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| blackhead... |
 Posted: Sun Jul 05, 2009 1:29 pm |
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Googling "Converting methane to electricity" returns results that burn
it and then use the kinetic energy of the gas to drive a prime mover
of an electricity generator. As someone who's a complete incompetent
in this area, I would have thought that most generators using this
method will be around 30% efficient because the prime mover uses only
1 of the 3 components of momentum, so:
1. What techniques are used to get energy from the other 2 components?
3. Are there methods of using chemical reactions involving methane,
such as a methane battery cell, that are more efficient in extracting
energy from methane?
3. What is the most efficient way of extracting energy from methane?
Thanks in advance. |
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| blackhead... |
| Posted: Sun Jul 05, 2009 2:44 pm |
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On 6 July, 00:39, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net> wrote:
[quote:d6e584bedd]Dear blackhead:
"blackhead" <larryhar... at (no spam) softhome.net> wrote in message
news:df02170f-ec81-490c-be3d-e24d72078d2e at (no spam) y7g2000yqa.googlegroups.com...
Googling "Converting methane to electricity" returns
results that burn it and then use the kinetic energy
of the gas to drive a prime mover of an electricity
generator. As someone who's a complete
incompetent in this area, I would have thought that
most generators using this method will be around
30% efficient
Study "Carnot efficiency".
because the prime mover uses only 1 of the 3
components of momentum, so:
1. What techniques are used to get energy from
the other 2 components?
What do you imagine these other "two" components to be?
[/quote:d6e584bedd]
The other 2 orthogonal components of momentum. All engines I have seen
have a piston arrangement in one dimension and hence use just one
component of momentum to drive them.
[quote:d6e584bedd]3. Are there methods of using chemical
reactions involving methane, such as a
methane battery cell, that are more efficient
in extracting energy from methane?
No. Carbon is toxic to any efficient process.
3. What is the most efficient way of extracting
energy from methane?
Burn it.
David A. Smith[/quote:d6e584bedd] |
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| N:dlzc D:aol T:com (dlzc)... |
| Posted: Sun Jul 05, 2009 5:39 pm |
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Guest
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Dear blackhead:
"blackhead" <larryharson at (no spam) softhome.net> wrote in message
news:df02170f-ec81-490c-be3d-e24d72078d2e at (no spam) y7g2000yqa.googlegroups.com...
[quote:d4f2e5784e]Googling "Converting methane to electricity" returns
results that burn it and then use the kinetic energy
of the gas to drive a prime mover of an electricity
generator. As someone who's a complete
incompetent in this area, I would have thought that
most generators using this method will be around
30% efficient
[/quote:d4f2e5784e]
Study "Carnot efficiency".
[quote:d4f2e5784e]because the prime mover uses only 1 of the 3
components of momentum, so:
1. What techniques are used to get energy from
the other 2 components?
[/quote:d4f2e5784e]
What do you imagine these other "two" components to be?
[quote:d4f2e5784e]3. Are there methods of using chemical
reactions involving methane, such as a
methane battery cell, that are more efficient
in extracting energy from methane?
[/quote:d4f2e5784e]
No. Carbon is toxic to any efficient process.
[quote:d4f2e5784e]3. What is the most efficient way of extracting
energy from methane?
[/quote:d4f2e5784e]
Burn it.
David A. Smith |
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| Mark Thorson... |
| Posted: Sun Jul 05, 2009 7:35 pm |
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blackhead wrote:
[quote:157e7d1d77]
On 6 July, 00:39, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net> wrote:
"blackhead" <larryhar... at (no spam) softhome.net> wrote in message
because the prime mover uses only 1 of the 3
components of momentum, so:
1. What techniques are used to get energy from
the other 2 components?
What do you imagine these other "two" components to be?
The other 2 orthogonal components of momentum. All engines I have seen
have a piston arrangement in one dimension and hence use just one
component of momentum to drive them.
[/quote:157e7d1d77]
Never heard of a radial engine? That has an
arrangement of pistons in two dimensions driving
a central shaft. Most WW2 aircraft used radial
engines.
A three-dimensional arrangement is used to drive
a central sphere. We don't sell many of those. |
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| Charles... |
| Posted: Sun Jul 05, 2009 7:46 pm |
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On Sun, 05 Jul 2009 18:35:54 -0700, Mark Thorson <nospam at (no spam) sonic.net>
wrote:
[quote:84e6d96c89]blackhead wrote:
On 6 July, 00:39, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net> wrote:
"blackhead" <larryhar... at (no spam) softhome.net> wrote in message
because the prime mover uses only 1 of the 3
components of momentum, so:
1. What techniques are used to get energy from
the other 2 components?
What do you imagine these other "two" components to be?
The other 2 orthogonal components of momentum. All engines I have seen
have a piston arrangement in one dimension and hence use just one
component of momentum to drive them.
Never heard of a radial engine? That has an
arrangement of pistons in two dimensions driving
a central shaft. Most WW2 aircraft used radial
engines.
A three-dimensional arrangement is used to drive
a central sphere. We don't sell many of those.
[/quote:84e6d96c89]
What ever happened to the gentleman with the liquid piston engine? He
could probably sort this one out. |
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| N:dlzc D:aol T:com (dlzc)... |
| Posted: Sun Jul 05, 2009 8:43 pm |
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Guest
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Dear blackhead:
"blackhead" <larryharson at (no spam) softhome.net> wrote in message
news:40813831-401e-4e8a-9508-26d5ece32269 at (no spam) r33g2000yqn.googlegroups.com...
On 6 July, 00:39, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net>
wrote:
....
