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<blockquote type="cite"> I suspect though that you need servers
engineered to fit onto their heatsinks.<br>
</blockquote>
</p>
<p>This is the main crux of my previous criticism for direct-contact
liquid-cooling solutions, the cooling piping and heat exchanger(s)
can be retrofit to existing server designs with minimal
re-engineering. And even for immersive cooling, you just remove
the case altogether, or make it completely sealed to contain the
coolant, both of which require minimal re-engineering. This
solution looks like it would require major rethinking of how
components are organized. <br>
</p>
<pre class="moz-signature" cols="72">Prentice </pre>
<div class="moz-cite-prefix">On 1/28/19 12:24 PM, John Hearns wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAPqNE2Vc9_OM9XZyDHmJetY2yqVVfnL=XKmV1vhJsUSkP+_VQw@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div>Prentice, the website refers to Open Compute racks.
"... technology has been designed to fit into standard
Open Compute racks".</div>
<div>So yep, 19 inch racks are not being targeted here. But
OCP is pretty widespread.</div>
<div>I would really like to find out if they can retrofit
these to existing kit. I suspect though that you need
servers engineered to fit onto their heatsinks.</div>
<div><span style="text-align:left;color:rgb(255,255,255);text-transform:none;text-indent:0px;letter-spacing:0px;font-family:myriad-pro;font-size:22px;font-style:normal;font-variant:normal;font-weight:400;text-decoration:none;word-spacing:0px;display:inline;white-space:pre-wrap;word-wrap:break-word;float:none;background-color:transparent"><span style="text-align:left;color:rgb(255,255,255);text-transform:none;text-indent:0px;letter-spacing:0px;font-family:myriad-pro;font-size:22px;font-style:normal;font-variant:normal;font-weight:400;text-decoration:none;word-spacing:0px;display:inline;white-space:pre-wrap;word-wrap:break-word;float:none;background-color:transparent">orced Physics cooling technology has been designed to fit into Standard Open Compute Racks. </span>orced Physics cooling technology has been designed to fit into Standard Open Compute Racks. </span></div>
<div><br>
</div>
</div>
</div>
</div>
<br>
<div class="gmail_quote">
<div class="gmail_attr" dir="ltr">On Mon, 28 Jan 2019 at 16:48,
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;padding-left:1ex;border-left-color:rgb(204,204,204);border-left-width:1px;border-left-style:solid">
<div bgcolor="#FFFFFF">
<p>So I was thinking about this over the weekend (because I
apparently have nothing better to do with my time), and I
definitely think this is a non-starter due to the massive
change in server hardware layout to accommodate this
thing. Yes, blades, and twin form factor servers already
required that, and they're common form factors, but those
form factors were just a matter of shrinking or changing
the layout of the motherboard but still look like
"traditional" layouts to the untrained eye, and they were
still designed with typical front-to-back air cooling in
mind. I feel like re-arranging the layout of components to
accomodate this thing is a just more of a change than the
market will accept. <br>
</p>
<p>Just my 2 cents. <br>
</p>
<pre class="gmail-m_-4339801130891775252moz-signature" cols="72">Prentice </pre>
<div class="gmail-m_-4339801130891775252moz-cite-prefix">On
1/25/19 3:56 PM, Prentice Bisbal wrote:<br>
</div>
<blockquote type="cite">
<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="gmail-m_-4339801130891775252moz-txt-link-freetext"
href="https://docs.google.com/document/d/1UK94PxVlQtVSb2ns5TbCqHjPJ1vYSOmkGSeSorvHyaM/edit?usp=sharing"
target="_blank" moz-do-not-send="true">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="gmail-m_-4339801130891775252moz-txt-link-freetext"
href="https://patents.google.com/patent/US8414847"
target="_blank" moz-do-not-send="true">https://patents.google.com/patent/US8414847</a></p>
<p><a
class="gmail-m_-4339801130891775252moz-txt-link-freetext"
href="https://patents.google.com/patent/US8986627B2"
target="_blank" moz-do-not-send="true">https://patents.google.com/patent/US8986627B2</a></p>
<p><a
class="gmail-m_-4339801130891775252moz-txt-link-freetext"
href="https://patents.google.com/patent/US10113774B2"
target="_blank" moz-do-not-send="true">https://patents.google.com/patent/US10113774B2</a><br>
</p>
<pre class="gmail-m_-4339801130891775252moz-signature" cols="72">Prentice</pre>
<div class="gmail-m_-4339801130891775252moz-cite-prefix">On
1/25/19 2:26 PM, Eric Moore wrote:<br>
</div>
<blockquote type="cite">
<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/"
target="_blank" 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 class="gmail-m_-4339801130891775252gmail_attr"
dir="ltr">On Fri, Jan 25, 2019 at 11:33 AM Prentice
Bisbal via Beowulf <<a
href="mailto:beowulf@beowulf.org" target="_blank"
moz-do-not-send="true">beowulf@beowulf.org</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px
0px
0.8ex;padding-left:1ex;border-left-color:rgb(204,204,204);border-left-width:1px;border-left-style:solid">
<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_-4339801130891775252gmail-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_-4339801130891775252gmail-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_-4339801130891775252gmail-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_-4339801130891775252gmail-m_8157281066646160146moz-signature" cols="72">Prentice</pre>
<div
class="gmail-m_-4339801130891775252gmail-m_8157281066646160146moz-cite-prefix">On
1/24/19 3:54 PM, <a
class="gmail-m_-4339801130891775252gmail-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_-4339801130891775252gmail-m_8157281066646160146mimeAttachmentHeader"></fieldset>
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