Still interested in purely-radiant cooling.
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Green Xenon [Radium]
Please don't get upset at me. I posted something similar recently but
it didn't describe it properly.
I thinking of a cooling mechanism for houses and building in which the
cooling -- in the direct sense -- involves only radiation and no
convection at all. Sorta like a radiant-stove-top in reverse.
Indirectly, however, some amount of convection and conduction will be
needed [liquid helium, cold metals]. The cooling panel is the ceiling
and cools objects below it.
My visualization is that the radiant cooling panel contain extremely
cold metallic coils [cooled by liquid helium to almost absolute zero],
this would probably be deepest part of the panel.
http://en.wikipedia.org/wiki/Liquid_helium
Here, another question arises. Which is better to use -- Helium-3 or
Helium-4? Which one would have a stronger cooling effect if both were
at the same temperature?
The radiant cooling panel is the ceiling. It has 3 layers.
Layer 1: a material that allows heat radiation to pass through but is
a very poor conductor of heat
Layer 2: the same material found on the very top of radiant stove
tops
Layer 3: this is the deepest part containing the cool metallic coils.
Inside these coils are where the liquid helium would be flowing
through]
Layers 2 & 3 don't have any air molecules around them. The cold metal
coils are in a vacuum so they are not exposed to any air that would
solidify/liquefy. This means the space between layer 1 & 2 is also a
vacuum free of air.
There is dehumidification which is separate from the cooling.
Dehumidification is done by air processing devices on walls -- left,
right, back, front. These walls give out and take in air. There is
both re-circulation and fresh air. For fresh air, all vapors molecules
are let into the room -- excluding H20, CO2, gases with odors, toxic
vapors [such as CO], dust, irritating vapors, smoke or allergens. For
re-circulation, air in the room is sucked, cleaned [i.e. H20, CO2,
toxic vapors [such as CO], dust, irritating vapors, smoke and
allergens are removed] and then blown back into the room. In either
case, the amount of air-molecules-per-second-per-square-meter that is
sucked out of the room is the same is the amount of air-molecules-per-
second-per-square-meter the is blown into the room -- and visa versa.
Hence, the subject in the room doesn't feel any sucking or blowing.
The result is that the room now contains only N2 and O2 -- if you
exclude the CO2 and H2O-vapor emitted from the living subject[s]. The
N2 and O2 are kept at no less than least 70 degress Fahrenheit -- via
convection heating if the ambient temperature is less than 70 F -- to
prevent them from liquefying or solidifying. I know it's ironic that
the air would have to be heated in order to assist in preventing the
radiant cooler from failing. Still interesting, though.
Yes, heat absorbed into the radiant cooling panels is carried off
using convection -- but this is not what the subject inside the room
feels. The direct cooling effect on anything/anyone inside the room is
radiant.
Can anyone suggest a better manner for direct radiant cooling? If so,
please explain
By direct radiant cooling, I mean that if you place your body at a
noticeable distance from from panel, you'll feel cold because the
extreme cold of the coil will draw IR radiation away from your body.
OTOH, if you touch the panel, you won't feel as cold because the 1st
layer of the panel is a very poor conductor of heat.
On the ceiling, layer 1 is the lower than layer 2. Layer 3 is the
highest.
Thanks a bunch,
Radium
Noon-Air
"Green Xenon [Radium]" <gluce...@gmail.com> wrote in message
news:264fefe7-4fe8-470b...@w39g2000prb.googlegroups.com...
Maybe if you told us what the intended application is.....
I can't even visualize any application where it would be cost effective to
use a system like that. Just the liquid helium would make it cost
prohibitive.
Stormin Mormon
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"Green Xenon [Radium]" <gluce...@gmail.com> wrote in message
news:264fefe7-4fe8-470b...@w39g2000prb.googlegroups.com...
Green Xenon [Radium]
> Maybe if you told us what the intended application is.....
It is to keep a room comfortably cold during the summer.
