U.S. patent number 3,902,549 [Application Number 05/301,131] was granted by the patent office on 1975-09-02 for method and apparatus for producing a temperature gradient in a substance capable of carrying thermal energy.
Invention is credited to Adolf Opfermann.
United States Patent |
3,902,549 |
Opfermann |
September 2, 1975 |
Method and apparatus for producing a temperature gradient in a
substance capable of carrying thermal energy
Abstract
A rotor is mounted for high-speed rotation. At its center is
located a source of thermal energy whereas at its periphery there
is located a heat exchanger. Chambers are provided, accommodating a
gaseous material which, depending upon its position in the
chambers, can receive heat from the source of thermal energy or
yield heat to the heat exchanger. The gas is subjected to a very
high acceleration and is moved from the region of the source of
thermal energy to the region of the heat exchanger; as a result of
this high acceleration a thermal or temperature gradient will be
established so that the gas will have a higher temperature on
contacting the heat exchanger to which it can then yield heat.
Inventors: |
Opfermann; Adolf (D-5038
Rodenkirchen near Cologne, DT) |
Family
ID: |
5823552 |
Appl.
No.: |
05/301,131 |
Filed: |
October 26, 1972 |
Foreign Application Priority Data
|
|
|
|
|
Oct 27, 1971 [DT] |
|
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2153539 |
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Current U.S.
Class: |
165/88;
165/104.25; 165/104.34 |
Current CPC
Class: |
F22B
27/12 (20130101); F24V 99/00 (20180501); F22B
3/06 (20130101); F28F 13/00 (20130101) |
Current International
Class: |
F22B
3/00 (20060101); F22B 3/06 (20060101); F22B
27/00 (20060101); F22B 27/12 (20060101); F24J
3/00 (20060101); F28d 011/08 () |
Field of
Search: |
;165/6,7,105,106,86,88,1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Sukalo; Charles
Attorney, Agent or Firm: Striker; Michael S.
Claims
What is claimed as new and desired to be protected by Letters
Patent is set forth in the appended:
1. In an apparatus for producing energy by establishing a
temperature gradient in a substance capable of carrying thermal
energy, a combination comprising a rotor having an outer
circumference and being mounted for rotation about an axis at
speeds capable of providing an acceleration of up to 500,000 g; a
stationary member for providing a source of thermal energy in the
region of said axis; a heat exchanger in the region of said outer
circumference for extracting useful heat energy from said
apparatus; a substance capable of carrying thermal energy; and
means defining in said rotor a path in which said substance is
confined and which extends from said source to said heat exchanger
whereby when said substance, having received an initial thermal
energy from said source, travels under the influence of centrifugal
force in said path to said heat exchanger, an upward thermal
gradient is established so that said substance can yield thermal
energy to said heat exchanger that is significantly greater than
said initial thermal energy.
2. A combination as defined in claim 1, wherein said stationary
member is a tube coaxial with said axis.
3. A combination as defined in claim 1, wherein said substance
comprises a noble gas.
4. A combination as defined in claim 1, said rotor having edge
faces having general planes which extend substantially normal to
said axis; and further comprising thermally insulating means at
said edge faces.
5. A combination as defined in claim 1, wherein said heat exchanger
is a radiant-heat exchanger.
6. A combination as defined in claim 1, further comprising
stationary evacuated chamber means surrounding said rotor, source
and heat exchanger; and conduit means connecting said source and
said heat exchanger with the exterior of said chamber means.
7. A combination as defined in claim 1, said rotor having a central
hollow hub coaxial with said axis and provided with an inner
circumferential surface; further comprising a plurality of annular
heat exchange fins provided on said surface; said means comprising
wall means forming a plurality of hollow radial spokes extending
from said hub to said outer circumference; and wherein said
substance is a gas accommodated in said spokes.
8. A combination as defined in claim 7, wherein said gas is
Xenon.
