here is sometime called the knee of the fan curve. Let’s say we’re in this area, the flow rate and pressure is relatively linear, so if I increase my pressure, if I put my hand in front of the fan, the flow rate goes down. If I have no pressure, I have my maximum flow rate. If I increase my pressure then the flow rate goes down. What happens in this part, the same thing. In the knee, a slight increase in pressure, so from .59 to .63, reduces the flow rate quite a bit.

Stratix 10 FPGA

CFD simulations showed that the fans were operating in the “knee” where it is hard to judge the impact of pressure changes on flow rate and vice versa. (Advanced Thermal Solutions, Inc.)

So, for a 0.1 difference in flow rate (in cubic meters per second) it took 0.4 inches of water pressure difference, whereas here for a 0.1 difference in flow rate it only took a .04 increase in pressure. That’s why there’s a circle there. It’s a danger area because if you’re in that range it gets harder to predict what the flow will be because any pressure-change, any dust build-up, any change in estimated open area might change your flow rate.

The 1634 is what they were using previously. It’s a copper heat pipe, straight-fin, mounted with a hardware kit and a backing plate that they have. It’s a custom heat sink that we made for them and actually the next –gen, C2-R1, we also made for them for the previous-gen of their board, they originally wanted us to add heat pipes to this copper heat sink, but I took the latest version and said, let’s see what this one will do. For the third heat sink, I went and did some analytical modeling to see what kind of requirement would be needed and I chose one of our off-the-shelf pushPIN™ heat sinks to work because it was 40 watts.

JO: Is the push pin heat sink down flow from the 1634, so it’s getting preheated air?
VB: Yes. This is a pull system, so the air is going out towards the fans.

Stratix 10 FPGA

CFD simulations done with FloTherm, which uses a recto-linear grid. (Advanced Thermal Solutions, Inc.)

This is the CFD modeling that ATS thermal engineer Sridevi Iyengar did in FloTherm. This is a big board. There are a lot of different nodes, a lot of different cells and FloTherm uses recto-linear grids to avoid waviness. You can change the shape of the lines depending on where you need to be. Sri’s also really good at modeling. She was able to turn it around in a day.

Stratix 10 FPGA

Flow vectors at the cut plane, as determined by CFD simulations. (Advanced Thermal Solutions, Inc.)

These are the different fans and she pointed out what the different fan operating curves. Within this curve, she’s able to point out where the different fans are and she’s pointing out that fan 5 is operating around the knee. If you look at all the different fans they all operate around this are, which is not the best area to operate around. You want to operate down here so that you have a lot of flow. If you look at the case temperatures, remember the max was 90°C, we’re at 75°C. We’re 15°C below, 15° margin of error. This was a push pin heat sink on this one up here and 1634s on the high-powered FPGAs down here.

Stratix 10 FPGA

JP: Was there more analysis that you did before deciding the original heat sinks were the solution?
VB: I calculated analytical models using the flow and the fan operating curves from CFD because it’s relatively hard to predict what the flow is going to be. Using that flow and doing a thermal analysis using HSM (heat sink modeling tool), we were within five percent. What Sri simulated with FloTherm was if a copper heat sink with the heat pipe was working super well, let’s try copper without the heat pipe and you can see the temperature increased from 74° to 76°C here, still way under the case temperature. Aluminum with the heat pipe was 77°; aluminum without the heat pipe was 81°, so you’re still under.

Basically there were enough margins for error, so you could go to smaller fans because there’s some concern about operating in the knee region, or you can downgrade the heat sink if the customer wanted. We presented this and they were very happy with the results. They weren’t super worried about operating in the knee region because there’s going to be some other things that might shift the curve a little bit and they didn’t want to downgrade the heat sink because of the power being dissipated.

Stratix 10 FPGA

Final case temperatures determined by CFD simulations and backed up by analytical modeling. (Advanced Thermal Solutions, Inc.)

JO: What were some of the challenges in this design work that surprised you?
VB: The biggest challenges were translating their board into a board that’s workable for CFD. It’s tricky to simplify it without really removing all of the details. We had to decide what are the details that are important that we need to simulate. The single board computer and power supply, this relatively complex looking piece here with the heat sink, and we simplified that into one dummy heat sink to sort of see if it’s going to get too hot. It all comes with it, so we didn’t have to work on it.

