Does Carnot efficiency e = 1 - Tc/Th apply to all heat engines?

[Dave]

Working through steam engines and the Carnot efficient given by:

e = 1 - Tc/Th

In the Carnot cycle, there are some statements like "ideal gas".
However in the real world, steam is a not an ideal gas, it has "magic"
compression thanks to quenching. So I think that perhaps the Carnot
cycle efficiency might be being over applied to all heat engines i.e.
ones which are not Carnot engines.

The efficiency also isn't demonstrated as being really any different
from using steam, e.g. 101C with steam, to not using steam e.g. 99C at 1
ATM. I'm not suggesting that higher temperatures aren't more efficient,
just that the gains might not be worth all the extra cost, mass, effort,
and risk of high pressure, high temperature steam.

I'm working though if work can be obtained from low pressure steam, with
pressure reduction from a head. Need to consider vapour pressure etc.
Even might get to use a N. Tesla one-way pipe/valve.

[Jim Pennino]

Post by Dave
e = 1 - Tc/Th
In the Carnot cycle, there are some statements like "ideal gas".
However in the real world, steam is a not an ideal gas, it has "magic"
compression thanks to quenching. So I think that perhaps the Carnot
cycle efficiency might be being over applied to all heat engines i.e.
ones which are not Carnot engines.

Rather than magic, it sounds more like you don't know what quenching
actually is and does.

Post by Dave
The efficiency also isn't demonstrated as being really any different
from using steam, e.g. 101C with steam, to not using steam e.g. 99C at 1
ATM. I'm not suggesting that higher temperatures aren't more efficient,
just that the gains might not be worth all the extra cost, mass, effort,
and risk of high pressure, high temperature steam.

324 years of use and actual experience says you are pissing in the wind.

If your daydream were actual reality someone would have noticed long
ago.

[Dave]

Post by Jim Pennino

Post by Dave
e = 1 - Tc/Th
In the Carnot cycle, there are some statements like "ideal gas".
However in the real world, steam is a not an ideal gas, it has "magic"
compression thanks to quenching. So I think that perhaps the Carnot
cycle efficiency might be being over applied to all heat engines i.e.
ones which are not Carnot engines.

Rather than magic, it sounds more like you don't know what quenching
actually is and does.

Post by Dave
The efficiency also isn't demonstrated as being really any different
from using steam, e.g. 101C with steam, to not using steam e.g. 99C at 1
ATM. I'm not suggesting that higher temperatures aren't more efficient,
just that the gains might not be worth all the extra cost, mass, effort,
and risk of high pressure, high temperature steam.

324 years of use and actual experience says you are pissing in the wind.

In medieval times they knew how to build well insulated houses: thatched
roofs, straw and muck walls. Then after the Napoleonic Wars houses
became a lot more rubbish, likely to keep miners busy and stop them
revolting. or having to fix up another European War.

Also high pressure steam was quite a challenge, same as the biggest
possible wind turbines today.

Understand that zero carbon changes everything. With reliable 250W
generation 365/24/7, together with composted biomass and managed passive
solar, energy import for my suburban house goes to zero. Bye bye grid
and gas network.

You are right that there is no government support for this. Socialism is
dependency culture.

Post by Jim Pennino
If your daydream were actual reality someone would have noticed long
ago.

[Jim Pennino]

Post by Dave

Post by Jim Pennino

Post by Dave
e = 1 - Tc/Th
In the Carnot cycle, there are some statements like "ideal gas".
However in the real world, steam is a not an ideal gas, it has "magic"
compression thanks to quenching. So I think that perhaps the Carnot
cycle efficiency might be being over applied to all heat engines i.e.
ones which are not Carnot engines.

Rather than magic, it sounds more like you don't know what quenching
actually is and does.

Post by Dave
The efficiency also isn't demonstrated as being really any different
from using steam, e.g. 101C with steam, to not using steam e.g. 99C at 1
ATM. I'm not suggesting that higher temperatures aren't more efficient,
just that the gains might not be worth all the extra cost, mass, effort,
and risk of high pressure, high temperature steam.

324 years of use and actual experience says you are pissing in the wind.

In medieval times they knew how to build well insulated houses: thatched
roofs, straw and muck walls. Then after the Napoleonic Wars houses
became a lot more rubbish, likely to keep miners busy and stop them
revolting. or having to fix up another European War.

Arm waving nonsense that has nothing to do with steam engines.

Post by Dave
Also high pressure steam was quite a challenge, same as the biggest
possible wind turbines today.

Utter nonsense that shows zero understanding of both history and science.