9. A combination as defined in claim 1, said means comprising a
plurality of pressure-resistant gas-tight tubes arranged
concentrically and with spacing from one another, said tubes having
respective ends which are sealed with thermally insulating
material; said substance being a gas accommodated under pressure in
said tubes; and wherein said heat exchanger comprises a plurality
of pipes surrounding said rotor.
10. A combination as defined in claim 1, said rotor comprising an
inner and an outer cylindrical rotor portion, and an annular rotor
portion interspersed between said inner and outer rotor portions
and being composed of material having at most poor electrical
conductivity characteristics.
11. A combination as defined in claim 1, wherein said source is a
heat exchanger, and heat exchange fluid circulates through the
same.
12. A combination as defined in claim 1, wherein said substance has
in liquid state good thermal but at most poor electrical
conductivity characteristics.
13. A combination as defined in claim 1, wherein said substance has
in gaseous state good thermal but at most poor electrical
conductivity characteristics.
14. A combination as defined in claim 1, wherein said substance has
in solid state good thermal but at most poor electrical
conductivity characteristics.
15. A combination as defined in claim 1, said rotor having opposite
axial ends; and further comprising thermally insulating means
provided at said opposite axial ends.
Description
BACKGROUND OF THE INVENTION
The present invention relates to the production of a temperature
gradient in a substance capable of carrying thermal energy, and
more particularly to a method and apparatus for carrying this into
effect.
The present invention is based on the realization that it is
impossible to economically extract energy from a medium, for
example water, which has a high thermal storage capacity, if the
medium is at a relatively low temperature. On the other hand, it is
possible to economically exploit the energy in such a medium if the
latter is available at a high temperature. Generally speaking, the
energy exploitation is the more advantageous, the greater the
temperature differential which is available.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to make it
possible to produce in a substance capable of carrying thermal
energy, hereafter called an energy carrier, a temperature
differential, in order to obtain a sufficiently large thermal
capacity which can be economically utilized.
Another object of the invention is to provide for the establishment
of such a temperature gradient which can be utilized in a user of
heat, or in a producer of coolness.
In keeping with these objects, and others which will become
apparent hereafter, one feature of the invention resides in a
method of producing a temperature gradient in a substance capable
of carrying thermal energy, such method comprising the steps of
providing a source of thermal energy, providing a heat exchanger to
which thermal energy is to be transferred, and establishing a path
between the source and the heat exchanger. A substance capable of
carrying thermal energy is confined in this path for transmission
of such energy from the source to the substance, and the latter is
then subjected to a very high acceleration whereby to effect
movement of the substance in the path, contact of the substance
with the heat exchanger, and simultaneously establish an upward
temperature gradient in the substance during movement of the same
towards the heat exchanger.
The acceleration is obtained by rotation, that is it is centrifugal
acceleration, and normally the rotation will be at uniform speed.
However, it is also possible to so regulate the rotation that a
strong but pulsing acceleration field is obtained.
The novel features which are considered as characteristic for the
invention are set forth in particular in the appended claims. The
invention itself, however, both as to its construction and its
method of operation, together with additonal objects and advantages
thereof, will be best understood from the following description of
specific embodiments when read in connection with the accompanying
drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a fragmentary section through an apparatus for carrying
out the present invention;
FIGS. 2a, 2b and 2c are three diagrammatic sketches illustrating
the operation of the apparatus of FIG. 1;
FIG. 3 is a view analogous to FIG. 2 but illustrating a further
embodiment of the invention;
FIG. 4 is similar to FIG. 3 illustrating an additional embodiment
of the invention; and
FIG. 5 is an axial section through still another embodiment of the
invention.
THEORETICAL CONSIDERATIONS BEHIND THE PRESENT INVENTION
Before discussing the drawing in detail, it is believed advisable
to first discuss the theoretical considerations which are behind
the present invention. The invention is based upon the realization
that it is possible to obtain economically utilizable thermal
energy by exploiting the temperature gradient which is called into
being in solids, liquids and gases capable of carrying thermal
energy, hereafter identified as energy carriers, when they are
subjected to strong acceleration.
