<div dir="ltr"><div dir="ltr">Actually, it looks like Joule-Thompson cooling to me (Especially given the "Joule Force" name). You've got the air intake (ambient), then an expansion nozzle, into a low-pressure region, which is created by the fan at the end. So the outlet velocity of the air (and thus it's kinetic energy) is higher than the inlet velocity, which would lower the internal energy, and thus the temperature. Instead the fins/nozzle/heatsink transfer heat to the expanding gas, which exits a little above ambient temperature. I imagine the drawback is you really need to get rid of that high velocity hot air, and can't recirculate it, or the kinetic energy would be converted back to thermal energy, and mess it all up. The descriptions do all involve the exhaust air being ducted to the outside. This article has the most technical detail: <a href="https://www.nextplatform.com/2018/12/04/the-leading-edge-of-air-cooled-servers-leads-to-the-edge/">https://www.nextplatform.com/2018/12/04/the-leading-edge-of-air-cooled-servers-leads-to-the-edge/</a></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Jan 25, 2019 at 11:33 AM Prentice Bisbal via Beowulf <<a href="mailto:beowulf@beowulf.org">beowulf@beowulf.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<p>You all know how much I like talking about heat transfer and
server cooling, so I decided to do some research on this product:</p>
<p>Here's their website: <br>
</p>
<p><a class="gmail-m_8157281066646160146moz-txt-link-freetext" href="https://forcedphysics.com" target="_blank">https://forcedphysics.com</a><br>
</p>
<p>and here's their YouTube channel with 5 videos:<br>
</p>
<p><a class="gmail-m_8157281066646160146moz-txt-link-freetext" href="https://www.youtube.com/channel/UClwWeahYGuNl0THWVz1Hyow/videos" target="_blank">https://www.youtube.com/channel/UClwWeahYGuNl0THWVz1Hyow/videos</a> </p>
<p>This is really nothing more than an air-cooled heatsink. I'm
afraid I'm going to have to call BS on this technology for the
following reasons: <br>
</p>
<p>1. It still uses air as the primary cooling medium. I just don't
think air has adequate thermal conductivity or thermal capacity to
serve modern processor, no matter what you do to it. <br>
</p>
<p>2. In the videos, they present highly idealized tests with no
control to use for comparison. How do I know I wouldn't get the
same results doing the same experiment but using a similar duct
fashioned out of sheet metal. <br>
</p>
<p>3. Using this technology means a complete redesign of your server
hardware and possibly your racks.</p>
<p>4. None of the information in the videos or on their website
really explains how this technology works, and what really
differentiates it from any other air-cooled heat sink. Most people
with a good invention are usually excited to tell you how it
works. Since they brag about 30 international patents for this,
there's no need to try to protect a trade secret. </p>
<p>5. This statement:</p>
<p>
</p><blockquote type="cite">The fins work like teeth in a comb, neatly
orienting air molecules to point in the same direction and
arranging them into columns. </blockquote>
<p></p>
<p>Based on my education, this statement seems to be completely
devoid of science. <br>
</p>
<p>This statement seems to defy the laws of physics. Last time I
checked, unless an atom or molecule is at absolute zero, it has
movement, whether it's spinning or vibrating, or both, so how can
they get air molecules to line up all in neat little rows, where
the molecules are all pointing the same way? </p>
<p>This also implies very laminar flow. As fluid velocity increases
