U.S. patent application number 11/922270 was filed with the patent office on 2009-05-28 for combination thermo-electric and magnetic refrigeration system.
Invention is credited to Lei Chen, Mark R. Jaworowski, Xiaomei Yu.
Application Number | 20090133409 11/922270 |
Document ID | / |
Family ID | 37595411 |
Filed Date | 2009-05-28 |
United States Patent
Application |
20090133409 |
Kind Code |
A1 |
Chen; Lei ; et al. |
May 28, 2009 |
Combination Thermo-Electric and Magnetic Refrigeration System
Abstract
A refrigeration system has a compartment and a first cooling
device. The first cooling device cools the compartment and
generates a magnetic field. The refrigeration system also has a
second device. The second device uses the generated magnetic field
for additional cooling to the compartment.
Inventors: |
Chen; Lei; (South Windsor,
CT) ; Jaworowski; Mark R.; (Glastonbury, CT) ;
Yu; Xiaomei; (Glastonbury, CT) |
Correspondence
Address: |
OHLANDT, GREELEY, RUGGIERO & PERLE, LLP
ONE LANDMARK SQUARE, 10TH FLOOR
STAMFORD
CT
06901
US
|
Family ID: |
37595411 |
Appl. No.: |
11/922270 |
Filed: |
June 24, 2005 |
PCT Filed: |
June 24, 2005 |
PCT NO: |
PCT/US2005/022376 |
371 Date: |
December 13, 2007 |
Current U.S.
Class: |
62/3.6 |
Current CPC
Class: |
Y02B 30/66 20130101;
H01L 2924/0002 20130101; H01L 23/473 20130101; F25B 21/00 20130101;
Y02B 30/00 20130101; H01L 2924/0002 20130101; H01L 2924/00
20130101 |
Class at
Publication: |
62/3.6 |
International
Class: |
F25B 21/02 20060101
F25B021/02 |
Claims
1. A refrigeration system comprising: a compartment; a first
cooling device, said first cooling device cooling said compartment
and generating an magnetic field; and a second device, wherein said
second device uses said generated magnetic field for additional
cooling.
2. The refrigeration system of claim 1, wherein said first cooling
device has at least one thermoelectric element connected to a power
source.
3. The refrigeration system of claim 1, wherein said first cooling
device has a plurality of thermoelectric elements connected in
series to a power source.
4. The refrigeration system of claim 1, wherein said first cooling
device has a plurality of thermoelectric elements connected in
series to a power source, said plurality of thermoelectric elements
being wound in a cylindrical configuration.
5. The refrigeration system of claim 4, wherein said second device
comprises a rotating member, said rotating member having a channel,
said channel having a working fluid therein, said rotating member
having at least a portion being made from a material selected from
the group consisting of a paramagnetic material, a ferromagnetic
material, and any combinations thereof.
6. The refrigeration system of claim 5, wherein said magnetic field
has a first intensity at a first area and has a second intensity at
a second different area, wherein second device has said rotating
member rotates from said first area to said second area, wherein
said rotating member is disposed periodically in said magnetic
field for heat exchanging with said working fluid.
7. The refrigeration system of claim 4, wherein said second device
comprises a movable member, said movable member having a channel
therein, said channel having a working fluid therein, said moving
member having at least a portion being made from a material
selected from the group consisting of a paramagnetic material, a
ferromagnetic material, and any combinations thereof.
8. The refrigeration system of claim 7, wherein said magnetic field
has a first intensity at a first area and has a second intensity at
a second different area, wherein second device has said movable
member or said magnetic field moving relative to the other, wherein
said movable member is disposed periodically in said magnetic field
for communicating heat with said working fluid therein.
9. The refrigeration system of claim 4, wherein said second device
comprises a coil, said being disposed in said magnetic field, said
magnetic field inducing a current in said coil, said current for
powering at least said first device.
10. The refrigeration system of claim 4, wherein said first device
has a working fluid through a conduit, wherein said second device
comprises a plurality of fine magnetic particles, said plurality of
fine magnetic particles being disposed in said working fluid.