The power supply is even harder, so I didn’t put it in there because I didn’t know what power it would be, didn’t know how hot it would be. I put a dummy component in there to make sure it doesn’t affect the air flow too much but that it does have some effect so you can see the pressure drop from it but thermally it’s not going to affect anything.

JO: It really shows that we know how to cool Stratix FPGAs from Altera, we have clear solutions for that both custom and off-the-shelf and that we understand how to model them in two different ways. We can model them with CFD and analytical modeling. We have pretty much a full complement of capabilities when dealing with this technology.

JP: Are there times when we want to create a TLB (thermal load board) or prototype and test this in a wind tunnel or in our lab?
VB: For the most part, customers will do that part themselves. They have the capability, they have the rack and if it’s a thing where they have the fans built into the rack then they can just test it. On a single individual heat sink basis, it’s not necessary because CFD and analytical modeling are so established. You want two independent solutions to make sure you’re in the right ballpark but it’s not something you’re too concerned that the result will be too far off of the theoretical. For another client, for example, we had to make load boards, but even then they did all the testing.

To learn more about Advanced Thermal Solutions, Inc. consulting services, visit https://www.qats.com/consulting or contact ATS at 781.769.2800 or ats-hq@qats.com.

Q&A: ATS Thermal Engineer Sridevi Iyengar

Sridevi Iyengar

ATS thermal and field application engineer Sridevi Iyengar does CFD modeling (like the one shown above) and on-site consulting for ATS from her location near Bangalore, India. (Advanced Thermal Solutions, Inc.)

Advanced Thermal Solutions, Inc. field application and thermal engineer Sridevi Iyengar recently spoke with Marketing Communications Specialist Josh Perry about her career in engineering and the work that she does for ATS. Iyengar works near her home in Bangalore, India and provides ATS with CFD simulations and on-site support for customers in the region.

In this Q&A, Iyengar speaks about why she became an engineer in the first place, how she came to work at ATS, the type of projects that she works on, the challenges that she faces as a woman in a male-dominated industry, and what it is like working halfway around the world from the engineers at ATS’ Norwood, Mass. campus.

JP: How did you get interested in engineering? How did it all start for you?
SI: I was a good student in high school and in college and my father is a metallurgical engineer. He was a professor in one of the premier institutes in India, the Indian Institute of Science. When we were at the crossroad, during 12th grade, honestly the bright students either went into medicine or engineering and since my math skills were pretty good and I’d been to the Indian Institute of Science a couple of times I had written the entrance examinations for both streams. For engineering, I got into a very good school.

Although I didn’t know about the different disciplines of engineering, I happened to go into chemical engineering because that’s what my rank got me into. I liked it because chemical is kind of a fusion between math and physical phenomena and so that’s where my engineering journey started.

After my Bachelor’s, I wanted to do higher studies. I got married and came to the United States and I wanted to continue in my field of study. I didn’t want to move into software like pretty much everybody else from India when they move to the U.S. I wanted to keep myself different and I had a lot of support for that from my family. The first place I set up home is Norwood, Mass. (in 1993). I was preparing for my GRE and contemplating whether I should take my AGRE but I got positive responses from a couple of schools that I was also keen on getting into. I had options. One was the University of Massachusetts – Lowell, one was Rutgers University and the University of California – San Diego. I chose San Diego.

I was actually accepted into the doctoral program, however at UC-San Diego I liked the fluid mechanics and heat transfer program but then I didn’t want to jump into a Ph. D. without really having real world experience. I wanted to finish my Master’s, work for a few years and then maybe come back if I was interested. Much to my disappointment of my dad, I dropped out of the doctorate program with my Master’s and entered the job scene.

My entry into thermal engineering was kind of by chance. My first job was with Structural Dynamics Research Corporation (SDRC) in San Diego. It was the advanced test and analysis group. I had a background in heat transfer and fluid mechanics and therefore I joined as an intern and they made me do a little bit of this and that. The software associated with the IDEAS master series for electronics cooling was MAYA-ESC electro-systems cooling and TMG (thermal model generator) and we did a project for Cisco Systems in the Bay Area. I worked for about a year and half at ATA-SDRC. SDRC was doing a lot of projects for defense and their core area was becoming more and more defense and I was not a U.S. citizen so it was very difficult for them to assign me to projects because I didn’t have security clearance. At that time I jumped ship and I joined Cisco Systems as a mechanical engineer.