For explanation it will be assumed that a gas is accommodated in a
completely thermally insulated vertical tube, which can be
maintained in thermal equilibrium and at constant temperature by a
thermostat which is advantageously located at the lower end of the
tube. It will further be assumed that a source of thermal energy is
arranged at the lower end of the tube and controlled by the
thermostat.
It will be apparent that gas molecules of the gas in the tube will
progressively lose energy of motion the farther they move upwardly
away from the source of thermal energy, because due to the
influence of gravitation they are forced to expend some of their
energy in moving away from the center of the gravitational field.
On the other hand, if a gas particle moves in opposite direction,
that is follows the direction of gravitational attraction, then it
undergoes an acceleration, that is an increase in its speed. The
development of an equilibrium in such an arrangement is a very slow
process, because gases are poor thermal conductors. The average
molecular speed v in gases having a mass M per gas molecule can be
calculated at a certain temperature T in accordance with the
following formula which is found in Euckenwicke, "Grundriss der
physikalischen Chemie", 1959, page 28: ##EQU1##
A gas molecule, which in principle is a freely moving body, would
completely lose its speed within v/g sec., as it moves vertically
upwardly in the aforementioned tube. The height to which is rises
is designated with s and can be derived as follows: ##EQU2##
During this distance s the gas molecule passes through a
temperature range from T-O and s/T is that distance over which the
gas molecule (considered with reference to the mean) loses a degree
of temperature, because the temperature is proportional to the
internal energy of the gas. It must be taken into account that a
gas can be and must be considered as a three-dimensional structure,
and that a noble gas has three energy-carrying degrees of freedom.
Nevertheless, no other formula for the temperature decrease exists
because all gas molecules are subjected to gravitational force. If
a molecule is considered which has received a horizontal impulse,
then it will be seen that it will move in a path which is
downwardly curved under the influence of gravitation, that is a
path having a downward component of movement, as a result of which
a downward impulse is transmitted for instance to an adjacent
rising molecule. In the end result the sum of the kinetic energy
and the positional energy is maintained on average. Thus, for gases
having more than three degrees of freedom greater heights of rise
will be found, and it will be found that their molecules rise over
longer distances per degree of temperature loss. If the number of
degrees of freedom is designated with F, then a formula is obtained
for the rising distance x per degree of temperature: ##EQU3##
From the above formula it is possible to determine that a
utilization of the gravitational field for energy production is
impossible, because the temperature gradient caused by the
gravitational field would be established very slowly and a device
for exploiting this would have to be extremely large.
The circumstances are different, however, where strong acceleration
fields act, for instance acceleration which has been caused by
high-speed centrifuges, where the establishment of a temperature
gradient can be effected in small or very small spaces. It can be
calculated that with the noble gas Xenon, for instance, it is
possible to obtain over a distance of only 1 cm. a temperature
gradient of 506.degree.C. if it is assumed that a centrifugal
acceleration of 500,000 g can be obtained. Of course, the question
arises whether this temperature differential, that is this
temperature gradient thus obtained, is not obtained at the expense
of exteriorly supplied energy. Naturally, energy must be employed
in order to start up the centrifuge. However, this requires only a
single expenditure of energy on the whole, if it is assured that
during the operation a minimum of frictional energy loss will
occur, for instance if the centrifuge is accommodated in a vacuum
chamber. Despite the high temperature gradient which will develop,
no heat transportation occurs if the gas space in question is
thermally insulated, as soon as an equilibrium has been obtain.