11. The refrigeration system of claim 10, wherein said first
cooling device has said plurality of thermoelectric elements
connected in series to said power source, said plurality of
thermoelectric elements being wound in said cylindrical
configuration and forming an interior path therethrough, and
wherein said working fluid in said conduit is disposed through said
interior path with said fine magnetic particles therein.
12. The refrigeration system of claim 11, wherein said plurality of
fine magnetic particles are suspended in said working fluid.
13. The refrigeration system of claim 12, wherein said plurality of
fine magnetic particles suspended in said working fluid, said
plurality of fine magnetic particles suitable to substantially not
adversely affect a flow rate of said working fluid.
14. The refrigeration system of claim 12, wherein said working
fluid comprises ethylene glycol.
15. A temperature control system comprising: a compartment; a first
cooling and heating device, said first cooling and heating device
cooling and/or heating said compartment and generating an magnetic
field as a waste energy; and a second magnetic device, wherein said
second magnetic device comprises a magnetic material, said magnetic
material periodically being introduced in a generated magnetic
field for recapturing said waste energy from said magnetic field
and using said waste energy to power the temperature control
system.
16. A refrigeration system comprising: a compartment; a first
cooling device, said first cooling device cooling said compartment
and generating an magnetic field; and a second magnetic
refrigerator, wherein said second magnetic refrigerator comprises a
magnetic material, said magnetic material periodically being
introduced in said generated magnetic field, wherein said second
magnetic refrigerator has a working fluid being thermally connected
to said second magnetic refrigerator, wherein said working fluid is
connected to said compartment for additional cooling.
17-18. (canceled)
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a temperature control for a
compartment. More particularly, the present invention relates to a
magnetic refrigeration system that uses a magnetic field generated
from a number of thermoelectric elements that are wound in a
configuration.
[0003] 2. Description of the Related Art
[0004] Temperature control systems for heating and cooling devices
are known in the art. Such known systems use a vapor compression
cycle to provide cooling. Typically the refrigerant in vapor phase
is pumped from the evaporator by a compressor. The refrigerant is
then compressed to a superheated vapor. The high-pressure gaseous
refrigerant that absorbs the heat is sent to a condenser. The
refrigerant vapor is condensed to high-pressure liquid by
transferring heat from the refrigerant to a heat sink that has
lower temperature. The condensed refrigerant liquid is circulated
to a throttling valve. The throttling valve reduces the pressure to
a low level and the refrigerant enters the evaporator. The reduced
pressure decreases the boiling temperature of the refrigerant to
below the temperature of the heat source. In the evaporator, the
evaporation of the low-pressure refrigerant absorbs heat from the
heat source that is cooled. Then the refrigerant is circulated to
the compressor to start the next refrigeration cycle. Due to the
complex mechanical operations associated with the vapor compression
cycle, the system response to varied demand is typically slow.
[0005] A thermoelectric device is also known and preferred over
other temperature control devices for the applications where
compactness and a quiet operation are needed. This thermoelectric
device avoids the use of any atmosphere destroying refrigerants and
is thus environmentally friendly. In one known configuration
thermoelectric devices are wound around, for example, a conduit.
The thermoelectric devices also provide both selective cooling
and/or heating around, and in the conduit.
[0006] However, a known problem in the art is that the one or more
thermoelectric devices generate a magnetic field. This magnetic
field is known in the art as being harmful to electronic
components. This magnetic field is also harmful for other reasons
and generally is disfavored. This magnetic field may disrupt the
operation of electrical systems and is typically shielded against
contacting an individual and/or components. Often, a manufacturer
will provide an amount of shielding in the system. This shielding
prevents the generated magnetic field from entering, penetrating or
contacting components or anything else located close by.
[0007] Accordingly, there is a need for a cooling system that
productively uses the generated magnetic field. There is also a
need for a cooling system that uses the magnetic field to provide
additional cooling and for a more productive operation of the
refrigeration system.
[0008] There is also a need for such a system that eliminates one
or more of the aforementioned drawbacks and deficiencies of the
prior art.
SUMMARY OF THE INVENTION
[0009] It is an object of the present invention to provide a system
for refrigeration.
[0010] It is another object of the present invention to provide a
system for refrigeration that uses a number of thermoelectric
devices and a magnetic field that is generated from the number of
thermoelectric devices.