JP: How did you hear about Advanced Thermal Solutions, Inc.? How did you end up working here?
SI: ATS, the company, I knew even when I was at Cisco back in 1999. I was with Cisco until 2005 and at that time I knew about Advanced Thermal Solutions because as a mechanical engineer my job was also to source heat sinks. Also, that it was based in Norwood kind of struck a chord and it remained in my mind. I had known a lot about [ATS CEO, President and founder] Dr. Kaveh Azar because a close colleague of mine had worked closely with Kaveh. And of course Qpedia Thermal eMagazine was/is a very useful online journal.

How I joined ATS was a very, very chance meeting. We moved back to India in 2009 and I was working for an aluminum extrusion company in their thermal management division. It’s a Swedish company called Sapa. Sapa opened an office in India and it was just the sales manager and myself in the Indian team when I started. I worked with Sapa for three years and I was working for their global application team, half working for Sweden and half trying to set up the market in India. At Sapa I did a little bit more than thermal management. Sapa acquired an extrusion facility and also had a machining/anodizing unit. I was exposed to various aspects of manufacturing with regards to aluminium extrusions, fabrication etc., and worked on several other projects, which needed someone who could work with the customers and the manufacturing team at Sapa – sort of like a liaison and the engineering hand of the sales person.

When I quit Sapa, I thought I would go freelance doing electronics cooling consulting and I met one of the sales channel partners for ATS and with him I went and met Dr. Kaveh and Shashwat Shashwat (ATS Product Realization Manager), who were visiting India. This was in May of 2014 and initially it was just supposed to be a ‘hello, how are you’ meeting, but then we started talking and having common professional contacts and interests made it a very interesting interaction. We had lunch and when I came back home that evening Shashwat called me and asked if I was interested in working for ATS. I had no doubts whether I would take this opportunity; I took it with both hands. It’s worked out very well for me so far.

JP: What kinds of projects are you working on for ATS?
SI: There were two things for me, the mandate. One was that we wanted to beef up our presence in India. We already had a sales presence and we were selling heat sinks through Digi-Key and if the engineers know what they want then it’s not a big deal, but it helps them so much to know that there is technical staff from ATS present in India and in Bangalore in the southern region. They call and they say, ‘We’re looking at this heat sink, do you think it’s okay?’ Otherwise they send an email and then they wait for Norwood to reply. So, my role was to support the local sales partners that we have. They do the initial sales call and everything, but then if there’s anything technical they can say, ‘You know, ATS has a presence here? We have this engineer who is in electronic cooling and she has experience.’ I’ve gone to several meetings with them.

Secondly, for the U.S. customers, when it comes to CFD simulations like FloTherm then I work very closely with Norwood. In fact, I’ve done quite a few projects with [ATS field application engineers] Greg Wong or Peter [Konstalilakis], Vineet [Barot] too. A lot of times there are CFD simulations, they face the customers, they get the answers and I run the simulation and build the models here, do the analysis, we discuss the results and they send it to the customer.

JP: Is there a lot of collaboration between yourself and the engineers here in Norwood?
SI: Almost daily. I am online pretty much every day from 6 and on Wednesdays and Fridays we have the team meeting. On other days, I usually chat up with my counterpart on the project and, if it’s a major project, then the discussion is fairly involved. A lot of times, I’ll have a lot of questions so I’ll contact my teammates during my evening and he’ll take it up with the customer, get all the questions answered and by the time morning rolls around everything is sent to me by email and I get through my day. There is a lot of collaboration.

JP: Looking at thermal engineering as a whole, where do you see the industry going?
SI: People realize the importance of up-front thermal design and these folks who are dealing with high-powered components are aware of the importance of up-front thermal design. However there are still a lot of projects in which the hardware engineers are still not zoned into thinking of up-front thermal management, it’s coming in as kind of a ‘Oh it’s too hot, let’s do something about it’ approach. However, I think that mindset is changing a lot and I think the next-gen heat sinks like vapor chambers, heat pipes, and nano-materials will really start making their appearance more and more in thermal solutions because we’re getting to a point where the run of the mill is not cutting it.