If one considers a gas molecule in this equilibrium condition,
which molecule movws upwardly and downwardly while travelling
radially in a radial tube, then this gas molecule will on the
average rise by a distance equal to a distance to which it has
previously descended. If heat is axially supplied, that is if
energy is applied in the form of heat, and if radial cooling is
effected, meaning that thermal energy is withdrawn, then the
molecule will no longer rise as high as it had previously descended
and it will therefore not fully yield the previously accepted
energy. This means that in order to reestablish the desired
equilibrium, energy must be supplied from the exterior of the
system. If, however, sufficient heat is supplied axially to
compensate for the amount of heat removed at the outer
circumference of the centrifuge by heat exchanger, then in effect a
quasi-stationary condition will develop. If, under such
circumstances, one follows the motion of molecule which is moving
in radially outward direction, then it will be seen that the
molecule will find the same temperature at the radially outer end
of its path which has caused it to rise. Thus, the molecule will
always reach the same height. However, it will have arrived at the
radially outer end of its path with a speed which is sufficient for
a greater rise than the one it has achieved, resulting from the
axially supplied thermal energy. The excess of speed will, however,
be reduced again by heat exchange at the outer circumference if the
centrifuge, that is at the outer end of the molecule path.
If one now considers the formula initially given for the
calculation of the average molecular speed v of gases having a mass
T per gas molecule, it will be seen that T can be calculated as
follows: ##EQU4##
The speed v after a descent through a distance of one centimeter at
an acceleration of 5 million m/sec. can be calculated and will be
found to be 316.23 m/sec. Thus, T = 4.0109M. Actually, this is true
only for single-atom gases, such as noble gases and metal
vapors.
Because the temperature is directly proportional to the energy of
movement, the value of T must be reduced in accordance with the
number of degrees of freedom to which the energy produced by the
descent is distributed. This is obtained by multiplying with the
factor 3/F, wherein F designates the number of degrees of freedom.
Because the heat capacity C.sub.v of a gas can be considered to be
directly proportional to the number of degrees of freedom of the
gas, this can be written as follows: ##EQU5##
This also takes abnormalities into account, namely if C.sub.v is
not equal to the number of degrees of freedom. The value of 2.98 is
indicative of the heat capacity C.sub.v for argon and helium.
Because a gas at least three degrees of freedom, it is possible to
replace the factor 3 with the factor 2.98 and the resulting formula
will be: ##EQU6##
In this connection it is pointed out that it is permissible, as
done in the present instance, to use the speed increase beginning
from rest position as a measure of temperature increase, because
proportionality with the energy content exists. Furthermore, on
descent the energy increase is dependent upon the distance of
descent, independently of the speed at which the body, for instance
the gas molecule, travels over this distance.
Thus, the following values can be calculated:
Xenon M = 131.3 C.sub.v = 2.98 Temperature Increase 526.6.degree.K
(Kelvin) Krypton M = 83.8 C.sub.v = 2.98 " " 336.1.degree.K Argon M
= 39.948 C.sub.v = 2.98 " " 160.degree. K Neon M = 20.183 C.sub.v =
2.98 " " 80.95.degree.K Helium M = 4.0026 C.sub.v = 2.98 " "
16.05.degree.K Chlorine M = 70.906 C.sub.v = 6.216 " "
136.3.degree.K Oxygen M = 31.998 C.sub.v = 5.034 " " 76.15.degree.K
Air M = 28.96 C.sub.v = 4.966 " " 69.26.degree.K Nitrogen M =
28.0134 C.sub.v = 4.971 " " 67.36.degree.K Carbon Dioxide M = 28.01
C.sub.v = 6.938 " " 48.25.degree.K Hydrogen M = 2.0159 C.sub.v =
4.905 " " 4.91.degree.K Electron M = 1/1200 " "
0.00334.degree.K
The above table gives information for gases, but analogous
considerations obtain with respect to liquids and solids.
It is still necessary to point out that adiabatic increases and
descents will lead to quasi-stationary conditions, even with
intended heat throughput, in which a mean distribution condition of
the gas masses in radial direction is obtained. This is not only
unavoidable, but in fact even desired, because such conditions make
possible a much more substantial heat transport than in gas masses
which are known as excellent thermal insulators. Thus, measures
should be taken to favor the rises and descents of this type, or
otherwise to assure movement of the gases.