[0011] It is yet another object of the present invention to provide
a system for refrigeration that uses a number of thermoelectric
devices wound in a tubular or cylindrical manner and that uses a
magnetic field that is generated from the number of thermoelectric
devices by periodically passing a magnet in the magnetic field to
complete an appropriate thermodynamic cycle such as a Carnot cycle
or a Stirling cycle.
[0012] It is still another object of the present invention to
provide a system for refrigeration with the system using a magnetic
field for cooling with the magnetic field being generated from a
number of thermoelectric devices. The system periodically passes a
magnetic material in the magnetic field and uses a change in the
magnetic entropy of the magnet when the magnetic field is applied
to or removed from the magnetic material.
[0013] It is still yet another object of the present invention to
provide a system for refrigeration that does not use any ozone
destroying refrigerants.
[0014] It is a further object of the present invention to provide a
system that uses a number of thermoelectric elements that are wound
in a cylindrical manner and a second magnetic refrigeration system.
The second system uses a working fluid having fine magnetic
particles therein.
[0015] It is a further object of the present invention to provide a
system that uses a number of thermoelectric elements and a
generator that recaptures energy and converts it to electricity
from the magnetic field applied to a magnetic cooling system. These
and other objects and advantages of the present invention are
achieved by a system for refrigeration of the present invention.
The refrigeration system has a compartment, and a first cooling
device with the first cooling device cooling the compartment and
generating a magnetic field. The refrigeration system also has a
second magnetic refrigerator. The second magnetic refrigerator has
a magnetic material and the magnetic material is periodically
introduced in the generated magnetic field for additional cooling
or an external magnetic field that is applied to a magnetic
material.
DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 shows a thermoelectric device.
[0017] FIG. 2 is a perspective view of a number of thermoelectric
devices being wound in a cylindrical manner around a conduit.
[0018] FIG. 3 is a front view of the conduit of FIG. 2.
[0019] FIG. 4 is a perspective view of a first embodiment of the
refrigeration system of the present invention.
[0020] FIG. 4a shows another embodiment of the refrigeration system
of FIG. 4.
[0021] FIG. 4b shows another embodiment of the refrigeration system
of FIG. 4.
[0022] FIG. 4c shows another embodiment of the refrigeration system
of FIG. 4 in a first position.
[0023] FIG. 4d shows the embodiment of the refrigeration system of
FIG. 4c in a second position opposite the first position.
[0024] FIG. 5 is a perspective view of an another embodiment of the
refrigeration system of the present invention.
[0025] FIG. 6 is a diagram of still another embodiment of the
refrigeration system of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] Referring to FIG. 1, there is shown a cross sectional view
of a thermoelectric element shown as reference numeral 10. The
thermo-electric element or device 10 is preferably a solid state
device. The device 10 has a first P type semiconductor 12 and a
second N type semiconductor 14 with an electron as a charge
carrier. Current from a power supply is passed through the N type
semiconductor 14 to the P type semiconductor 12.
[0027] When current passes therethrough as indicated by reference
arrow 16, heat is removed from surface 20 and transferred through
the thermoelectric device 10, and then deposited to a second
surface 18 of the thermoelectric device as indicated by arrow 22.
The heat removal from the surface 20 causes the absorption of heat
from the adjacent environment through a working fluid in contact
with the cold surface 20. Likewise, the heat generated at surface
18 is ejected through a heat transfer medium. This thermoelectric
device 10 is well known and is understood by those in the art and
requires no further explanation. One skilled in the art will also
appreciate that the thermoelectric device 10 may have another or a
different configuration and the present invention is not strictly
limited to the embodiment shown in FIG. 1. For example, the
thermo-electric device 10 may be tubular shaped.
[0028] Referring now to FIG. 2, a number of thermoelectric devices
10 may be placed in a series 24 as shown and substantially or
completely surround a cylindrical conduit 26. Referring to FIG. 3,
there is shown a view of the cylindrical conduit 26 having the
series 24 of thermoelectric devices 10 substantially surrounding
the conduit 26.