JP: Do you see that change coming fairly quickly? In this industry, it seems like things change every day.
SI: The mindset should change because there’s always an aversion towards liquid and PCB. The more we educate people and the fact that we see everything in liquid cooling systems working…It takes some time for them to know that, okay it is a fairly fail-safe method. It will take at least a year or two and it should be running at that time and then people will catch on. It’s not something that can be easily brought on, I think, because generally we know that liquids and electronic components don’t mix. To assure them that it will not mix and there’s no chance of it coming into contact, I think that’s the stumbling block.

It’s market education and also having systems out there functioning, so that we can show them it’s not just theoretical. You have systems in practice and I think that makes a difference. If we can show it in theory, it doesn’t help as much because in theory everything looks wonderful, so we need to show them in practice and all the possible problems that can come up have been addressed and it is working in the field not just in the test lab.

JP: As a woman in a predominantly male-dominated industry, has it been difficult at all?
SI: In India, even back in 1993, we had a lot of engineers who were graduating but a lot of them didn’t stay back in what I call hardcore engineering. People used to go into information technology because they thought somehow it was more suitable for the women in the workforce situation. But I personally, I’ve had a fulfilling time and it is good to distinguish yourself and be different. The work that we do at ATS is hardcore engineering and we have engineers to lead us. We have Dr. Kaveh Azar and Dr. Bahman Tavassoli who have years of engineering experience and yeah sometimes they come down hard on us but that’s because they know what they’re doing. They’ve been there, done that, and they want to extract the best out of you and they want you to think like an engineer always. That’s what is unique of working at ATS.

JP: Do you hope to inspire other women to not only join the field, but stick with the ‘hardcore’ engineering?
SI: Yeah, absolutely. There have been young women who have reached out to me, young engineers who graduated in India, and I tell them have patience and learn the skills needed to get a job. It’s very easy to learn a few programming languages and jump into IT, especially in India right now, but you’re going to be just like anybody else. If your heart really lies in engineering, you should stick on, network, upgrade your skills and you’ll definitely find a job. The first job is everything you need and after that, if you do well there, then the path is smooth.

JP: How has it been for you as a ‘distant worker’ in terms of not being located here in Norwood? We have a lot of great technology like Skype and GoToMeeting, how have you found it being a ‘distant worker’?
SI: Since I interact with the engineers on an almost daily basis it is not that different. ATS engineers and the customers are very understanding of the time difference and accommodate the meetings, if any, so that it is not totally at unearthly hours for me. I also have the freedom to have my own schedule and that is very helpful since I am a working mother. I’ve been to ATS once and so I have met most of the team there.

The only thing is that I don’t have that touch and feel. Sometimes the ATS engineers have the heat sinks/components on their desk and they’re looking at it. A lot of times they will look at it, turn it around and these are things that I will have to accomplish through video call on Skype or the engineers take pictures and send them to me. But it’s not the same. That’s the only drawback. And of course when you folks have your team lunches/picnics … I feel left out.

JP: From our conversation, it sounds like you really like challenging projects?
SI: I think we all like to be challenged once in a while. With involved models, one of the challenges was I’d have to remotely log in and run the model in the 12-core PC and ensure nobody is logged in and I used to run it through the night and post-process it via remote connection. I’d transfer the results over and make the PowerPoint. However I was given a super fast simulation computer locally so all I need is a VPN connection. Even if the VPN connection goes down, FloTherm will not cut off the simulation and it runs through the solve.

Every now and then I support local customers with their heat sink selection requests. Some local customers have asked for training sessions as well, which is something I would like to start fairly soon.

To learn more about Advanced Thermal Solutions, Inc., visit www.qats.com or contact ATS at 781.769.2800 or ats-hq@qats.com.

What Cost Reduction Strategies Make New Product Introductions Faster?

Getting to markets faster and in the most cost-effective way is the primary goal of today’s product development process. Choosing a thermal design engineering partner that understands that goal makes a company’s product realization process simpler and faster. There are number of strategies a company’s project engineers can use to save time and money in the design of an electronics cooling solution. Two of the most efficient methods are Virtual Engineering Demos (VED) and Thermal Load Boards (TLB).

VEDs make it possible for project engineers to remotely see an instrument, how it operates, ask questions about how it works, and, if the project is included in the demo, get data in real time about a design. In this method, a live demo is setup at a thermal design engineering partner’s laboratory. Whether the project is a PCB, a system, or another product type, it can be included in the VED and be run through the lab set-up.

