I have been offered a small (about the size of a water
cooler) liquid nitrogen generator at an attractive
price. It generates four and a half liters per day,
using a gravity feed to keep a half liter dewar filled.
I want to pump the liquid nitrogen into a hole drilled
into the heatsinks of the CPU and GPU of a gaming PC
so I can overclock them ****her than otherwise possible.
(This is for a a "just for fun" personal project, not
for work).
My question is how best to pump the liquid nitrogen.
In the past I have worked with big dewars and let them
self-pressurize with a relief valve on top and a feed
tube going to the bottom -- sort of like an aerosol
can. This doesn't look feasible in this case; the back
pressure seems like it will back up the gravity feed.
I think I need a small pump that can take the cold and
not add too much heat to the liquid nitrogen. Any ideas?
BTW, I have seven old 500 MHz. Pentium 3 systems that
are ready to be scrapped that I will be doing my
initial experiments on before deciding whether to
risk a more modern PC.
"Guy Macon" <http://www.guymacon.com/> wrote in message
news:A_6dncuGjuhtK_Ta4p2dnAA@giganews.com...
>
>
>
> I have been offered a small (about the size of a water
> cooler) liquid nitrogen generator at an attractive
> price. It generates four and a half liters per day,
> using a gravity feed to keep a half liter dewar filled.
>
> I want to pump the liquid nitrogen into a hole drilled
> into the heatsinks of the CPU and GPU of a gaming PC
> so I can overclock them ****her than otherwise possible.
> (This is for a a "just for fun" personal project, not
> for work).
>
> My question is how best to pump the liquid nitrogen.
> In the past I have worked with big dewars and let them
> self-pressurize with a relief valve on top and a feed
> tube going to the bottom -- sort of like an aerosol
> can. This doesn't look feasible in this case; the back
> pressure seems like it will back up the gravity feed.
> I think I need a small pump that can take the cold and
> not add too much heat to the liquid nitrogen. Any ideas?
>
> BTW, I have seven old 500 MHz. Pentium 3 systems that
> are ready to be scrapped that I will be doing my
> initial experiments on before deciding whether to
> risk a more modern PC.
>
> --
> Guy Macon
> <http://www.guymacon.com/>
>
Let me be the first to say, "that's going to be cool." :-)
Mike
Guy Macon wrote:
> I have been offered a small (about the size of a water
> cooler) liquid nitrogen generator at an attractive
> price. It generates four and a half liters per day,
> using a gravity feed to keep a half liter dewar filled.
>
> I want to pump the liquid nitrogen into a hole drilled
> into the heatsinks of the CPU and GPU of a gaming PC
> so I can overclock them ****her than otherwise possible.
> (This is for a a "just for fun" personal project, not
> for work).
>
> My question is how best to pump the liquid nitrogen.
> In the past I have worked with big dewars and let them
> self-pressurize with a relief valve on top and a feed
> tube going to the bottom -- sort of like an aerosol
> can. This doesn't look feasible in this case; the back
> pressure seems like it will back up the gravity feed.
> I think I need a small pump that can take the cold and
> not add too much heat to the liquid nitrogen. Any ideas?
>
> BTW, I have seven old 500 MHz. Pentium 3 systems that
> are ready to be scrapped that I will be doing my
> initial experiments on before deciding whether to
> risk a more modern PC.
>
It would be easier to deal with the boiloff gas - it's still at 77K.
Do you actually need the LN2?
On Thu, 20 Dec 2007 00:27:26 +0000, Guy Macon
<http://www.guymacon.com/> wrote:
>
>
>
>I have been offered a small (about the size of a water
>cooler) liquid nitrogen generator at an attractive
>price. It generates four and a half liters per day,
>using a gravity feed to keep a half liter dewar filled.
>
>I want to pump the liquid nitrogen into a hole drilled
>into the heatsinks of the CPU and GPU of a gaming PC
>so I can overclock them ****her than otherwise possible.
>(This is for a a "just for fun" personal project, not
>for work).
>
>My question is how best to pump the liquid nitrogen.
