carneyke wrote:

Yeah, I am a little behind the times (Climate Change terminology being
in Vouge). On a serious note, this summer I read an article on
automobile registration in the USA. In 1975 (year I graduated from High
School) there were roughly 130 million cars registered. Today it is
around 280 million cars (I may be off on these numbers slightly).
Anyway, if you remember, cars ran at 160 degree F back then and today
they run at 200 degree F. They also have that hot little catalytic
converter. I truly believe, the doubling of cars (with catalytic
converters) and the 25 % increase in engine temperature must have some
effect on the atmosphere. I know this has been kicked around but the
article really opened my eyes to the heat generated by cars. I guess
this is a case of fixing one problem and creating another. Take Care
.....

200°F is NOT a 25% increase over 160°F. What a useless LUSER.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Reg Edwards wrote:

But yes, all those
Land Rovers and Rolls and Jags are energy hogs.

=================================

Amongst the most polluting of energy hogs are aircraft engines.

Ban all motor vehicles and airliners and let the World slow down!


Great idea, Reg. We'll start with your neighborhood. No
electricity, no running water, no food deliveries, no sewage system. No
high speed transportation also means little or no medical care, The
world won't "Slow down", but billions of people will die. Maybe we
should ban morons first?


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"John Popelish" wrote in message
...
Don Klipstein wrote:
(snip)
Looks like some recent record-big blizzards did not stop the world from
having its hottest year on record as a continuation of a recent-decades
upward trend, and less lignificantly the USA from having its hottest
January on record - should one more blizzard make much difference?

Global warming does not necessarily imply less snow, since warmer air
holds more moisture than colder air, allowing it to deliver more snow.
Only when global warming brings a particular location above the freezing
point, does it imply rain instead of snow. Expect places that normally
have had dry, cold winters to have warmer winters with lots more snow.
Till it gets lots warmer.

My daffodils started blooming in January, here on the west coast of Canada!

Steve R.

"Rich Grise" wrote in message
news
On Mon, 13 Feb 2006 18:03:39 -0500, Ed Huntress wrote:
"carneyke" wrote in message
oups.com...
I think my point is for everything we do there
will always be a "bad" side and its a shame it gets so political. So
please accept my appollogy for being rude and as Jim wrote "Ignorant".
Sorry Jim.....

Gee, you must be coming from an awfully polite newsgroup. g

FWIW, most of the fuel you burn in your car goes out the tailpipe. A
super-efficient spark-ignition engine turns something like 24% of its
fuel
into motive power (if my memory of this number is not accurate, someone
please correct me; I haven't looked it up for years). Of that, something
like 60% makes it to the drive wheels. So a spark-ignition-engined car,
on a
good day, delivers somewhere around 15% of the thermal potential of the
fuel, as motive power to the wheels.

It doesn't get a lot better with other engine types. A large, efficient,
stationary diesel is good for something like 28% at the shaft. The
number is
similar for a huge, stationary, multi-stage steam turbine. And, believe
it
or not, also for a Stirling, running with helium or hydrogen for a
working
fluid, at very high internal gas pressure and with a high-efficiency
heat
exchanger at each end.

Sucks, doesn't it? And that's on a good day. d8-)

Speaking of losing memory neurons, I seem to recall seeing a sort of
diagram, back in the '50's, when they had flat-head straight 6's, that
something like 2% of the potential power in the fuel actually got to the
wheels.

Ha! Well, they may have exaggerated that a bit g, but the percentage is
very low. Flatheads were pretty awful from a thermal-efficiency
standpoint -- too much combustion-chamber surface area relative to
combustion-chamber volume.

There were HUGE thermal losses, and friction, and yadda yadda yadda...

Yeah, sometimes you have to wonder how they go anywhere at all. d8-)

Compare that with a hydrogen fuel cell: up to 80% or so, without fancy
cogeneration. The electric motor it powers also is around 80% efficient, for
something like 64% overall efficiency.

Unfortunately, producing the hydrogen is not that efficient. No free lunch,
once again.

--
Ed Huntress

Rich Grise wrote:

On Mon, 13 Feb 2006 23:32:42 +0000, Pooh Bear wrote:
Reg Edwards wrote:

But yes, all those
Land Rovers and Rolls and Jags are energy hogs.

Amongst the most polluting of energy hogs are aircraft engines.

Ban all motor vehicles and airliners and let the World slow down!