Greg Wong

ATS engineer Greg Wong gives a live, online demonstration from the ATS research lab to a potential customer. (John O’Day/Advanced Thermal Solutions, Inc.)

Candlestick Sensor

ATS engineer Greg Wong sets up to demonstrate the ATVS-2020, Candlestick Sensors and StageVIEW Data Acquisition Software (DAQ) for measuring and analyzing temperature for an electronics board in this VED. (Advanced Thermal Solutions, Inc.)

VED in Lab

Equipment setup and live camera feeds are all part of a VED setup. (Advanced Thermal Solutions, Inc.)

As the project is analyzed, data is shown on the engineering partner’s computer screen, which is in turn broadcast in real time to the project engineers via a live video feed. The video feed simultaneously shows the demo and the software’s operation, while allowing bi-directional conversation between the engineering partner and the project engineers in one or more locations.

stageVIEW_software

Screenshot showing data being recorded in stageVIEW. This information is available to the remote team. (Advanced Thermal Solutions, Inc.)

The advantages of this strategy to project engineers are:

• Quick evaluation of a design to determine if there is a need for new equipment in a project.
• No lag time in talking with a thermal design engineering partner about how to approach the thermal measurement of project
• Reducing the need to travel to a thermal design engineering partner’s lab.
• Faster response on lab testing, shortening the design cycle.

A Thermal Load Board (TLB) is another strategy for reducing the cost of a design, while getting a product to market faster. TLBs are created by a thermal engineering partner using a simple one- or two- layer non-populated PCB, heat sinks, thermally equivalent mock semiconductors and other mock components created with a 3-D printer.

TLB 3-D printing

Using these components a populated board is created that allows the testing of the heat sinks chosen for the project work and measurement of the airflow over the components and through the board. (Advanced Thermal Solutions, Inc.)

The thermal engineering partner is effectively creating a mock version of the functional board. The design of the TLB is based on the size and placement of the semiconductors and other components on the actual board, which is provided by the project engineers, and provides a cheaper and quicker means of producing a prototype for testing. The data from that testing will in turn expedite the design process and time to market.

This can be a very cost-effective method for doing heat sink characterization for the following reasons:

It reduces electronic system development cost.
o A system developer can focus on thermal issues very quickly instead of waiting for an expensive prototype to come out of the factory.
o Rather than using a potentially expensive project, testing on prototypes can determine design flaws without requiring a significant
cost.
o Because prototypes are less expensive, each iteration of a design can quickly go through an initial series of tests.
It reduces time to market.
o Valuable resources can be applied to engineering the best solution because a load board can generally be created in 1-2 weeks and at a
fraction of the cost of a full PCB.
It allows a physical testing very early in the design.
o Many times components on a PCB will obstruct air flow, requiring either costly design changes during NPI (new product introduction) or
requiring engineers to over-design a board and the thermal management solution, putting the product outside its cost objective.

After a thermal load board is created, the board is ready to be used:

Completed Load Board

A completed load board ready for testing. (Advanced Thermal Solutions, Inc.)

The heaters on the board can be powered up to dissipate the same level of power as the semiconductors they are meant to represent. Heat sinks can then be applied based on initial analysis done via integral modeling, mathematical modeling or through CFD (computational fluid dynamics). To test just air flow, heat sinks can even be created by 3-D printing.

Once populated with heat sinks, the board can be tested in a wind tunnel to see if the air flow will be sufficient. Wind tunnel testing methods include smoke flow visualization or water tunnel testing in order to examine air flow and ensure the most functional and cost-effective design is applied.

Getting to market faster and with the best possible design is very important in today’s product development process. Working with a thermal engineering partner, such as Advanced Thermal Solutions, Inc. (ATS), that offers Virtual Engineering Demos (VED) and Thermal Load Boards (TLB) will benefit a project’s bottom line and ensure a project’s successful completion. Project engineers will know that their design has proper thermal management early in the process, meaning that they will not have to over-design the project, which will save time and money in the long run.

Learn more about ATS and its capabilities as a thermal engineering partner for your next project by visiting www.qats.com or by calling 781-769-2800.

References:

Thermal Load Board Design Considerations


http://www.3dsystems.com/learning-center/case-studies/lowering-cost-and-reducing-production-time-projet-3d-printing-lets