If one now considers an energy carrier, that is a carrier of
thermal energy, be it in a form of a one-atomic or multi-atomic
gases, a liquid or a solid, then the atoms or molecules will
perform a microscopic movement. The amount of such movements is a
measure for the temperature of the energy carrier. If on these
irregular movements a radially directed strong acceleration is
superimposed, then all radially outwardly directed components of
movement will correspondingly strengthen and by influencing one
another there will be a corresponding temperature increase in
radial direction. This condition can now have superimposed a heat
flow, also in radial direction from inwardly towards outwardly,
because at the point of the high temperature heat can be
withdrawn.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Having thus discussed the theoretical considerations, reference
will now be made to the drawing in general, and in particular to
the embodiment illustrated in FIGS. 1 and 2.
The embodiment in FIGS. 1 and 2 serves to produce a radial
temperature gradient, a temperature increase, by producing a strong
acceleration field in form of centrifugal force. In the interior of
a rotor which will subsequently be discussed in detail, there is
provided a stationary tube 1 which is coaxial with the axis of
rotation of the rotor and is provided at its ends with connections
for the inflow and outflow of a medium flowing through the tube 1
and providing a source of thermal energy. This medium may be river
water or ocean water, by way of example. The inner circumferential
surface of the tube is provided for purposes of improved heat
exchange with radial fins 1a. The outer wall of the tube 1 is
provided with a plurality of discs 1b which extend radial and
normal to the axis of rotation of the rotor and are spaced on the
tube axially distanced from one another at equal dimensions.
Additional discs or lamellas 2b always extend between two adjacent
ones of the discs 1b without, however, contacting them; the discs
2b are mounted on the inner circumferential surface of an inner
tube 2 of the rotor itself. The inner tube is turnably journaled at
is opposite axial ends and carries on its outer periphery a
plurality of gas compartments which are of strong material and
extend radially outwardly. It will be appreciated that these gas
compartments must be so arranged that during rotation the rotor
will be in dynamic equilibrium. The number of compartments 3 should
be as great as possible and their radially extending side walls 3a
are of material which has good thermally insulating properties. The
inner and outer part-cylindrical walls 3b and 3c are of material
which has good heat-conductive properties.
To obtain gas circulation in the region of the colder portion of
the respective compartment 3, that is the one closer to the tube 2,
an insulating tube 4 may be provided which communicates with a
nozzle 4a and is provided at its other end with insulation 14. The
compartments 3 are surrounded at the exterior of the rotor by a
heat exchanger, for instance in form of fins 5 which serve to
withdraw heat at high temperature. Advantageously, the rotor will
be mounted in a stationary vacuum chamber 6 in which a high vacuum
is produced. However, although the vacuum chamber encloses the
entire rotor it leaves the interior of the tube 1 free, that is the
interior of the tube 1 will not be under vacuum.
Heat exchange can be effected via radiation to the lamellas or
fins, and from there via non-illustrated cooling elements through
which a heat exchange liquid can flow. However, it is also possible
to provide at the outer circumference of the rotor solder
connections of a large number of thermal elements which rotate with
the rotor, and the latter can then be configurated with the housing
as a collector-less direct current motor. In any case, it is
advantageous that for the hot components of the thermal elements to
be provided with thermal insulation in outward direction, and for
the cold components and solder connections of the thermal elements
to be located in the radially inner end portions of the
compartments 3.
The table given earlier indicates clearly that it is advisable to
use as the energy carrier in the chambers 3 a heavy noble gas or
gas mixture. Because heavy noble gases have poor thermally
conductive properties, especially at the low temperatures which are
desired in the region towards the tube 2, it is advisable to
compensate for this by a strong pressure increase, that is by
strongly pressurizing the compartments 3. In addition, it is
possible to provide agitating devices which agitate the cold gas
layers in order to prevent the strongly heat-insulating effect
exerted by stationary cold gas layers.
