The
contradiction with Carnot’s principle is analyzed.
The absence of necessary
work to deliver in the process can be easily explained by the fact that
each molecule is accelerated when it arrives on the plate, then slowed
down with the same value of energy when it bounces back. W1-
W2 = 0. The electric field doesn’t provide the molecules withenergy
that it cannot recover. The energy is continually given and recovered
from the gas molecules when they go to and fro between the plates.
Advantages
of the invention compared to the existing pumps
The advantages of this invention are those of the thermoelectric pumps:
compactness, simplicity, no parts in motion, so no noise, and adding to
this, a very good coefficient of performance able to save energy and reduce
pollution ( Efficiency coefficient or coefficient of performance or COP
= ratio of the quantity of energy rejected at the warm source (in calories)
by the work delivered at the pump (in Joules. 1 calorie = 4.18 joules)
). See also in the applications, the new possibilities induced by this
coefficient of performance.
Why can the coefficient of performance of this process go beyond Carnot’s
? Comparison of The thermodynamic cycles.
Carnot’s
theorem :
|
According
to Carnot’s theorem, if one disposes of a cold source,
at 150 Kelvin and
a warm source at 300 K ( T warm source / T cold source = 2) and
takes off one calorie at the cold source, it induces a minimum
rejection of 2 calories at the warm source, the second calorie coming
from the minimum work delivered at the pump ( 4.18 joules). In that
case, Carnot’s COP = 2. To enlighten the cause of the
irreducible work to deliver in all the actual processes, it is necessary
to closely observe Carnot’s cycle which is a perfect method as far
as the minimum amount of work to deliver in a mechanical compression
heat pump is concerned.
|
Let’s consider a mole of perfect
gas at 150K
|
(1)
Adiabatic compression of the gas to reach the temperature of the
warm source.
(2)
After having been put in contact with the warm source, it
is compressed again in an isothermal way to pour heat
into it. This operation must be done very slowly not to overheat
the gas compared to the warm source.
(3)
Adiabatic expansion of the gas to cool it until it reaches the temperature
of the cold source.
(4)
After having been put in contact with the cold source, it is expanded
again in an isothermal way ( very slowly ) to draw heat from it.
|
We realize
that we reach about the same result by suppressing the compression and
the isothermal expansion and by replacing them by a slight difference
in temperature between the gas and the cold or warm source when they are
put in contact. This method brings us nearer from the thermodynamic cycle
of the invention and is going to show clearly the difference and originality
of the invention.
|
(1)
Adiabatic compression of the gas (1 mole) and warming up from 150
to 302 K (302 K is arbitrarily chosen).
W1 = 1895.66 Joules
with W= 3/2 R (T1 – T2)
(2)
Cooling of the gas after the contact with the warm source, from 302
to 300K.
Heat emitted dU=24.94 J (with
U= 3/2 RT).
(3)
Adiabatic expansion of the gas and down
from 300 to 149.0066K
W2 = 1883.11 Joules . Now
the temperature of 149.0066K is determined by the ratio of the volumes
V1/V2, identical in the compression and the
expansion.
with T2= (V1/V2)2/3xT1
and V2 = V1/ (T2 /T1)3/2
(4)
Warming up of the gas in contact with the cold source from 149.0066K
to 150K. Heat received: 12.39 Joules.
|
One can
sum up the situation with the energetic cycle represented below: If one
takes 12.39 Joules at the cold source,
29.94 Joules are rejected at the warm source, that is to say a difference
of 12.55 J which corresponds exactly to the work globally spent in the
cycle (w1-w2).
As foreseen,
1 calorie taken at the cold source induces the rejection of 2 calories
at the warm source ( 24.94/12.39=2.013). The second calorie coming from
the work delivered.
One can
see that the gas energy, that is to say its temperature, is on average
higher during the compression than during the expansion, simply because
it is warmed up just before the compression stage and cooled down just
before the expansion stage. Yet, if the gas is warmer during the compression,
its pressure is also higher. Consequently the compression work W1
is inevitably more important than the expansion work W2, hence
a global irreducible work to deliver. ( i.e.: 12.55J).
(1)
Acceleration or warming up of the gas molecule
in the attraction field.
(2)
Cooling by thermal accommodation.
(3)
Slowing down or cooling of the molecule
in the attraction field.
(4)
Warming up by thermal accommodation.
|
The
work of the piston in Carnot cycle is replaced here by the work of the
attraction field and the contact with the cold or warm source in Carnot
cycle is done here by thermal accommodation. But, while in Carnot cycle
the necessary compression work to warm up the gas (w1) was
superior to the expansion work (w2) which was cooling it down,
this time the attraction field accelerates then slows down the molecule
according to the same potential energy. W1 – W2=
0
|
To enlighten
this angle, one could compare the molecule which falls on the plate
to a ball in space which falls on a planet ( one must assume that
there is no atmosphere and that the ball has a very high initial
speed). When it penetrates into the gravitational field of the planet,
the ball is accelerated. Because of the shock, it yields energy
in the shape of heat and so rebounds at a lower speed. When it goes
up again, it slows down and goes back into space with a kinetic
energy lower than the one it had before falling on the planet. Its
energetic curve would exactly corresponds to the one described in
the one described in the left part of the diagram above.
|
Once
out of the gravitational field, the ball has no energetic debt owed to
the gravitational field. The later accelerates the ball when it falls
down but it slows down as much when it goes up again. The principle of
conservation of energy is respected. The energy freed during the shock
is paid by a final slowing down of the ball but absolutely not by the
gravitational field. It is the same for a molecule in the electrostatic
attraction field.
|
One can be persuaded of it by observing the experiment of the blade
which is introduced in the condenser. To have a more vivid imagery,
we can replace the blade by a ball which would roll on a horizontal
plane as represented on the diagram opposite. By penetrating into
the electric field of the condenser, the ball accelerates, its kinetic
energy increases of a value corresponding to the attraction energy
of the ball, it strikes the rebound plate by yielding energy and
so goes back at a lower speed, then it slows down when going out
ft the electric field of the condenser. During this operation, if
the condenser is maintained at a constant charge (and not at a constant
potential), there is no loss of electric energy with a perfect electric
insulation. It is exactly the same thing for the molecules in this
process.
It wasn’t
the same thing in Carnot cycle where the work done by the acceleration
of the molecules during the compression could in no case be totally
recovered by their deceleration during the expansion, the heat freed
at the warm source was partly paid in return by the work of the
piston.
To conclude: there is no longer necessarily a work to
provide which would be transformed into heat and rejected at the
warm source. In the case where the work is nil, each calorie taken
at the cold source is rejected at the warm source and nothing more.
We’ll see in the applications the consequences induced by this new
propriety.
|
|