>
> I can't even visualize any application where it would be cost effective to
> use a system like that. Just the liquid helium would make it cost
> prohibitive.
Call me weird but I prefer my cooling to be directly-radiant and
heating to directly involved natural convection of dry air. Just
something about radiant cooling that gets my interests going.
Green Xenon [Radium]
<cayoung61**spambloc...@hotmail.com> wrote:
> Give it up, you fool. Cold doesn't radiate.
It doesn't but it can cool you by causing you to radiate heat towards
it. The radiant cooler is cold, the subject in the room under the
cooler is hot. Physics will attempt to equalize the temperature of the
two objects. If there is no conduction or convection between the two
objects, then the attempt will be facilitated by making the hotter
object emit thermal radiation toward the colder object. This is will
cool the hotter object. If you are the hotter object, you will feel
cold under the radiant cooler.
Noon-Air
Maybe you should be looking at a system that will cost less than the house
its going into.
over a barrel
"Noon-Air" <Noon...@comcast.net> wrote in message
news:c6CdnR1rI_rAogHV...@comcast.com...
Not to mention such a system would instantly cause severe frostburn should
any body parts come into contact with it.
--
.p.jm@see_my_sig_for_address.com
<precision...@COLDmail.com> wrote:
>
>"Noon-Air" <Noon...@comcast.net> wrote in message
>news:c6CdnR1rI_rAogHV...@comcast.com...
>>
>> "Green Xenon [Radium]" <gluce...@gmail.com> wrote in message
>> news:a09972e7-1306-4f43...@n33g2000pri.googlegroups.com...
>> > On Aug 7, 4:28 pm, "Noon-Air" <Noon-...@comcast.net> wrote:
>> >
>> >> Maybe if you told us what the intended application is.....
>> >
>> > It is to keep a room comfortably cold during the summer.
>> >
>> >>
>> >> I can't even visualize any application where it would be cost effective
>> >> to
>> >> use a system like that. Just the liquid helium would make it cost
>> >> prohibitive.
>> >
>> > Call me weird but I prefer my cooling to be directly-radiant and
>> > heating to directly involved natural convection of dry air.
Seeing as you are totally unfamiliar with the terms you are
using, you should avoid using them
>Just
>> > something about radiant cooling that gets my interests going.
>>
>> Maybe you should be looking at a system that will cost less than the house
>> its going into.
>>
>
>Not to mention such a system would instantly cause severe frostburn should
>any body parts come into contact with it.
--
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Green Xenon [Radium]
wrote:
> Not to mention such a system would instantly cause severe frostburn should
> any body parts come into contact with it.
Why would frostbite occur? The lowest layer [the one a body part would
most likely contact] is an extremely poor conductor of heat, so it
wouldn't feel that cold. It's the radiant cooling, that would feel
cold.
Green Xenon [Radium]
> >> "Green Xenon [Radium]" <glucege...@gmail.com> wrote in message
> >>news:a09972e7-1306-4f43...@n33g2000pri.googlegroups.com...
> >> > Call me weird but I prefer my cooling to be directly-radiant and
> >> > heating to directly involved natural convection of dry air.
>
> Seeing as you are totally unfamiliar with the terms you are
> using, you should avoid using them
No offense but what makes you think I'm unfamiliar with those terms?
over a barrel
Okay I see now what your proposing is using an insulating barier over a
radiant heat reciever why Im surprised that I hadnt thought of this idea
before--I say go for it dude definately an open market for this type of
thing !!!
--
.p.jm@see_my_sig_for_address.com
The way you use them, and apparently fail to understand the
basic concepts of them.
Suggestion - study radiant heat, and how it works. Then
reverse the figures and see if 'radiant cooling' could ever work.
Keep in mind what I've said before about distance.
Think of this - stand next to a campfire on a cold night. up
close = toasty warm. 10 feet away = cold. That is radiant heat in
action. The power falls off as the square of the distance. "radiant
cooling', if there were such a thing ( there is not, just as there is
no such thing as 'cold', there is only 'absence of heat' ) would work
exactly the same.