The supply of heat at the inner portion of the rotor and the
removal heat at the outer portion thereof, as well as the various
dimensions must be so accommodated to one another that no
unacceptable stresses will be obtained. If, instance, the rotor is
to provide an acceleration of approximately 500,000 g and the rotor
has a radius of 6 cm., with xenon being the energy-carrying gas,
then between the inner and outer ends of each compartment 3 there
will be established a temperature differential (at equilibrium) of
3000.degree. Kelvin. In other words, a temperature differential or
gradient of this magnitude will be produced, and it will be
advantageous for example to have the temperature of the gas be at
150.degree.K at the inner end of the compartment and at
3150.degree.K at the outer end. If at the inner end heat is
supplied by the source of heat to increase the temperature of the
gas from 150.degree. to 200.degree.K, and if heat is removed at the
outer end of the chamber to decrease from 3150.degree. to
800.degree.K, then this would result in a deviation from
equilibrium by 2400.degree.K, meaning that for each centimeter of
radial length of the compartment 3,400.degree.K will be available
for exploitation.
These conditions are obtained if the gas used as the energy carrier
is xenon. Of course, it is possible to use gas mixtures instead of
xenon, for instance a mixture of a heavier gas and a ligher gas. In
this case the lighter gas provides for a better contact with the
colder end of the compartment 3 and also has advantages because of
its higher thermal conductivity in this region. This makes it
possible to reduce the pressure at which the compartments 3 must be
kept.
If the construction is such that thermal transference is obtained
by radiation, then in the appropriate temperature region it is
possible to transmit a very high amount of thermal energy in a very
advantageous manner. If radiation from a square meter of surface
takes place at a temperature of 300.degree.K to a similarly
dimensioned surface at a temperature of 250.degree.K, an amount of
thermal energy is transmitted which corresponds approximately to
1.6 kilowatt of energy. Furthermore, one square meter of metal
surface can extract from a liquid whose temperature is higher by
50.degree.K, an amount of thermal energy corresponding to
approximately 60 kilowatt. A further increase at identical surface
area and temperature difference, employing the condensation of
vapors, can produce heat transfer equal to approximately 210
kilowatt of energy. Even low-boiling liquids such as ammonia or
ethane have strong heat of vaporization.
In FIGS. 2a, 2b and 2c I have illustrated the behavior of a gas
molecule in one of the chambers 3 of the embodiment in FIG. 1. The
direction of rotation of chamber 3 with the tube 2 is indicated by
the arrow 7.
FIG. 2a illustrates the behavior of a gas molecule when the final
speed of rotation has been reached, that is when the rotor has come
up to speed. In the narrow compartment 3 the molecule is
accelerated in radially outward direction by the wall 3b, impinges
upon the wall 3c and during a rise returns at the same speed to the
original height, that is the starting position.
FIG. 2 shows how the molecule behaves when it begins to cool at the
wall 3c of the compartment 3. It will be seen that due to the
cooling it loses speed and can no longer reach its starting
position. Therefore, it cannot fully yield the energy which it has
received during the fall in outward direction, it is during the
accelerated movement from the wall 3b towards the wall 3c, and thus
energy must be supplied.
FIG. 2c illustrates a quasi-stationary condition after an
equilibrium between the supply of energy at the inner end of the
chambers 3 rear the wall 3b, and cooling at the outer wall 3c has
been achieved. The gas molecule arrives at the wall 3c at an
increased speed from the starting position which is lowered or
decreased with respect to FIG. 2a, but because of the cooling at
the wall 3c it will reach only its previous position. The force
received is higher during the accelerated movement outwardly due to
the higher speed, but lasts for a correspondingly shorter time, so
that the two impulses in the two successive directions of movement
will be equal and opposite.
Coming now to the embodiment of FIG. 3 it will be seen that here
the rotor is designated with reference numeral 8, surrounding a
stationary tube 9 having radially inwardly extending fins 9a. The
tube 9 corresponds to the tube 1 of FIG. 1 and serves the same
purpose.