Airbus quote 3 litres of fuel used per 100 pasenger km - approx
equivalent to ~ 50 UK mpg or ~ 40 US mpg. Better than a car with a
sole occupant at least.

Of course the long distance of many airline flights means a large
amount of fuel is used. Chances are most ppl would think twice about
the need to visit their their destination if they had to drive.


I've been on a couple of excruciatingly long overseas flights - like,
14 hours of cruising across the Pacific[1], and I wonder where the hell
they keep all of that fuel? The fuel lines on those engines are, like,
2" (5 cm) or so in diameter! (well, the ones I've seen on USAF fighter
jets.)

The wings are very capacious. Longest I've had to endure was 13 hours btw.
Long enough.

Graham

"Rich Grise" wrote in message
news
On Tue, 14 Feb 2006 00:09:30 +0000, Pooh Bear wrote:
Ed Huntress wrote:
Even electricity generation is no better than 37% efficient
apparently (
recent
UK figure ).

Well, even that is somewhat higher than I recall, because the
steam-turbine
example above is for one engaged in generating electricity.

However, my memory isn't that precise, and is getting less so, and
technology no doubt has improved. A turbine's practical efficiency
isn't a
factor of theoretical heat cycles as much as it is a matter of how much
heat
and erosion it can tolerate.

I came across that figure in a thread in another ng recently. Apparently
up from
35% only a few years ago. There's been quite a lot of new generation
built
recently in the UK using natural gas which may explain the improvement.
It also
entertainly shows how short term thinking ( natural gas is cheap - so
lets burn
it ) can blow up in your face !


In regard to gas turbines, I visited Pratt & Whitney's engine division
decades ago on a press junket, to hear them tell us how they'd raised
the
operating temperature of a jet engine by roughly 100 degrees F, from
2,200
to 2,300 degrees. I remarked that didn't really sound very impressive.
An
old P&W engineer sitting next to me said, "Son [I was much younger then
g]," there are men here who would sell their grandmothers for another
hundred degrees."

A friend of mine works in aeropsace design. I'm awed by the tricks they
use to
cool those turbine blades. They would melt otherwise !


I was on a document coding project where somebody was suing somebody else
about inferior turbine blades. They're like, a single crystal of titanium
that's grown in a mold, and if you drop one on the floor, you have to
scrap it. I think maybe even if you touch it with bare fingers, you have
to scrap it. It seems a new jet engine is about $2,000,000.00, but an
overhaul, where they basically replace all of the turbine blades and
bearings, is only about $250,000.00. Or, was in the 1990's. :-)

The single-crystal technology was what that press conference was all about.
P&W invented it around 1978 or so. But the metal is a superalloy (a
high-temperature alloy of nickel, cobalt, etc.), not titanium.

They grow the crystal from a pool of molten metal, pulling the mold and
blade out of the pool in a way similar to the way silicon crystals for
semiconductors are grown. Very impressive to watch.

I don't think it's particularly delicate, but you wouldn't want to drop one.
They cool those blades in the engine by blowing air through a series of tiny
holes that are eroded along the lengths of the blades by EDM or ECM
(electrical-discharge machining or electrochemical machining).

Because a gas turbine (jet engine, or turboshaft engine) has no cooling
cycle, the peak flame temperatures can only be around half those in an
automobile engine. That's why car engines are more efficient than turbines:
efficiency is directly related to peak temperature of the cycle.

--
Ed Huntress

John Devereux wrote:

Pooh Bear writes:

Ken Smith wrote:

In article ,
Charles Schuler wrote:
[...]
Global warming is a widely disputed theory.

The warming isn't very disputed. It is the cause that is being argued
about these days.

Very true.

Even the US contingent that say it's *not* due to human activity don't dismiss
the effect of CO2 in the atmosphere though AFAIK. They simply dispute how much
an influence it is.

The sane conclusion therefore is to limit CO2 ( and other greenhouse gas )
emissions since it can at worst do no harm to do so !

Judging from some responses I see here, the USA will go directly from
"there's no problem" to "it's *too late* to do anything about it
anyway". Skipping entirely the "it looks like there is a problem,
perhaps we shouldn't make it worse" phase.

Sadly, I suspect it may indeed be too late. Bye-bye Florida ( for example ).

Graham

Dave Hinz wrote:

On Mon, 13 Feb 2006 22:43:08 GMT, Rich Grise wrote:

I'd be willing to bet real money that if the USA stood down their military,
and called off all of the invasions and crusades and other mischief
they're perpetrating all over the world, that worldwide oil consumption
would decrease by 25-50%.