And when you heat a house, you do NOT want 'dry air'. Even
if you could have it, which you can't.
Green Xenon [Radium]
> Think of this - stand next to a campfire on a cold night. up
> close = toasty warm. 10 feet away = cold.
The overwhelming majority of heat emitted from a fire, is convective
heat, not radiant heat. There is some radiant heat but it is very
small compared to the convection heat.
> That is radiant heat in
> action.
> The power falls off as the square of the distance. "radiant
> cooling', if there were such a thing ( there is not, just as there is
> no such thing as 'cold', there is only 'absence of heat' ) would work
> exactly the same.
Um, the human body can give of heat via radiation as well as
conduction and convection. If you put your hand near a piece of
extremely cold metal, you'll feel a perceptible amount of cold even if
you don't touch the metal. This is an example of radiant cooling.
There is a sharp difference in temperature between your hand and the
cold metal. Physics wants to equalize the temperature and will attempt
in whatever way possible to do so. If you are not touching the metal
[a painful conductive cooling], then the next option to equalize the
temperature is for your hand to emit IR radiation and warm the metal.
In this case, your hand is the thermal radiator. Your hand emits
radiant heat toward the cold metal.
To your hand, this is radiant cooling. For the cold metal, it is an
example of radiant heating, because the IR radiation from your hand
will warm up the metal.
>
> And when you heat a house, you do NOT want 'dry air'.
Why not?
> Even
> if you could have it, which you can't.
What makes hot dry air impossible?
B-Hate-Me
"Green Xenon [Radium]" <gluce...@gmail.com> wrote in message
news:264fefe7-4fe8-470b...@w39g2000prb.googlegroups.com...
> Hi:
>
> Please don't get upset at me. I posted something similar recently but
> it didn't describe it properly.
>
> I thinking of a cooling mechanism for houses and building in which the
> cooling -- in the direct sense -- involves only radiation and no
> convection at all. Sorta like a radiant-stove-top in reverse.
How about you just shut the fuck up and go to
one of the may kook groups.
AMF
--
SOME PEOPLE ARE LIKE SLINKIES - NOT REALLY GOOD FOR ANYTHING BUT THEY BRING
A
SMILE TO YOUR FACE WHEN PUSHED DOWN THE STAIRS.
Noon-Air
"over a barrel" <precision...@COLDmail.com> wrote in message
news:1_adncrWdfgQxAPV...@scnresearch.com...
Sounds like a winner to me... now *prove* to me that it works, and can be
sold and installed at a competitive price, retrofit without major
construction, with a reasonable profit margin, and can be used in most any
cooling application, then I'll run with it.
geothermaljones
How much energy will be needed to maintain it in a liquid form?
How much pressure will there be in the circuit when the Helium vaporizes
while absorbing the heat?
If we're to put multiple air handlers around the space to dehumidify, how
would said dehumidification take place.
Your suggesting some sort of fresh air introduction while exhausting bad
indoor air. -Google HRV/ERV-
When dehumidifying, what's going to "dry" the air? You'll need some sort of
cold coil to accomplish this.
Since 70dF 50% RH conditions are what most seek, it's not coincidental that
55dF 100% air is what's needed to accomplish this.
as 55dF 100%RH air warms to 70dF the RH levels out at about 50%. -Google
Psychrometric Chart-
If we're to cool these air handlers with liquid helium as well, refer to the
first 3 Questions.
If rather, you use, say, a DX coil for this, wouldn't you be able to find
these parts & pieces (& UL Listed) at much more reasonable rates?
Further, wouldn't using a single air handling unit with some sort of
distribution system, say ductwork, provide a much more cost effective &
serviceable system?
The sucking & blowing folks would "never" feel can easily be covered with
proper placement & balance of said distribution system.