>In the past I have worked with big dewars and let them
>self-pressurize with a relief valve on top and a feed
>tube going to the bottom -- sort of like an aerosol
>can. This doesn't look feasible in this case; the back
>pressure seems like it will back up the gravity feed.
>I think I need a small pump that can take the cold and
>not add too much heat to the liquid nitrogen. Any ideas?
>
>BTW, I have seven old 500 MHz. Pentium 3 systems that
>are ready to be scrapped that I will be doing my
>initial experiments on before deciding whether to
>risk a more modern PC.
The only thing that comes to mind is pumps used for liquid fuel
rockets.
On Wed, 19 Dec 2007 18:21:56 -0800, "Paul Hovnanian P.E."
<paul@hovnanian.com> wrote:
>Guy Macon wrote:
>>
>> I have been offered a small (about the size of a water
>> cooler) liquid nitrogen generator at an attractive
>> price. It generates four and a half liters per day,
>> using a gravity feed to keep a half liter dewar filled.
>>
>> I want to pump the liquid nitrogen into a hole drilled
>> into the heatsinks of the CPU and GPU of a gaming PC
>> so I can overclock them ****her than otherwise possible.
>> (This is for a a "just for fun" personal project, not
>> for work).
>
>What's the temperature spec on the CPU you will be using? Odds are that
>it won't deal with LN2 temperatures well.
>
>Consider the heat capacity of LN2 (include the heat of vaporization)
>compared to that of H2O. For the complexity of what you propose to do,
>LN2 won't buy you much more than a good heat exchanger/radiator setup.
>
>Also, keep in mind that in an enclosed space (your mom's basement? ;-))
>the nitrogen gas will displace air and asphyxiate the user if not
>properly ventilated.
Guy Macon wrote:
>
> I have been offered a small (about the size of a water
> cooler) liquid nitrogen generator at an attractive
> price. It generates four and a half liters per day,
> using a gravity feed to keep a half liter dewar filled.
>
> I want to pump the liquid nitrogen into a hole drilled
> into the heatsinks of the CPU and GPU of a gaming PC
> so I can overclock them ****her than otherwise possible.
> (This is for a a "just for fun" personal project, not
> for work).
What's the temperature spec on the CPU you will be using? Odds are that
it won't deal with LN2 temperatures well.
Consider the heat capacity of LN2 (include the heat of vaporization)
compared to that of H2O. For the complexity of what you propose to do,
LN2 won't buy you much more than a good heat exchanger/radiator setup.
Also, keep in mind that in an enclosed space (your mom's basement? ;-))
the nitrogen gas will displace air and asphyxiate the user if not
properly ventilated.
--
Paul Hovnanian mailto:Paul@Hovnanian.com
------------------------------------------------------------------
ASCII stupid question, get a stupid ANSI!
'Guy Macon' wrote, in part:
| I have been offered a small (about the size of a water
| cooler) liquid nitrogen generator at an attractive
| price. It generates four and a half liters per day,
| using a gravity feed to keep a half liter dewar filled.
_____
You could just Google a search string that includes [ overclocking CPU
liquid Nitrogen ] and get over 94,000 hits. Most (if not all) these Rube
Goldberg devices just build a tank around the CPU heatsink, fill the tank
with liquid Nitrogen and let it boil off as it may. For actually pumping
liquid nitrogen you could contact NASA for a few tips... especially safety
tips.
Taking a flyer with a Pentium III is hardly worth the effort.
One possibility for a more or less continuously operating cooler would be to
use the boil-off of liquid nitrogen to chill an anti-freeze mixture
(propylene glycol & water ~ 50:50 should be good to below - 40) that you
could then pump through a more or less stock CPU water block.