The rotor 8 is accommodated in a vacuum chamber 10 which is also
stationary and connected at least at one side with the tube 9
rigidly. The rotor 8 in this embodiment is composed of a plurality
of concentrically arranged pressure-tight tubes 8a, 8b, 8c and 8d
the ends of which are closed by thermally insulating material and
connected with one another. The tube 9 extends through opposite
walls of the chamber 10 and a heat-supplying medium, for instance
ambient air, ocean water or river water, can be circulated through
this tube which has good thermally conductive properties, and
especially has a good heat-radiating outer surface.
To obtain the maximum benefit of thermal transmission the inner
surface of the inner tube 8d of the rotor is blackened, as well as
the outer surface of the outer tube 8a. Intermediate of the tubes
8a, 8b, 8c and 8d are obtained completely closed annular gas
compartments 8e, 8f and 8g of which the inner chamber or
compartment 8g can be pressurized very high whereas the
successively outer compartments may be subjected to lesser internal
gas pressure. The compartments, which contain a gas as the energy
carrier, may also be provided interiorly with thin silvered foils
or sheet 8h, which have many pores so that they do not have to
withstand gas pressure during rotation.
Between the rotor 8 and the chamber 10 there are provided many
stationary tubes 11 extending in axial parallelism with the rotor
and connected together to form a system through which a heat
exchange medium can flow. Each of the tubes 11 is advantageously
blackened on its inwardly directed semi-cylindrical outer surface
portion 11a, whereas on the other outwardly directed
semi-cylindrical surface portion 11b it will advantageously be
silvered.
The operation of the device in FIG. 3 will be already understood.
When the rotor 8 is rotated at high speed, then a strong
temperature gradient will develop in the compartments 8e, 8f and
8g, which on the one hand will be dependent upon the speed of
rotation and on the other hand dependent upon the type of gas
enclosed in the compartments. Thermal energy is withdrawn from the
tube 9 by radiation and is yielded from the outer surface of the
tube 8 again by radiation to the tubes 8 which are connected with
the user, for instance a steam engine, a steam turbine or a gas
turbine. The working medium which circulates through the tubes 11
can advantageously be pre-cooled after it leaves the respective
user, the cooling being effected by contact with the medium passing
through the inner tube 9 before the latter enters into the tube 9.
Thus, the thermal differential which cannot be utilized in the user
itself, can be exploited and recovered. A transmission by radiation
is substantially faster than the development of a thermal gradient,
and the purpose of the mirrored surfaces mentioned earlier, which
may also be provided at other appropriate locations, are intended
to prevent a deterioration of the thermal gradient.
In FIG. 4 I have illustrated still another embodiment of the
apparatus which is reminiscent with the apparatus of FIG. 3. The
inner tube 12 corresponds to the tube 9 of FIG. 3, the vacuum
chamber 13 corresponds to the vacuum chamber 10 of FIG. 3 and the
tubes 14 correspond to the tubes 11 of FIG. 3.
In FIG. 4 the rotor 15 is provided with a turnably journalled
driven hollow shaft 15a the inner surface of which is blackened.
Exteriorly the shaft 15a is surrounded by a ring 15b which is
fixedly connected with it and constituted with electrically
non-conductive material. It is held together exteriorly by a metal
ring 15c and reinforced by one or more shrink-fitted metal rings
15d. The outer metal ring 15d is also blackened on its outer
surface, as well as the inwardly facing semi-cylindrical outer
surface portions of the tubes 14. The outwardly facing
semi-cylindrical outer surface portions of the tubes 14 are
provided with a layer 14a of insulating material and the metal
rings of the rotor are advantageously insulated.
FIG. 5, finally, is an axial section through a further embodiment
of the invention which is essentially analogous to FIGS. 3 and 4.