I'd be willing to bet real money that you just pulled that number out of
your ass.


I'll bet that you're right. I'll bet that's where he keeps all his
numbers. ;-)

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"Ed Huntress" wrote in message
...

Unfortunately, producing the hydrogen is not that efficient. No free
lunch,
once again.


It is fairly efficient cracking a hydrocarbon to produce H2 - improving the
efficiency of the use of fossil fuel by about 100 % also has utility.

Messing around with pure hydrogen is silly and represents the typical
eco-loon thinking I.M.O - there is a vast infrastructure for handling
hydrogen when wrapped in a liquid but there is none for pure H2.

"Rich Grise" wrote in message
news
I'd be willing to bet real money that if the USA stood down their
military,
and called off all of the invasions and crusades and other mischief
they're perpetrating all over the world, that worldwide oil consumption
would decrease by 25-50%.

I think you are right:

Left to themselves at least 1/3 of the middle east population would Darwin
themselves within a decade or so; The turmoil would destroy the Oil fields
first as they are the sole source of income of the opposing factions. That
would represent a drop in supplies by 25% - 50% over the decade - depending
on what the mitigation strategies of the developed world would be.

In rec.crafts.metalworking Ed Huntress wrote:
(snip)
Compare that with a hydrogen fuel cell: up to 80% or so, without fancy
cogeneration. The electric motor it powers also is around 80% efficient, for
something like 64% overall efficiency.

Unfortunately, producing the hydrogen is not that efficient. No free lunch,
once again.

--
Ed Huntress

Well, they could start bulding nuclear power plants and use the excess
night time capacity to electrolyse the hydrogen out of water. Several
advantages are much lower CO2 production from removing the coal fired
plants. Not to mention getting rid of the thousands of tons of uranium
and thorium that are dumped into the air from coal plants:
http://www.ornl.gov/info/ornlreview/...t/colmain.html
And if they would allow the reprocessing of the fuel rods it would cut
down dramatically on the amount of waste produced. And while the
remaining waste is much hotter, it lasts for signifigantly less time.

Todd Rich wrote:

And if they would allow the reprocessing of the fuel rods it would cut
down dramatically on the amount of waste produced.

In the UK the pollution associated with nuclear energy comes primarily from the
*re-processing* !

And while the
remaining waste is much hotter, it lasts for signifigantly less time.

You *are* joking ? How on earth can you make that statement ? The scary stuff
doesn't just 'go away' !

Graham

Mike,
200 - 160 = 40 (Correct ?)
40 degree increase over 160 degree = 25 % (Correct ?)
Sorry, but you are the LUSER
See what I mean about having common sense.
That's why your broke and I'm not.........

200°F is NOT a 25% increase over 160°F. What a useless LUSER.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

In rec.crafts.metalworking Pooh Bear wrote:


Todd Rich wrote:

And if they would allow the reprocessing of the fuel rods it would cut
down dramatically on the amount of waste produced.

In the UK the pollution associated with nuclear energy comes primarily from the
*re-processing* !

And while the
remaining waste is much hotter, it lasts for signifigantly less time.

You *are* joking ? How on earth can you make that statement ? The scary stuff
doesn't just 'go away' !

Graham

What is the half-life of U-235?

What is the half-life of Co-60?

Which one is hotter?

And please note that I did *NOT* say it just goes away. The waste from
reprocessing needs to be stored for at least a thousand years. However
storing is a lot better than breathing the radioactive materials that are
being produced in coal-fired plants right now. And the volume of material
that needs to be stored is signifigantly less than un-reprocessed waste.

"Frithiof Andreas Jensen"
wrote in message ...

"Ed Huntress" wrote in message
...

Unfortunately, producing the hydrogen is not that efficient. No free
lunch,
once again.


It is fairly efficient cracking a hydrocarbon to produce H2 - improving
the
efficiency of the use of fossil fuel by about 100 % also has utility.

Messing around with pure hydrogen is silly and represents the typical
eco-loon thinking I.M.O - there is a vast infrastructure for handling
hydrogen when wrapped in a liquid but there is none for pure H2.

If by "wrapped in a liquid" you mean carried in methanol, the problem with
that is that fuel-cell conversion efficiency drops from around 80% to 30 -
40% when you do that.

No free lunch.

