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<p>Eric, <br>
</p>
<p>I was suspecting that might be the case, but the explanations in
the other articles were way too vague to be sure of that. The
NextPlatform provided much better pictures. If that's the case,
this thing operates like a direct-expansion (DX) refrigeration
system, where the refrigerant is air and does not change state
from liquid to gas, like a typical DX refrigeration system, and
the induced-draft fan provides the shaft work, and those tiny
channels that allegedly line up the molecules act as many tiny
offices for the throttling process. Based on the pictures in the
Next Platform article, here is a crude drawing of cross-section of
one of these devices that I drew in Google Draw. It should help
you understand what's going inside this thing: <br>
</p>
<p><a class="moz-txt-link-freetext" href="https://docs.google.com/document/d/1UK94PxVlQtVSb2ns5TbCqHjPJ1vYSOmkGSeSorvHyaM/edit?usp=sharing">https://docs.google.com/document/d/1UK94PxVlQtVSb2ns5TbCqHjPJ1vYSOmkGSeSorvHyaM/edit?usp=sharing</a></p>
<p>Given this design, you can only have an induced-draft fan on the
outlet. A forced-draft fan on the inlet would compress the air,
heating it up and negating the throttling (or Joule-Thompson)
effect on the low-pressure side. <br>
</p>
<p>At the end of the day, thermodynamics still says X amount of
shaft work has to be done to provide Y amount of cooling through
this process, so I'm still skeptical of it, especially at scale. <br>
</p>
<p>And for those of you looking for something really boring to read
rather than work, here are the related patents. I haven't read
them myself. <br>
</p>
<p><a class="moz-txt-link-freetext" href="https://patents.google.com/patent/US8414847">https://patents.google.com/patent/US8414847</a></p>
<p><a class="moz-txt-link-freetext" href="https://patents.google.com/patent/US8986627B2">https://patents.google.com/patent/US8986627B2</a></p>
<p><a class="moz-txt-link-freetext" href="https://patents.google.com/patent/US10113774B2">https://patents.google.com/patent/US10113774B2</a><br>
</p>
<pre class="moz-signature" cols="72">Prentice</pre>
<div class="moz-cite-prefix">On 1/25/19 2:26 PM, Eric Moore wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CANGpa6CJf+yBkSj8mj=aWAWoSv3egu=Tq0B63VC+18hsTrLYqw@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<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/"
moz-do-not-send="true">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" moz-do-not-send="true">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"
moz-do-not-send="true">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" moz-do-not-send="true">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>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" moz-do-not-send="true">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"
moz-do-not-send="true">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" moz-do-not-send="true"><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" moz-do-not-send="true"><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"
moz-do-not-send="true"><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"
moz-do-not-send="true"><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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