Since the building does not have to be structurally re-enforced to carry the
weight of the helium containment vessel & panel system, the costs up front
could be reduced.
Since the electrical system doesn't have to support the power requirements
of maintaining liquid helium, the cost of operation would also be lowered.
Since many homes require heating during some portions of the year, wouldn't
it make sense to provide a simple, sensible (& UL Listed) system for
delivering this as well?
Since Heat seeks cold, in any case, the radiant source would be the people
rather than the (INSULATED?) ceiling panels.
Since Radiant heat is directly proportional to the square of the distance
from the heat source. -Google Dulong & Petit, Boyles Law, Newton, etc...-
This would mean the fat bald 6' guy (Hey, I resemble that remark) would have
a terribly cold head while his feet were still hot.
I could be wrong, but I'm skeptical...
goodluck
geothermaljones
"Green Xenon [Radium]" <gluce...@gmail.com> wrote in message
news:264fefe7-4fe8-470b...@w39g2000prb.googlegroups.com...
Green Xenon [Radium]
wrote:
> How big is the liquid Helium pressure vessel?
> How much energy will be needed to maintain it in a liquid form?
> How much pressure will there be in the circuit when the Helium vaporizes
> while absorbing the heat?
>
> If we're to put multiple air handlers around the space to dehumidify, how
> would said dehumidification take place.
> Your suggesting some sort of fresh air introduction while exhausting bad
> indoor air. -Google HRV/ERV-
> When dehumidifying, what's going to "dry" the air? You'll need some sort of
> cold coil to accomplish this.
> Since 70dF 50% RH conditions are what most seek, it's not coincidental that
> 55dF 100% air is what's needed to accomplish this.
> as 55dF 100%RH air warms to 70dF the RH levels out at about 50%. -Google
> Psychrometric Chart-
> If we're to cool these air handlers with liquid helium as well, refer to the
> first 3 Questions.
Ok. Thanks for this info. I just thought that liquid helium gets the
coldest of all gases at absolute zero.
> If rather, you use, say, a DX coil for this, wouldn't you be able to find
> these parts & pieces (& UL Listed) at much more reasonable rates?
Yes.
> Further, wouldn't using a single air handling unit with some sort of
> distribution system, say ductwork, provide a much more cost effective &
> serviceable system?
Exactly.
> The sucking & blowing folks would "never" feel can easily be covered with
> proper placement & balance of said distribution system.
Ok.
> Since the building does not have to be structurally re-enforced to carry the
> weight of the helium containment vessel & panel system, the costs up front
> could be reduced.
Yes.
This helium thing was mostly a theoretical system I was interested in.
I'm interested in a lot of things that are either impossible or barely
in the realm of possibility.
> Since the electrical system doesn't have to support the power requirements
> of maintaining liquid helium, the cost of operation would also be lowered.
Absolutely.
> Since many homes require heating during some portions of the year, wouldn't
> it make sense to provide a simple, sensible (& UL Listed) system for
> delivering this as well?
>
Yes. My theoretical system would involve the floor emitting hot dry
air. This convective floor heating is designed in such as way that
those on the floor will feel the heat but will not fell any sucking or
blowing of air.
The design also ensures that the hot air has absolutely no water vapor
or CO2 at all. In addition, this design keeps the air on the lowest
part of the house [the air on the ground of the lowest floor] the
hottest [using dry convective heat], while things just below the
ceiling of the highest floor get the coldest [because of radiant
cooling].
Lot of these theoretical things I talk about are way too hypothetical
to be true today but they interest me and stir my imagination.
It's my nature to want the opposite of what exists. I think there is
too much radiant heating and convective cooling. Hence, I want radiant
cooling and convective heating.
> Since Heat seeks cold, in any case, the radiant source would be the people
> rather than the (INSULATED?) ceiling panels.
Yes. That's what I've been trying to tell everyone. The humans in the
room are the thermal radiators and the ceilings absorb that radiant
heat.