--
Ed Huntress

carneyke wrote:

Mike,
200 - 160 = 40 (Correct ?)
40 degree increase over 160 degree = 25 % (Correct ?)

Flawed. Fahrenheit isn't a measure of absolute temperature.


Sorry, but you are the LUSER
See what I mean about having common sense.
That's why your broke and I'm not.........

You're truly an idiot of the grand order.

I suggest you go back to school.

Graham

"carneyke" wrote in message
oups.com...
Mike,
200 - 160 = 40 (Correct ?)
40 degree increase over 160 degree = 25 % (Correct ?)

Real scientists measure temperature using absolute temperature scales.
Redoing your math:

669 - 629 = 40 (Correct!)

40 degree increase over 629 = 6.4%. (Correct!)

"Todd Rich" wrote in message
...
In rec.crafts.metalworking Ed Huntress wrote:
(snip)
Compare that with a hydrogen fuel cell: up to 80% or so, without fancy
cogeneration. The electric motor it powers also is around 80% efficient,
for
something like 64% overall efficiency.

Unfortunately, producing the hydrogen is not that efficient. No free
lunch,
once again.

--
Ed Huntress

Well, they could start bulding nuclear power plants and use the excess
night time capacity to electrolyse the hydrogen out of water. Several
advantages are much lower CO2 production from removing the coal fired
plants. Not to mention getting rid of the thousands of tons of uranium
and thorium that are dumped into the air from coal plants:
http://www.ornl.gov/info/ornlreview/...t/colmain.html
And if they would allow the reprocessing of the fuel rods it would cut
down dramatically on the amount of waste produced. And while the
remaining waste is much hotter, it lasts for signifigantly less time.

Nuclear is an attractive option for generating electricity, and hydrogen. In
terms of efficiency, however, the total system is still pretty low.

--

Todd Rich wrote:

In rec.crafts.metalworking Pooh Bear wrote:

Todd Rich wrote:

And if they would allow the reprocessing of the fuel rods it would cut
down dramatically on the amount of waste produced.

In the UK the pollution associated with nuclear energy comes primarily from the
*re-processing* !

And while the
remaining waste is much hotter, it lasts for signifigantly less time.

You *are* joking ? How on earth can you make that statement ? The scary stuff
doesn't just 'go away' !

Graham

What is the half-life of U-235?

What is the half-life of Co-60?

I'm sure you can find the precise data for that very readily on the net or at Wikipedia.

That's not the point though. Used nuclear fuel contains a rich mix of fission products
you haven't mentioned some of which have very long half lives and some with very high
toxicity.


Which one is hotter?

You can't make any direct simple comparison. Radioactivity of any active element will
vary with time.


And please note that I did *NOT* say it just goes away. The waste from
reprocessing needs to be stored for at least a thousand years.

Much much longer. 100,000 yrs at least.


However
storing is a lot better than breathing the radioactive materials that are
being produced in coal-fired plants right now.

The stuff that goes up the chimneys isn't U235 !


And the volume of material
that needs to be stored is signifigantly less than un-reprocessed waste.

Not so. Reprocessing creates vast quantities of highly radioactive and acidic liquid
waste. The main problem at BNFL's Sellafield site.

Also - what do you do with the plutonium ?

Graham

"Why" wrote in message
...
"Steve B" wrote in message
news:8EcIf.38834$JT.22325@fed1read06...
Good ****ing grief, Charlie Brown.

Do you ever watch the weather?

You know, when they say the high today was 46, and in 1941, the high
for
today was 66? If global warming was a reality, and the temperature
rose
since 1941, it probably would have been 146 degrees today!

Temperatures are freaky spikes in nature. Up one year and down the
next.

Reading anything else into it is utter paranoia.

Get over it. Or go get some therapy.

Steve

Steve, is that supposed to be an argument regarding global warming? I'm
serious here. I think an average 10-year-old can do better.

You're looking at ONE DAY, comparing ONE PAIR OF YEARS. Does the inanity
of
that not strike you right between the eyes?

I mean, c'mon. Nobody is that numb.

Gee, ED, in 1974 waiting in a gas line the radio was warning us about
the coming global freeze. Remember that ED?

Yeah, and do you remember who wrote the book about it? A very conservative
fellow was telling us that. g

Still, you have a non-argument here. You've gone from one-day arguments
about multi-decade trends, to news reports from one year in the last
century.

Is this how you make business presentations in your work?