Post by Dave
Understand that zero carbon changes everything. With reliable 250W
generation 365/24/7, together with composted biomass and managed passive
solar, energy import for my suburban house goes to zero. Bye bye grid
and gas network.

Don't forget your batteries that will need replacing every few years.

Composted biomass is not zero carbon and is a major source of greenhouse
gases.

"managed passive solar" is a contradiction in terms; it is either
passive or managed, it can't be both at the same time.

Post by Dave
You are right that there is no government support for this. Socialism is
dependency culture.

Again, utter nonsense.

There has been massive government support for residential "green" energy
for decades now and the unintended consequences, such as the fact that
decades old solar panels containing toxid magerials in the millions now
need disposal, are coming home to roost.

Recycling is not the answer as recycling a solar panel costs $20 to $40
to do and you get $2 to $3 of usefull stuff.

[Dave]

Post by Dave

Post by Jim Pennino

e =  1 - Tc/Th
In the Carnot cycle, there are some statements like "ideal gas".
However in the real world, steam is a not an ideal gas, it has "magic"
compression thanks to quenching.  So I think that perhaps the Carnot
cycle efficiency might be being over applied to all heat engines i.e.
ones which are not Carnot engines.

Rather than magic, it sounds more like you don't know what quenching
actually is and does.

The efficiency also isn't demonstrated as being really any different
from using steam, e.g. 101C with steam, to not using steam e.g. 99C at 1
ATM.  I'm not suggesting that higher temperatures aren't more efficient,
just that the gains might not be worth all the extra cost, mass, effort,
and risk of high pressure, high temperature steam.

324 years of use and actual experience says you are pissing in the wind.

In medieval times they knew how to build well insulated houses: thatched
roofs, straw and muck walls.  Then after the Napoleonic Wars houses
became a lot more rubbish, likely to keep miners busy and stop them
revolting. or having to fix up another European War.
Also high pressure steam was quite a challenge, same as the biggest
possible wind turbines today.
Understand that zero carbon changes everything. With reliable 250W
generation 365/24/7, together with composted biomass and managed passive
solar, energy import for my suburban house goes to zero. Bye bye grid
and gas network.
You are right that there is no government support for this. Socialism is
dependency culture.

There can be reasons why technology is buried. e.g. In the Napoleonic
Wars it is likely came up with a still classified steam flechette
(crossbow bolt) machine to fire 2x 4 ounce bolts accurate to 600 yards,
operated by two people, one to load and one to aim, all powered by tank
of hot water, with two gallons lasting half an hour (3600 rounds).

Post by Dave

Post by Jim Pennino
If your daydream were actual reality someone would have noticed long
ago.

[Jim Pennino]

In sci.physics Dave <***@yahoo.com> wrote:

<snip old crap>

Post by Dave
There can be reasons why technology is buried.

A childish supposition.

Post by Dave
e.g. In the Napoleonic
Wars it is likely came up with a still classified steam flechette
(crossbow bolt) machine to fire 2x 4 ounce bolts accurate to 600 yards,
operated by two people, one to load and one to aim, all powered by tank
of hot water, with two gallons lasting half an hour (3600 rounds).

Idiotic nonsense on so many levels.

Did you read about this in a comic book?

[Clutterfreak]

In the Napoleonic Wars it is likely came up with a still
classified steam flechette (crossbow bolt) machine to fire 2x 4
ounce bolts accurate to 600 yards, operated by two people, one to
load and one to aim, all powered by tank of hot water, with two
gallons lasting half an hour (3600 rounds).

That would require compressing about 2.5 liters of steam (at STP)
to throw 2 bolts of 4 ounces each.

Now if I knew what the compression rate in an air-gun is, I'd be
able to estimate and say if the above was any feasible and under
what conditions :)

[Dave]

Post by Jim Pennino

e =  1 - Tc/Th
In the Carnot cycle, there are some statements like "ideal gas".
However in the real world, steam is a not an ideal gas, it has "magic"
compression thanks to quenching.  So I think that perhaps the Carnot
cycle efficiency might be being over applied to all heat engines i.e.
ones which are not Carnot engines.

Rather than magic, it sounds more like you don't know what quenching
actually is and does.

The efficiency also isn't demonstrated as being really any different
from using steam, e.g. 101C with steam, to not using steam e.g. 99C at 1
ATM.  I'm not suggesting that higher temperatures aren't more efficient,
just that the gains might not be worth all the extra cost, mass, effort,
and risk of high pressure, high temperature steam.