The ceiling is a thermal non-conductive so that if you touch it, the
ceiling won't really feel cold but if you are just below the ceiling w/
out touching it, you will feel cold. The ceiling is made of a material
that is extremely poor at conducting heat but clearly allows IR [heat]
radiation to pass through.
At the maximum cold setting, if you put your hand just below the
ceiling of the highest room of the house [usually the 2nd/3rd floor],
your hand will get as cold as it can get w/out causing injury.
As for the convection heating in winter, when set on maximum, the air
just above the ground of the lowest room of the house [usually the
first floor but sometimes the basement -- if the house has a basement]
gets as hot as it can without causing injury.
Even at max, the solid part of the floor itself, doesn't get so hot,
but the air right above it does. In the winter, what feels better than
some hot dry air under your feet!
> Since Radiant heat is directly proportional to the square of the distance
> from the heat source. -Google Dulong & Petit, Boyles Law, Newton, etc...-
> This would mean the fat bald 6' guy (Hey, I resemble that remark) would have
> a terribly cold head while his feet were still hot.
I'd just love that cold feeling on top and hot on bottom. I enjoy the
rarities.
geothermaljones
> coldest of all gases at absolute zero.
WTF???
Everything is at it's coldest at absolute zero... Helium, Oxygen, Bananas,
Snot, what ever.
in fact, everything stops moving at absolute zero. -Google Absolute Zero-
When you get to Absolute zero, there are throngs of people that will laud
your name...
Mankind has never been there, albeit a few hundredths of a degree away...
but a man's gotta dream.
For the time being, find a NG that deals with intriguing mind benders, this
isn't it.
I see I've wasted my time.
I'll have to defer to the rest of those that said get lost.
You've proven yourself to be The Absolute Zero!
eabof
geothermaljones
Green Xenon [Radium]
wrote:
Sorry, I meant to say "I just thought that helium has the lowest
boiling point." Of all gases it requires the lowest temperature to
liquefy. To make helium liquid, one requires temperatures at or near 0
K.
Green Xenon [Radium]
wrote:
> Even at max, the solid part of the floor itself, doesn't get so hot,
> but the air right above it does. In the winter, what feels better than
> some hot dry air under your feet!
As with the ceiling, the material that makes up the floor is also
extremely poor at conducting heat. In addition, though, the floor is
completely opaque to IR light [i.e. radiant heat]. Hence that only way
the floor's heat can be felt is through convection.
Dry convective heat only.
More interesting facts:
The lowest part of the house [ground of the basement or 1st floor] has
the lowest air pressure, while the ceiling of the higher part of the
house [usually 2nd or 3rd floor] has the highest air pressure. This
makes life more intriguing. Higher pressure with less heat. Lower
pressure with more heat. Thats how it should be.
.p.jm@see_my_sig_for_address.com
<geother...@comcast.net> wrote:
>> Ok. Thanks for this info. I just thought that liquid helium gets the
>> coldest of all gases at absolute zero.
>
>WTF???
>Everything is at it's coldest at absolute zero... Helium, Oxygen, Bananas,
>Snot, what ever.
>in fact, everything stops moving at absolute zero. -Google Absolute Zero-
>When you get to Absolute zero, there are throngs of people that will laud
>your name...
Naaah - they'll give you the cold shoulder.
>Mankind has never been there, albeit a few hundredths of a degree away...
>but a man's gotta dream.
>For the time being, find a NG that deals with intriguing mind benders, this
>isn't it.
>I see I've wasted my time.
>I'll have to defer to the rest of those that said get lost.
>You've proven yourself to be The Absolute Zero!
>
> eabof
> geothermaljones
>
--
Bob Shuman
residential freezer. It too is very cold inside, but has "an extremely poor
conductor of heat" (an insulator) on the outside "where it is most likely to
come into contact" with any heat source.
How well does the outside wall of that freezer collect the heat radiated
from your body when you are a few feet or even a few inches away?