[quote:3d48022931]1. What techniques are used to get energy from
the other 2 components?
What do you imagine these other "two"
components to be?
The other 2 orthogonal components of momentum.
All engines I have seen have a piston arrangement
in one dimension and hence use just one
component of momentum to drive them.
[/quote:3d48022931]
No, they use momentum in all directions to achieve pressure,
which moves the piston and the mass of burning gases. And you
should become familiar with turbines, which use momentum in many
directions.
Not everything is like a pelton wheel.
http://en.wikipedia.org/wiki/Pelton_wheel
It is a simple matter to have a curved surface turn momentum in
another direction...
The efficiency limit is the carnot efficiency. The details only
keep you from achieving this, but will never allow you to exceed
it.
http://en.wikipedia.org/wiki/Carnot%27s_theorem_(thermodynamics)
David A. Smith |
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| blackhead... |
| Posted: Mon Jul 06, 2009 1:02 am |
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On 6 July, 03:43, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net> wrote:
[quote:99d59e3c09]Dear blackhead:
"blackhead" <larryhar... at (no spam) softhome.net> wrote in message
news:40813831-401e-4e8a-9508-26d5ece32269 at (no spam) r33g2000yqn.googlegroups.com...
On 6 July, 00:39, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net
wrote:
...
1. What techniques are used to get energy from
the other 2 components?
What do you imagine these other "two"
components to be?
The other 2 orthogonal components of momentum.
All engines I have seen have a piston arrangement
in one dimension and hence use just one
component of momentum to drive them.
No, they use momentum in all directions to achieve pressure,
which moves the piston and the mass of burning gases. And you
should become familiar with turbines, which use momentum in many
directions.
[/quote:99d59e3c09]
Only that component of the momentum normal to the surface of the
piston will move it, with the other 2 components of momentum remaining
unchanged and eventually giving up their energy as heat to the side
walls. As I see it, gas turbines are optimised for gas flow along the
axis of the turbine and hence momentum in one direction only.
[quote:99d59e3c09]Not everything is like a pelton wheel.http://en.wikipedia.org/wiki/Pelton_wheel
It is a simple matter to have a curved surface turn momentum in
another direction...
The efficiency limit is the carnot efficiency. The details only
keep you from achieving this, but will never allow you to exceed
it.http://en.wikipedia.org/wiki/Carnot%27s_theorem_(thermodynamics)
David A. Smith[/quote:99d59e3c09] |
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| dlzc... |
| Posted: Mon Jul 06, 2009 4:11 am |
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Dear blackhead:
On Jul 6, 4:02 am, blackhead <larryhar... at (no spam) softhome.net> wrote:
[quote:3f02e0aa25]On 6 July, 03:43, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net> wrote:
"blackhead" <larryhar... at (no spam) softhome.net> wrote in message
news:40813831-401e-4e8a-9508-26d5ece32269 at (no spam) r33g2000yqn.googlegroups.com....
On 6 July, 00:39, "N:dlzc D:aol T:com \(dlzc\)" <dl... at (no spam) cox.net
wrote:
...
1. What techniques are used to get energy from
the other 2 components?
What do you imagine these other "two"
components to be?
The other 2 orthogonal components of momentum.
All engines I have seen have a piston arrangement
in one dimension and hence use just one
component of momentum to drive them.
No, they use momentum in all directions to
achieve pressure, which moves the piston and
the mass of burning gases. And you should
become familiar with turbines, which use
momentum in many directions.
Only that component of the momentum normal
to the surface of the piston will move it,
[/quote:3f02e0aa25]
What moves the mass of the gas along with the piston? What maintains
the pressure, while not dispersing the momentum in the other
directions? That "other 2 components" is not lost, because the piston
walls do not expand also. So consequently all that momentum is
converted and used.
[quote:3f02e0aa25]with the other 2 components of momentum
remaining unchanged
[/quote:3f02e0aa25]
No, they are *not* unchanged.
[quote:3f02e0aa25]and eventually giving up their energy as heat
to the side walls.
[/quote:3f02e0aa25]
No. Momentum is *always* conserved, only *energy* is lost. The
momentum all goes two places, moving the piston, and moving the gas
out the exhaust ports.
[quote:3f02e0aa25]As I see it, gas turbines are optimised for
gas flow along the axis of the turbine and
hence momentum in one direction only.
[/quote:3f02e0aa25]
Then you'd better get your eyes checked. You seem to stubbornly
refuse to accept anything new with grace.
Now are you satisfied about your root question regarding methane?
David A. Smith |
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| Salmon Egg... |
| Posted: Mon Jul 06, 2009 6:14 am |
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Guest
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In article
<545b333b-68d1-45c3-9a4d-1166969c826d at (no spam) h18g2000yqj.googlegroups.com>,
blackhead <larryharson at (no spam) softhome.net> wrote:
[quote:dfd591c023]Only that component of the momentum normal to the surface of the
piston will move it, with the other 2 components of momentum remaining
unchanged and eventually giving up their energy as heat to the side
walls. As I see it, gas turbines are optimised for gas flow along the
axis of the turbine and hence momentum in one direction only.
[/quote:dfd591c023]
This one instance where a little knowledge screws up overall thinking.
In a piston engine only the linear moment component normal to the piston
face is used. The mechanical energy absorbed by the piston reduces the
temperature of the working fluid. To the extent that there is thermal
equilibrium during the process, collisions among the molecules randomize
the motions of them so that the normal component of momentum is quickly
replenished. Remember that most molecules are not in contact with the
piston.
Bill
--
Most people go to college to get their missing high school education. |
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