--
Ed Huntress

In rec.crafts.metalworking Ed Huntress wrote:
(snip)
Nuclear is an attractive option for generating electricity, and hydrogen. In
terms of efficiency, however, the total system is still pretty low.

True, but the total pool you are drawing from is pretty large...

carneyke wrote:

Mike,
200 - 160 = 40 (Correct ?)
40 degree increase over 160 degree = 25 % (Correct ?)

No, it is not correct, because absolute zero is not equal to 0° F.

Sorry, but you are the LUSER
See what I mean about having common sense.
That's why your broke and I'm not.........

You are hopeless, and your intellectual account is overdrawn.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"Ed Huntress" wrote in message
...
"Steve B" wrote in message
news:8EcIf.38834$JT.22325@fed1read06...
Good ****ing grief, Charlie Brown.

Do you ever watch the weather?

You know, when they say the high today was 46, and in 1941, the high for
today was 66? If global warming was a reality, and the temperature rose
since 1941, it probably would have been 146 degrees today!

Temperatures are freaky spikes in nature. Up one year and down the next.

Reading anything else into it is utter paranoia.

Get over it. Or go get some therapy.

Steve

Steve, is that supposed to be an argument regarding global warming? I'm
serious here. I think an average 10-year-old can do better.

You're looking at ONE DAY, comparing ONE PAIR OF YEARS. Does the inanity
of
that not strike you right between the eyes?

I mean, c'mon. Nobody is that numb.

--
Ed Huntress


No, the inanity is the same fact that the world is estimated to have a
finite lifetime, and that it will probably end in a few hundred million
years, or in 2012 by meteor impact as predicted by several ancient
societies.

Point is, global warming won't really affect anyone for such a long time
that they won't have to worry about it in their (our)(your)(my) lifetime,
and all this sniveling is boring and annoying.

Steve

In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %, no matter where you are in
the world. Jeez, lighten up.........

Pooh Bear wrote:
carneyke wrote:

Mike,
200 - 160 = 40 (Correct ?)
40 degree increase over 160 degree = 25 % (Correct ?)

Flawed. Fahrenheit isn't a measure of absolute temperature.


Sorry, but you are the LUSER
See what I mean about having common sense.
That's why your broke and I'm not.........

You're truly an idiot of the grand order.

I suggest you go back to school.

Graham

Sorry, but you are the LUSER
See what I mean about having common sense.
That's why your broke and I'm not.........

"LUSER"

"your" instead of "you're"

????

It is very obvious who's the uneducated idiot.

Steve

"carneyke" wrote in message
oups.com...
In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %, no matter where you are in
the world. Jeez, lighten up.........

Pooh Bear wrote:
carneyke wrote:

Mike,
200 - 160 = 40 (Correct ?)
40 degree increase over 160 degree = 25 % (Correct ?)

Flawed. Fahrenheit isn't a measure of absolute temperature.

You're getting 'way off track here. Temperature is not a measure of how much
heat an object radiates, or conducts, or convects. Heat is a product of
temperature and *volume*, or "quantity."

Again, this is high school physics. If you want to know how much heat a car
gives off, or a catalytic converter, you have to know the pre- and
post-heating temperature of a *given mass of material* that it's heating:
air, water, or whatever.

A large volume of air heated to 160 degrees, to use one of your examples,
transfers more heat to the atmosphere than a small volume of air heated to
200 degrees. Capice?

--
Ed Huntress

In article .com,
says...
In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %, no matter where you are in
the world. Jeez, lighten up.........

All right. My temperature scale is (F-160)*5/4. Now what's the
(percentage) rise? Hint: It's still 6.4%.

Jeez, wise up.....

--
Keith

Pooh Bear wrote:
carneyke wrote:

Mike,
200 - 160 = 40 (Correct ?)
40 degree increase over 160 degree = 25 % (Correct ?)

Flawed. Fahrenheit isn't a measure of absolute temperature.


Sorry, but you are the LUSER
See what I mean about having common sense.
That's why your broke and I'm not.........

You're truly an idiot of the grand order.

I suggest you go back to school.

Graham

carneyke wrote:

In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %,

The numerical increase is 25 % *only* because you've used the freezing
point of water as an arbitrary reference. Real science uses *absolute*
temperature.

Do you know what absolute temperature is ?

no matter where you are in
the world. Jeez, lighten up.........

Learn some science !

Graham

"Steve B" wrote in message
news:iVmIf.38880$JT.22959@fed1read06...