that the diameter of the channel decreases, the Reynolds Number
increases. As the Reynold's number goes up, turbulence increases,
so mathematically, I would expect this flow to be tubulent, and
not laminar. From my classes on heat transfer, turbulent flow
around the heat transfer surface increases heat transfer, so
laminar flow in this case wouldn't be a good thing. <br>
</p>
<p>Until they can provide better comparisons with real servers in
real data center environments, I'm going to classify this as
"snake oil"<br>
</p>
<p><a class="gmail-m_8157281066646160146moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/Snake_oil" target="_blank">https://en.wikipedia.org/wiki/Snake_oil</a><br>
</p>
<pre class="gmail-m_8157281066646160146moz-signature" cols="72">Prentice</pre>
<div class="gmail-m_8157281066646160146moz-cite-prefix">On 1/24/19 3:54 PM,
<a class="gmail-m_8157281066646160146moz-txt-link-abbreviated" href="mailto:Chuck_Petras@selinc.com" target="_blank">Chuck_Petras@selinc.com</a> wrote:<br>
</div>
<blockquote type="cite">
<font size="2" face="sans-serif">Well, this is interesting.</font>
<br>
<br>
<font size="2" face="sans-serif">"According to Forced Physics’
<</font><a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__forcedphysics.com_&d=DwMFAw&c=-_uRSsrpJskZgEkGwdW-sXvhn_FXVaEGsm0EI46qilk&r=fawF3TRTwCqlaBkoLcxYCr4F4NRwCc64hmEgi9rHPpE&m=zr6lAlVphGxOQTXSElww9hGpqb9IZPik0_MN2v8Fqjs&s=lb4Hi9X8NKIYWe_e1RU3Cw4gr9Uz_B7n5pnCNY0ss3U&e=" target="_blank"><font color="blue" size="2" face="sans-serif">https://forcedphysics.com/</font>
[forcedphysics.com]</a><font size="2" face="sans-serif">>
chief technology officer, David Binger, the company’s conductor
can help
a typical data center eliminate its need for water or
refrigerants and
shrink its 22-MW load by 7.72 MW, which translates to an annual
reduction
of 67.6 million kWh. That data center could also save a total of
US $45
million a year on infrastructure, operating, and energy costs
with the
new system, according to Binger. “We are solving the problem
that electrons
create,” he said."</font>
<br>
<br>
<font size="2" face="sans-serif">A Cooler Cloud: A Clever Conduit
Cuts
Data Centers’ Cooling Needs by 90 Percent</font>
<br>
<a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__spectrum.ieee.org_energy_environment_a-2Dcooler-2Dcloud-2Da-2Dclever-2Dconduit-2Dcuts-2Ddata-2Dcenters-2Dcooling-2Dneeds-2Dby-2D90-2Dpercent&d=DwMFAw&c=-_uRSsrpJskZgEkGwdW-sXvhn_FXVaEGsm0EI46qilk&r=fawF3TRTwCqlaBkoLcxYCr4F4NRwCc64hmEgi9rHPpE&m=zr6lAlVphGxOQTXSElww9hGpqb9IZPik0_MN2v8Fqjs&s=VuDTSuinKPMpF6NCztFZkSGOVo3LD7MLjroIj_sn0ao&e=" target="_blank"><font color="blue" size="2" face="sans-serif">https://spectrum.ieee.org/energy/environment/a-cooler-cloud-a-clever-conduit-cuts-data-centers-cooling-needs-by-90-percent</font>
[spectrum.ieee.org]</a>
<br>
<font size="2" face="sans-serif"><br>
<br>
Chuck Petras, PE**<br>
Schweitzer Engineering Laboratories, Inc<br>
Pullman, WA 99163 USA<br>
</font><a href="http://www.selinc.com/" target="_blank"><font size="2" face="sans-serif">http://www.selinc.com</font></a><font size="2" face="sans-serif"><br>
<br>
SEL Synchrophasors - A New View of the Power System <</font><a href="http://synchrophasor.selinc.com/" target="_blank"><font size="2" face="sans-serif">http://synchrophasor.selinc.com</font></a><font size="2" face="sans-serif">><br>
<br>
Making Electric Power Safer, More Reliable, and More Economical
(R)<br>
<br>
** Registered in Oregon.<br>
</font>
<br>
<fieldset class="gmail-m_8157281066646160146mimeAttachmentHeader"></fieldset>
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