While I think that innovation starts with "outside the box" thinking, I
believe that it still must be based on the laws of THIS universe.
Bob
"Green Xenon [Radium]" <gluce...@gmail.com> wrote in message
news:cc11db56-a0c1-4fc2...@i24g2000prf.googlegroups.com...
.p.jm@see_my_sig_for_address.com
<resh...@removethis.alcatel-lucent.com> wrote:
>Sounds like you are describing something that is in every kitchen: a
>residential freezer.
No. It works primarily via convection. Even the old 'cold
plate' fan-less ones ( as slow as they were to cool ).
> It too is very cold inside, but has "an extremely poor
>conductor of heat" (an insulator) on the outside "where it is most likely to
>come into contact" with any heat source.
>
>How well does the outside wall of that freezer collect the heat radiated
>from your body when you are a few feet or even a few inches away?
Once the heat is radiated from your body, it is gone ( to you
). It's not going to turn around and come back if it fails to find a
place to go.
Also, ;picture standing in front of a campfire - your face can
get too hot, while your ass freezes.
A very small percentaqe of the heat you radiate goes in any
one particular direction, and the amount that falls on the 'receiving
/ absorbing surface' will thusly decrease as the square of the
distance from it.
>
>While I think that innovation starts with "outside the box" thinking, I
>believe that it still must be based on the laws of THIS universe.
Takes all the fun out of engineering .....
>
> Bob
>
>"Green Xenon [Radium]" <gluce...@gmail.com> wrote in message
>news:cc11db56-a0c1-4fc2...@i24g2000prf.googlegroups.com...
>> On Aug 9, 4:48 pm, "over a barrel" <precisionmachin...@COLDmail.com>
>> wrote:
>>
>>> Not to mention such a system would instantly cause severe frostburn
>>> should
>>> any body parts come into contact with it.
>>
>> Why would frostbite occur? The lowest layer [the one a body part would
>> most likely contact] is an extremely poor conductor of heat, so it
>> wouldn't feel that cold. It's the radiant cooling, that would feel
>> cold.
>>
>
--
nicks...@ece.villanova.edu
> A very small percentaqe of the heat you radiate goes in any
>one particular direction, and the amount that falls on the 'receiving
>/ absorbing surface' will thusly decrease as the square of the
>distance from it.
Not if the surface completely encloses you. The MRT is solid angles weighted
by their temperatures. Multiply each area your body sees by its temp, add
the products, and divide by the total area of a reference sphere surrounding
you, containing the individual areas. You might radiate 50% to a large close
wall. As you walk away from a large wall, the near-field view factor might
still be about 50%.
And we don't need liquid helium. The MRT graph here:
http://heatkit.com/html/guide2.htm#MasonryHeating
says we can be comfy in 90 F air with 40 F walls, in a bunny-free room.
Some buildings have chilled beams and ceilings for cooling. A chilled
floor would make more sense, since warm air rises. A slow ceiling fan
with an occupancy sensor and a room temp thermostat could stir up some
floor air as needed for comfort.
Nick
.p.jm@see_my_sig_for_address.com
><.p.jm@see_my_sig_for_address.com> wrote:
>
>> A very small percentaqe of the heat you radiate goes in any
>>one particular direction, and the amount that falls on the 'receiving
>>/ absorbing surface' will thusly decrease as the square of the
>>distance from it.
>
>Not if the surface completely encloses you.
Good point, Nick.
If you happen to be sitting inside a radiant-absorptive ball (
a thermal variation of a Dyson Sphere, perhaps, Scotty ? ).
> The MRT is solid angles weighted
>by their temperatures. Multiply each area your body sees by its temp, add
>the products, and divide by the total area of a reference sphere surrounding
>you, containing the individual areas. You might radiate 50% to a large close
>wall. As you walk away from a large wall, the near-field view factor might
>still be about 50%.