Point is, global warming won't really affect anyone for such a long time
that they won't have to worry about it in their (our)(your)(my) lifetime,
and all this sniveling is boring and annoying.

So, be bored and annoyed. The next generation may not be bored. They'll
wonder why so many inane arguments showed up in a discussion of great
importance.

They'll think their parents were insane. To an alarming degree, they
probably will be right.

--
Ed Huntress

On Tue, 14 Feb 2006 16:03:48 +0000, the renowned Pooh Bear
wrote:



carneyke wrote:

In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %,

The numerical increase is 25 % *only* because you've used the freezing
point of water as an arbitrary reference. Real science uses *absolute*
temperature.

I think I'd be more concerned about the rise above average ambient in
this case. If that's 70°F, and the numbers above are correct, the
difference is about 100%.

But, of course, temperature difference doesn't indicate what the total
heat loss is, and heat engines run more efficiently with a larger
difference from ambient, so all other things being equal you'd have
less total heat loss. A Maglite flashight bulb runs much hotter than a
range element, but uses only a tiny fraction of the power.

Do you know what absolute temperature is ?

no matter where you are in
the world. Jeez, lighten up.........

Learn some science !

Graham


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

In article ,
what says...
On Tue, 14 Feb 2006 11:03:19 -0500, the renowned Keith Williams
wrote:

In article .com,
says...
In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %, no matter where you are in
the world. Jeez, lighten up.........

All right. My temperature scale is (F-160)*5/4. Now what's the
(percentage) rise? Hint: It's still 6.4%.

Jeez, wise up.....

Is this still a sci group (or a practical group in the case of rcm)???

Heat loss is a function of temperature *difference* to the ambient, so
you are all wrong. So there. It's more like 100%. Of course heat
engines get more efficient when they have a larger temperature
difference to work with, so the total heat loss, all other things
being equal, would be less.

Engine (Carnot Cycle) efficiency is related to absolute temperature
difference, not some man-made scale.

Temperature difference is only one
factor-- a Maglite(tm) flashight bulb runs much hotter than a range
element, but uses only a tiny fraction of the power.

Because its temperature is *higher* more energy is radiated in the
visible range. It's not really that hard to figure out.

--
Keith

On Tue, 14 Feb 2006 11:03:19 -0500, the renowned Keith Williams
wrote:

In article .com,
says...
In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %, no matter where you are in
the world. Jeez, lighten up.........

All right. My temperature scale is (F-160)*5/4. Now what's the
(percentage) rise? Hint: It's still 6.4%.

Jeez, wise up.....

Is this still a sci group (or a practical group in the case of rcm)???

Heat loss is a function of temperature *difference* to the ambient, so
you are all wrong. So there. It's more like 100%. Of course heat
engines get more efficient when they have a larger temperature
difference to work with, so the total heat loss, all other things
being equal, would be less. Temperature difference is only one
factor-- a Maglite(tm) flashight bulb runs much hotter than a range
element, but uses only a tiny fraction of the power.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

I work in a calibration lab, doing temperature work on a regular basis.
Scary having someone like me turning pots !
U guy's are to much...... Excuse me, You guys are too much.
Well, now that I've created unnecessary hate and discontent throughout
the world, it's time to bid farewell...
Thank you for everyone that corrected me. I did learn a thing or two.

Do you know what absolute temperature is ?
Learn some science !

Graham

On Tue, 14 Feb 2006 11:42:46 -0500, the renowned Keith Williams
wrote:

In article ,
says...
On Tue, 14 Feb 2006 11:03:19 -0500, the renowned Keith Williams
wrote:

In article .com,
says...
In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %, no matter where you are in
the world. Jeez, lighten up.........

All right. My temperature scale is (F-160)*5/4. Now what's the
(percentage) rise? Hint: It's still 6.4%.

Jeez, wise up.....

Is this still a sci group (or a practical group in the case of rcm)???

Heat loss is a function of temperature *difference* to the ambient, so
you are all wrong. So there. It's more like 100%. Of course heat
engines get more efficient when they have a larger temperature
difference to work with, so the total heat loss, all other things
being equal, would be less.

Engine (Carnot Cycle) efficiency is related to absolute temperature
difference, not some man-made scale.

Yes. Though I think an IC gas engine is Otto cycle, no?

Temperature difference is only one
factor-- a Maglite(tm) flashight bulb runs much hotter than a range
element, but uses only a tiny fraction of the power.