Phil Weldon
"Guy Macon" <http://www.guymacon.com/> wrote in message
news:A_6dncuGjuhtK_Ta4p2dnAA@giganews.com...
|
|
|
|
| I want to pump the liquid nitrogen into a hole drilled
| into the heatsinks of the CPU and GPU of a gaming PC
| so I can overclock them ****her than otherwise possible.
| (This is for a a "just for fun" personal project, not
| for work).
|
| My question is how best to pump the liquid nitrogen.
| In the past I have worked with big dewars and let them
| self-pressurize with a relief valve on top and a feed
| tube going to the bottom -- sort of like an aerosol
| can. This doesn't look feasible in this case; the back
| pressure seems like it will back up the gravity feed.
| I think I need a small pump that can take the cold and
| not add too much heat to the liquid nitrogen. Any ideas?
|
| BTW, I have seven old 500 MHz. Pentium 3 systems that
| are ready to be scrapped that I will be doing my
| initial experiments on before deciding whether to
| risk a more modern PC.
|
| --
| Guy Macon
| <http://www.guymacon.com/>
|
Guy Macon wrote:
> I have been offered a small (about the size of a water
> cooler) liquid nitrogen generator at an attractive
> price. It generates four and a half liters per day,
> using a gravity feed to keep a half liter dewar filled.
>
> I want to pump the liquid nitrogen into a hole drilled
> into the heatsinks of the CPU and GPU of a gaming PC
> so I can overclock them ****her than otherwise possible.
> (This is for a a "just for fun" personal project, not
> for work).
>
> My question is how best to pump the liquid nitrogen.
> In the past I have worked with big dewars and let them
> self-pressurize with a relief valve on top and a feed
> tube going to the bottom -- sort of like an aerosol
> can. This doesn't look feasible in this case; the back
> pressure seems like it will back up the gravity feed.
> I think I need a small pump that can take the cold and
> not add too much heat to the liquid nitrogen. Any ideas?
>
> BTW, I have seven old 500 MHz. Pentium 3 systems that
> are ready to be scrapped that I will be doing my
> initial experiments on before deciding whether to
> risk a more modern PC.
>
There is a whole forum devoted to LN2 and dry ice here.
Maybe someone here will have an answer.
Dirk Bruere at NeoPax wrote:
>
>Guy Macon <http://www.guymacon.com/> wrote:
>> I want to pump the liquid nitrogen into a hole drilled
>> into the heatsinks of the CPU and GPU of a gaming PC
>> so I can overclock them ****her than otherwise possible.
>
>It would be easier to deal with the boiloff gas - it's still at 77K.
>Do you actually need the LN2?
Yup. The latent heat of evaporation for Nitrogen is 198.3 Joules
per gram at one atmosphere, while the the specific heat capacity
for nitrogen is only 1.006 Joules per gram per degree Kelvin.
Also, liquids conduct heat far better than gasses.
I don't have an uploadable cooling curve for nitrogen
at hand, but take a look at the cooling curve for water:
[ http://www.physchem.co.za/Heat/Graphics/Heat42.gif ].
The portion of the curve labled D shows that the energy
needed to go from 99.99 degrees C to 100.01 degrees C
is much larger than from 0.01 degrees C to 99.99
degrees C. This is typical of boiling liquids.
>What's the temperature spec on the CPU you will be using?
>Odds are that it won't deal with LN2 temperatures well.
Others have done it without any problems. Semiconductors as a
rule do not mind LN2 temperatures as long as you avoid thermal
shock and icing. Besides, overclockers pretty much expect to
lose a few if they push the envelope.
>Consider the heat capacity of LN2 (include the heat of vaporization)
>compared to that of H2O. For the complexity of what you propose to do,
>LN2 won't buy you much more than a good heat exchanger/radiator setup.
It will buy me minus 196 degrees, and others who have tried it have
reported a stable system with a 3GHz. CPU overclocked to 5GHz.
>Also, keep in mind that in an enclosed space (your mom's basement? ;-))
>the nitrogen gas will displace air and asphyxiate the user if not
>properly ventilated.
Nope. that's for systems with a *source* of nitrogen. A nitrogen
generator takes as much out of the room air as the boiling nitrogen
puts back in. (I would ventalate it anyway, but for the opposite
reason; to avoid any Oxygen concentration around the generator)
Pumping Liquid Nitrogen 
Linear Mode