324 years of use and actual experience says you are pissing in the wind.

thatched roofs, straw and muck walls.  Then after the Napoleonic Wars
houses became a lot more rubbish, likely to keep miners busy and stop
them revolting. or having to fix up another European War.
Also high pressure steam was quite a challenge, same as the biggest
possible wind turbines today.
Understand that zero carbon changes everything. With reliable 250W
generation 365/24/7, together with composted biomass and managed
passive solar, energy import for my suburban house goes to zero. Bye
bye grid and gas network.
You are right that there is no government support for this. Socialism
is dependency culture.

There can be reasons why technology is buried.  e.g. In the Napoleonic
Wars it is likely came up with a still classified steam flechette
(crossbow bolt) machine to fire 2x 4 ounce bolts accurate to 600 yards,
operated by two people, one to load and one to aim, all powered by tank
of hot water, with two gallons lasting half an hour (3600 rounds).

Post by Jim Pennino
If your daydream were actual reality someone would have noticed long
ago.

Unfortunately low pressure steam generated wouldn't be so good in
practice, because you'd only get steam generated at the very top, since
the pressure increases fast as you go down the water in the vessel. So
refrigerants would be needed, which isn't ideal. Either they are good
and get banned, or they seem to be flammable. Need one with a boiling
point of about 35 degrees in the UK. Much less and the day/night
average temperature could getting uncomfortably close to approaching this.

Noted a couple of things in the last couple of days. Ram pumps, i.e.
use water from a reservoir to pump water higher than it came from (late
18th century), and the first refrigerator was patented with R610 in 1834.

I can easily get 45 C water using unpressurised thermal ponds - pond
liner etc. However for 70C plus expect would need thermal tubes, much
less area, but higher temperature for the same money.

Also noted is the "glamour" of electricity generation compared to
insulation and passive solar. Same issues with fusion power. The hot
plasma is Midas gas, can you get the heat out or will it ruin everything
it touches? Pellet based laser fusion isn't any good either because
someone might try boosting the output by adding more fuel than the
design characteristics of the vessel is build to withstand.

[Dave]

e =  1 - Tc/Th
In the Carnot cycle, there are some statements like "ideal gas". However
in the real world, steam is a not an ideal gas, it has "magic"
compression thanks to quenching.  So I think that perhaps the Carnot
cycle efficiency might be being over applied to all heat engines i.e.
ones which are not Carnot engines.
The efficiency also isn't demonstrated as being really any different
from using steam, e.g. 101C with steam, to not using steam e.g. 99C at 1
ATM.  I'm not suggesting that higher temperatures aren't more efficient,
just that the gains might not be worth all the extra cost, mass, effort,
and risk of high pressure, high temperature steam.
I'm working though if work can be obtained from low pressure steam, with
pressure reduction from a head. Need to consider vapour pressure etc.
Even might get to use a N. Tesla one-way pipe/valve.

Seems like a Tesla valve would reduce the height needed (10m) for a
vacuum head. This is because the water would fall out from gravity, and
not be replaced by any air coming in. Plumbers know about vacuum and
suction in waste pipes (gurgling). Also when emptying a 2l light plastic
plastic bottle it compresses a bit then gurgles sucks the air in and the
emptying continues. 3m is a practical height, 5m maybe at a push, and
10m, no way without plans, construction, and building control. Need to
buy some one way pipe and see. Might not need a full vacuum, but
unfortunately the graph of boiling point against temperature isn't linear.

Want a low temperature distillation for no-electric atmospheric water
generation purpose. (capture with calcium chloride and distil).

[Jim Pennino]

In sci.physics Dave <***@yahoo.com> wrote:

<snip old crap irrelevant to this post>

Post by Dave
Seems like a Tesla valve would reduce the height needed (10m) for a
vacuum head.

Only to someone with a poor understanding of physics.

Post by Dave
This is because the water would fall out from gravity, and
not be replaced by any air coming in.

But will be replaced by water vapor.

Post by Dave
Plumbers know about vacuum and
suction in waste pipes (gurgling).

Waste pipes work using gravity flow, not suction.

Gurgling in a waste pipe is normally a sign of downstream blockage and
pressure.

Post by Dave
Also when emptying a 2l light plastic
plastic bottle it compresses a bit then gurgles sucks the air in and the
emptying continues. 3m is a practical height, 5m maybe at a push, and
10m, no way without plans, construction, and building control. Need to
buy some one way pipe and see. Might not need a full vacuum, but
unfortunately the graph of boiling point against temperature isn't linear.

The boiling point of water versus pressure has been well understood for
hundreds of years.

Post by Dave
Want a low temperature distillation for no-electric atmospheric water
generation purpose. (capture with calcium chloride and distil).

You do realize that calcium chloride will dissolve in its own water of
hydration and form a hard amalgamated solid unless it is heated very
slowly?