Because its temperature is *higher* more energy is radiated in the
visible range.

And because it's so much smaller and better insulated less total
energy per unit time is radiated, convected or conducted.

It's not really that hard to figure out.

There are people out there who think big trucks are less efficient
than small trucks just because they look huge and guzzle more gas.
Of course when you calculate the gasoline consumption per unit of
freight (volume or weight) you find the bigger ones are better if you
can keep them reasonably full.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

In rec.crafts.metalworking Pooh Bear wrote:
Todd Rich wrote:
In rec.crafts.metalworking Pooh Bear wrote:
Todd Rich wrote:

And if they would allow the reprocessing of the fuel rods it would cut
down dramatically on the amount of waste produced.

In the UK the pollution associated with nuclear energy comes primarily from the
*re-processing* !

And while the
remaining waste is much hotter, it lasts for signifigantly less time.

You *are* joking ? How on earth can you make that statement ? The scary stuff
doesn't just 'go away' !

Graham

What is the half-life of U-235?
Roughly 700 million years.
Specific activity is 0.0000022 Ci/g
http://www.ead.anl.gov/pub/doc/uranium.pdf


What is the half-life of Co-60?
5.24 years.
Specific activity is 1,100 Ci/g
http://www.ead.anl.gov/pub/doc/cobalt.pdf


I'm sure you can find the precise data for that very readily on the net
or at Wikipedia.

I already knew the answers. The question was asked to see if you knew, or
were willing to find out.

That's not the point though. Used nuclear fuel contains a rich mix of
fission products you haven't mentioned some of which have very long half
lives and some with very high toxicity.

Yes, long half-lives means lower radioactivity.

Which one is hotter?

You can't make any direct simple comparison. Radioactivity of any
active element will vary with time.

I'm not sure exactly what you mean here. I'm trying to point out that
highly active elements have shorter half-lives. If you are pointing out
that as an element decays into other isotopes before ending in a stable
isotope that some of the daughter isotopes might have a higher specific
acitive than a parent isotope, then yes, that is true, but irrelevant.

And please note that I did *NOT* say it just goes away. The waste from
reprocessing needs to be stored for at least a thousand years.

Much much longer. 100,000 yrs at least.

Which isotope are you referring to? Bet it has a low specific activity,
and isn't considered a high level waste product. Plus it can probably be
converted into a usable fuel, or a higher specific activity isotope that
will decay faster. Using the technology for reverberatory thorium nuclear
power plants you can 'burn up' quite a few isotopes and recover energy
from them. You wind up with hotter waste than uranium power plants, but
then again it has to be stored for less time.
http://www.uic.com.au/nip47.htm

However
storing is a lot better than breathing the radioactive materials that are
being produced in coal-fired plants right now.

The stuff that goes up the chimneys isn't U235 !

Did you bother to even read the Oak Ridge report I linked to? Here is a
highlight for you:

:Based on the predicted combustion of 2516 million tons of coal in the
:United States and 12,580 million tons worldwide during the year 2040,
:cumulative releases for the 100 years of coal combustion following 1937
:are predicted to be:

:U.S. release (from combustion of 111,716 million tons):
:Uranium: 145,230 tons (containing 1031 tons of uranium-235)

:Thorium: 357,491 tons

:Worldwide release (from combustion of 637,409 million tons):

:Uranium: 828,632 tons (containing 5883 tons of uranium-235)

:Thorium: 2,039,709 tons

Note that this is estimated totals for 35 years in the future, but for a
typical plant in 1982:

:For the year 1982, assuming coal contains uranium and thorium
:concentrations of 1.3 ppm and 3.2 ppm, respectively, each typical plant
:released 5.2 tons of uranium (containing 74 pounds of uranium-235) and
:12.8 tons of thorium that year



And the volume of material
that needs to be stored is signifigantly less than un-reprocessed waste.

Not so. Reprocessing creates vast quantities of highly radioactive and
acidic liquid waste. The main problem at BNFL's Sellafield site.

Which is then further processed into a lower volume solid.

http://www.uic.com.au/ne5.htm
http://www.uic.com.au/nip72.htm

Also - what do you do with the plutonium ?

Graham

You do know that you can use it for fuel in nuclear power plants? Or don't
you?
http://www.uic.com.au/nip18.htm

On Tue, 14 Feb 2006 05:48:18 +0000, Pooh Bear wrote:
John Devereux wrote:
Pooh Bear writes:
Ken Smith wrote:
Charles Schuler wrote:
[...]
Global warming is a widely disputed theory.