[0029] One skilled in the art will appreciate that once the number
of thermo-electric devices 10 surround the conduit 26, a working
fluid 28 such as ethylene glycol may be pumped or otherwise caused
to traverse through the conduit. The working fluid 28 will be
cooled as it is passed through the interior of the conduit.
Similarly, another working fluid flowing through the exterior
surface of the conduit either in co-flow or counter-flow pattern
with respect to that first working fluid 28 flowing through an
interior of the conduit 26 will be heated. This second working
fluid will carry the heat out of the device for further
ejection.
[0030] Although shown as being used with ethylene glycol, the
working fluid 28 may be any working fluid known in the art or known
in the future and the present invention is not limited to any
specific working fluid. The number of thermoelectric devices 10
surrounding the conduit 26 will then transfer heat from the working
fluid 28 or alternatively transfer heat to the working fluid
depending upon the desired application. Then the working fluid 28
can circulate away from the number of thermoelectric devices 10 to
traverse into a refrigeration compartment, cabin, or any other
desired location to provide a desired cooling and/or heating. As is
understood (and is well known in the art) the working fluid 28 will
transfer heat from the compartment to another external compartment
location and deposit the heat at that location.
[0031] One aspect of placement of the thermoelectric devices 10 in
the cylindrical configuration as shown in FIG. 3 is that the
cylindrical configuration has a number of benefits. These benefits
include enhanced heat transfer, high efficiency, compact
configuration, and ease of manufacture. One significant aspect of
the use of such thermoelectric devices 10 in the cylindrical
configuration is that a magnetic field is generated. Great care in
the prior art has been taken to provide a thick member or a
shielding to prevent this magnetic field from contacting components
and/or individuals.
[0032] The prior art also has taught that the magnetic field should
be contained or handled and is generally a detriment to the
operation of a system. However, the inventors of the present
invention have observed that this energy or magnetic field is
wasted. The inventors instead of simply shielding and wasting this
energy, have instead used this energy to increase refrigeration
capacity and increase productivity of an existing system in a very
unexpected manner and have yielded unexpected benefits from this
wasted energy.
[0033] Referring now to FIG. 4, there is shown a perspective view
of the system 30 of the present invention. It has been observed and
reported that the application of a magnetic field to magnetic
material near a Curie temperature of the specific magnetic material
heats the magnetic material. Conversely, it has been observed that
this same magnetic material will cool upon removal of the magnetic
field. This phenomenon is known in the art as the Magneto-Caloric
effect that requires no further explanation because it is
considered to be well known in the art. Referring now to again FIG.
4, the system 30 preferably has a concentrator 32. The concentrator
32 may be any device or apparatus that preferably concentrates,
modulates or amplifies the existing magnetic field generated by the
number of thermo-electric devices 10 in the preferred cylindrical
configuration.
[0034] The concentrator 32 in one embodiment is a resilient first
core 34 and a second resilient core 36 made from a preselected
material. As is shown, both the first core 34 and the second core
36 are substantially "C" shaped members but are not limited to this
configuration. The first core 34 preferably traverses through an
interior space of the conduit 26. The conduit 26 has a number of
thermo-electric devices 10 or a first thermo-electric device
assembly 38. The second core 36 preferably traverses through a
second thermoelectric device assembly 40 having, again, the number
of thermoelectric devices 10. The cores 34, 36 are made of
materials with high permeability to guide the magnetic field.
[0035] The possible materials for the core 34, 36 may be but not
limited to a ferrite U 60, a ferrite M33, a nickel, a ferrite N41,
iron, a ferrite T38, a silicon steel, and a super alloy or a
super-conducting magnetic material, or other suitable materials.
The cores 34, 36 can have one or multiple individual plates or one
or more rods that are bundled together. One skilled in the art will
appreciate that the number of thermo-electric devices 10 are wound
around a cylindrical surface or conduit 26 as shown in both the
first thermoelectric device assembly 38 and the second
thermo-electric device assembly 40.
[0036] Preferably, in this embodiment each of the cores 34, 36 are
made from materials with high permeability and concentrate the
magnetic field being emitted from the first thermoelectric device
assembly 38 and the second thermoelectric device assembly 40 so the
magnetic field has a first intense region and a second low or zero
region. Since the field generated is proportional to the
permeability of the materials, the cores 34 and 36 are preferably
made with a suitable permeability.