The rotor is designated with reference numeral 17 and is
illustrated only diagrammatically because of its likeness to FIGS.
3 and 4. It surrounds the stationary inner tube 16 and is in turn
mounted in a vacuum chamber 18 which has at opposite sides openings
for inflow and outflow of the heat-supplying medium for the tube
16. The center portion of the tube 16 is fixedly connected with the
rotor 17 and turns with the same, bearings 19 and 20 (preferrably
ball bearings) being provided for journalling it with respect to
the adjacent laterally stationary tubular portions 16a and 16b.
Intermediate the portions 16 and 16a, and 16 and 16b, there are
provided sealing rings 21 and 22. The inner surface 16c of the tube
16 is advantageously provided with a thin coating, for instance of
teflon or the like. Tubes 23 and 24 for circulating a
heat-exchanging medium are provided between the rotor 17 and the
wall of the chamber 18.
A motor housing 25 is mounted in the chamber 18, being hollow and
receiving a cooling material which flows in and out via the
conduits 26 and 27. The motor 28 drives a pulley 29 which in turn
drives the rotor 17 via belts 30.
In the illustrated embodiments the inner tubes 1, 9 or 12 are so
configurated that it is possible to directly pass through them a
heat-yielding medium, for instance water. If a very large amount of
heat is to be supplied, the tubes can also be replaced with massive
shafts of material having good thermally conductive properties, and
these may be connected at one or both outer ends with appropriately
dimensioned heat exchangers through which heat is supplied into the
material of the shafts to be yielded from the same to the
respective rotors. It is also possible to use heat of vaporization
or heat of condensation for heat exchange purposes with such
constructions.
It will be understood that it is also possible to provide a closed
circulation of a medium, for instance a medium other than water,
with which heat is supplied to the center of the rotor. Such a
medium may for instance be a low-boiling liquid such as ammonia or
ethane whose boiling temperature can be adjusted in wide limits by
changing the pressure to which it is subjected. If a heat exchanger
is provided exteriorly of the rotor housing, the vapor of such a
medium can be supplied, for instance via a pump, into the inner
tube 1 or the like of the rotor, and this inner tube is provided
with fins or other means for increasing its surface in order to
provide for a maximum heat exchange efficiency. The steam has heat
removed from it by transference to the rotor as this was disclosed
before, to such an extent that the steam becomes converted into
condensate. This condensate is conducted externally of the rotor by
the centrifugal speed of the rotor into an annular heat exchanger
which is located externally of the rotor and turns with the same.
Such a heat exchanger will also have a very large surface area and
by operation of the rotor there will develop a strong heating of
the condensate and thus the formation of hot steam which can be
introduced into a user, for instance a turbine. Such a turbine can
then be used for driving other users. The turbine rotor itself can,
however, also be coupled with the rotor of the apparatus according
to the present invention, in which latter case the arrangement can
advantageously be used as a refrigerant apparatus. The cooled steam
leaving the apparatus, for instance a turbine, is again condensed
in a separate condensor or by recirculating it to a second heat
exchanger system with large surface area in the interior of the
tube 1 or the like. From here the condensate returns to the
initially described heat exchanger which can serve as a
refrigerant-producing device in such a manner that it receives heat
from the exterior, that is from the areas to be cooled, which
serves to convert the condensate in the interior of the heat
exchanger into steam so that the steam can again be
recirculated.
It will be understood that each of the elements described above, or
two or more together, may also find a useful application in other
types of constructions differing from the types described
above.
While the invention has been illustrated and described as embodied
in an apparatus for producing a thermal gradient, it is not
intended to be limited to the details shown, since various
modifications and structural changes may be made without departing
in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the
gist of the present invention that others can by applying current
knowledge readily adapt it for various applications without
omitting features that, from the standpoint of prior art, fairly
constitute essential characteristics of the generic or specific
aspects of this invention and, therefore, such adaptations should
and are intended to be comprehended within the meaning and range of
equivalence of the following claims.
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