The warming isn't very disputed. It is the cause that is being argued
about these days.

Very true.

Even the US contingent that say it's *not* due to human activity don't dismiss
the effect of CO2 in the atmosphere though AFAIK. They simply dispute how much
an influence it is.

The sane conclusion therefore is to limit CO2 ( and other greenhouse gas )
emissions since it can at worst do no harm to do so !

Judging from some responses I see here, the USA will go directly from
"there's no problem" to "it's *too late* to do anything about it
anyway". Skipping entirely the "it looks like there is a problem,
perhaps we shouldn't make it worse" phase.

Sadly, I suspect it may indeed be too late. Bye-bye Florida ( for example ).

Well, (A), so what? and (B), I imagine we'll figure out a way to muddle
through - humans can be pretty resourseful, you know. :-) Like, just look
at NO,LA - they got the dikes up and the city pumped out in less than a
year!

What happens with the harbors might be interesting. ;-) This is all
ass-u-me-ing, of course, that the Chicken Littles are "right", the ice
caps are going to melt, and the sea's going to rise 100 feet or whatever.
;-)

Cheers!
Rich
--
"We have met the enemy and he is us." - Pogo Possum

On Tue, 14 Feb 2006 12:02:01 +0000, Pooh Bear wrote:
Todd Rich wrote:

And if they would allow the reprocessing of the fuel rods it would cut
down dramatically on the amount of waste produced.

In the UK the pollution associated with nuclear energy comes primarily from the
*re-processing* !

And while the
remaining waste is much hotter, it lasts for signifigantly less time.

You *are* joking ? How on earth can you make that statement ? The scary stuff
doesn't just 'go away' !


Yes, that's the point - that's exactly what it does, eventually. Remember
"half-life"? ;-)

Cheers!
Rich
--
"We have met the enemy and he is us." - Pogo Possum

On Tue, 14 Feb 2006 04:17:30 -0800, carneyke wrote:

Mike,
200 - 160 = 40 (Correct ?)
40 degree increase over 160 degree = 25 % (Correct ?)
Sorry, but you are the LUSER
See what I mean about having common sense.
That's why your broke and I'm not.........

200°F is NOT a 25% increase over 160°F. What a useless LUSER.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

200F ~= 384K
160F ~= 362K
delta = 22K

22K = 362K * 6%.

Hope This Helps!
Rich

On Tue, 14 Feb 2006 11:43:52 -0500, Spehro Pefhany wrote:
On Tue, 14 Feb 2006 11:03:19 -0500, the renowned Keith Williams
says...
In the original post I was speaking in Fahrenheit not Celcius or
Kelvin. An increase from 160 to 200 is 25 %, no matter where you are in
the world. Jeez, lighten up.........

All right. My temperature scale is (F-160)*5/4. Now what's the
(percentage) rise? Hint: It's still 6.4%.

Jeez, wise up.....

Is this still a sci group (or a practical group in the case of rcm)???

Heat loss is a function of temperature *difference* to the ambient, so
you are all wrong. So there. It's more like 100%. Of course heat
engines get more efficient when they have a larger temperature
difference to work with, so the total heat loss, all other things
being equal, would be less. Temperature difference is only one
factor-- a Maglite(tm) flashight bulb runs much hotter than a range
element, but uses only a tiny fraction of the power.

Heh. I had a physics teacher that used a kewl example. He lit a match,
and asked, "Which of thse is hotter, the match or a bathtub full of
hot water? The match, of course. *Ow!*" tosses match stub "But
which has more heat? Let me put it this way - which can melt more
ice cubes?"

Cheers!
Rich

Richard the Dreaded Libertarian wrote:

On Tue, 14 Feb 2006 12:02:01 +0000, Pooh Bear wrote:
Todd Rich wrote:

And if they would allow the reprocessing of the fuel rods it would cut
down dramatically on the amount of waste produced.

In the UK the pollution associated with nuclear energy comes primarily from the
*re-processing* !

And while the
remaining waste is much hotter, it lasts for signifigantly less time.

You *are* joking ? How on earth can you make that statement ? The scary stuff
doesn't just 'go away' !


Yes, that's the point - that's exactly what it does, eventually. Remember
"half-life"? ;-)

Actaully it never 'goes awy' at all. There's always some radioactivity there.

Btw. I meant reprocessing doesn't make the radioactivity go away.

Graham