>
>And we don't need liquid helium. The MRT graph here:
>
>http://heatkit.com/html/guide2.htm#MasonryHeating
>
>says we can be comfy in 90 F air with 40 F walls, in a bunny-free room.
>
>Some buildings have chilled beams and ceilings for cooling. A chilled
So do many many cold rooms of various applications. Ever hear
of static-coil ammonia systems ? They do not work primarily by
raidant absorption, they work mainly by convection currents. If you
were to put the coils at the floor instead of the ceiling, they
wouldn't work worth a shit.
>floor would make more sense, since warm air rises. A slow ceiling fan
>with an occupancy sensor and a room temp thermostat could stir up some
>floor air as needed for comfort.
And thus, it is no longer a radiant system, it is convective.
Hey, here's one to work on - what if you took a bunch of Bucky
Balls IE Fullerenes, and froze them, then dumped them all in a room ?
Pls post your code for designing it when you get a chance :-)
nicks...@ece.villanova.edu
>>... Some buildings have chilled beams and ceilings for cooling.
>
> So do many many cold rooms of various applications. Ever hear
>of static-coil ammonia systems ?
No. I'm mainly interested in houses, altho I've read that a 70 F low-e
ceiling can reduce ice rink melting by 10 watts/ft^2...
>They do not work primarily by raidant absorption, they work mainly by
>convection currents.
Cool air falls...
>If you were to put the coils at the floor instead of the ceiling, they
>wouldn't work worth a shit.
There would be more cool surface, but maybe less cooling, with no slow
ceiling fan.
>>... a cool floor would make more sense, since warm air rises. A slow
>>ceiling fan with an occupancy sensor and a room temp thermostat could
>>stir up some floor air as needed for comfort.
>
> And thus, it is no longer a radiant system, it is convective.
Most of the cooling might be convective, but consider that a) a ceiling
needs well-distributed cool sources in order to have a large radiant or
convective surface, but we might cool an entire floor with a single point
source, since cool air falls, and b) a slow ceiling fan can provide more
air velocity for useful low-energy cooling, allowing a higher room air
temp for the same comfort, and c) a radiant cool floor can allow a higher
air temp, for the same comfort, and d) with a slow ceiling fan, it's easier
to turn off the cooling when nobody's in the room.
Nick
Andy Energy
wrote:
This sounds sooo complicated.
Why do we humans seem to think we need a complicated solution to a
simple problem.
We cannot even get the whole building industry to what is right.
I’d put my money on great insulation, proper shading, controlled
ventilation, proper sized and correctly installed HVAC.
Look into the Austrian Passive house.
Andy
Think and do "Whole House Performance"
phil scott
this is correct... 40F walls in a warm room create convection... it is
conduction from skin to air that removes the highest percentage of
heat from a human body.... convection provides the air flow... same
with cold beams etc.... (and evaporation of water from the skin)...
radiation is a factor but its a minor factor n the termperature
differrential range are discussing....load calc books have the math
for all of this..... on a roof though with the hot sun, radiation is a
huge factor, same though glass, convection not withstanding.
Phil scott
Phil scott
nicks...@ece.villanova.edu
>> >... The MRT graph here:
>>
http://heatkit.com/html/guide2.htm#MasonryHeating
>>
>> >says we can be comfy in 90 F air with 40 F walls...
>this is correct... 40F walls in a warm room create convection... it is
>conduction from skin to air that removes the highest percentage of
>heat from a human body....
I disagree. You can't cool 92 F skin much with 90 F air.
Nick
John, A.
How do I configure Agent to ignore the messages from this guy?
On Sat, 09 Aug 2008 20:02:08 -0400, .p.jm@see_my_sig_for_address.com
wrote:
.p.jm@see_my_sig_for_address.com
So piss off, little pussy bitch.
--
Don Ocean
> I am using Agent
> How do I configure Agent to ignore the messages from this guy?
Easily accomplished.. Hit the off switch on your computer and never turn
it on again.
Old and Grunpy
tony
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