[0037] Preferably, the magnetic field 42 has a first high intensity
shown as reference numeral 44 and a second low or zero intensity
shown as reference numeral 46. The first intensity 44 is greater
than the second intensity 46 and is maximized using available
materials. The system 30 further has a rotatable member 48 having a
rim 50 and a channel 52 in the rim.
[0038] Referring now to an embodiment of the rotatable magnetic
cooling member 48 shown as FIG. 4a, preferably, a channel 33 has
working fluid therein. The rim 50 is made from preferably
gadolinium, a pure material, an alloy and any other combinations
thereof depending on the design requirements such as operating
temperature and temperature range. Some known and possible
materials are gadolinium or a compound thereof such as Gd.sub.5
(Si.sub.xGe.sub.1-x).sub.4 (with a magneto-caloric effect), alloys
of Gd and Dy, and any other suitable alloy known in the art. The
rim 50 is preferably made from any paramagnetic material,
ferromagnetic material, or more preferably the material with a
suitable magneto-caloric effect (MCE). Preferably, the rotatable
member 48 rotates so the working fluid in the rim 50 traverse
periodically from the first intensity 44 to the second intensity
46. In this manner, the rim 50 of the rotatable member 48 heats
when the rim is in the first intensity 44 and then cools when the
rim is away from the first intensity or in the second intensity 46.
Thus, the working fluid in a channel 33 is cooled and is placed in
spaced relation to another second working fluid or device that can
transfer heat thereto and then communicates with a compartment for
cooling (not shown).
[0039] Referring to FIG. 4a, the system 30 may have a rotating
member 48 with the rim 50 having a number of channels 33 therein.
The channels 33 are generally cylindrically shaped and are located
around the rim 50 of the rotating member 48. Alternatively, the
channels 33 may have another shape other than generally cylindrical
such as oblong or rectangular shaped or may be one discrete
channel. Each of the channels 33 preferably has the working fluid
therein. The rotating member 48 preferably rotates the channels 33
having the working fluid therein in a cycle 51 as shown. The cycle
51 preferably to ejects heat shown as letter Qh with a first heat
exchanger at a first location 35. The cycle 51 also has a pumping
mechanism and another second heat exchanger 37 for cooling as
letter Qc to provide cooling. The rotating member 48 rotates at a
rate sufficient to transfer heat and to provide cooling from the
magneto-caloric effect when rotating. Thus, the magnetic field 44
provides an additional amount of cooling to the compartment. It has
been observed that an additional cooling system with a high Carnot
efficiency of about sixty percent can be realized by the magnetic
refrigeration cycle using a moderately strong magnetic field.
[0040] Referring now to still another embodiment of the present
disclosure shown in FIG. 4b, the rotating member 50 may spaced
between two loops, or a first loop 61 and a second loop 63 to more
adequately transfer heat. Each of the loops has a pump 65.
Preferably, the first loop 61 may be disposed on a first side of
the rotating member 50 and have a first heat exchanger 67 for heat
ejection. In this manner, the working fluid in the channel 33 in
the rotating member 50 preferably transfers or ejects heat into the
first loop 61, that is in turn ejected to ambient. Thereafter, upon
rotation a predetermined radial amount the working fluid in the
channel 33 provides cooling to the second loop 63. The second loop
63 is spaced from the rotating member 50. The second loop 63 will
then thermally communicate to a second heat exchanger 69 and
transfer heat from the desired compartment.
[0041] In another preferred embodiment of the present invention,
system 30 has a ferromagnetic or paramagnetic material in a first
member that is axially or laterally moved to and from the magnetic
field 44 to provide cooling. The first member 71 preferably has a
cylindrical piston configuration and reciprocates from a first
location 73 to a second location 75. The first member 71 may also
have the channel 52 with a working fluid therein as discussed
above. Referring now to FIG. 4c, there is shown another exemplary
embodiment of the system 30. Preferably, the first location 71 is a
complementary location to a relatively high magnetic field and thus
ejects heat to a first loop 77 that is communicating with a heat
exchanger 79. The second location 75 or down stroke of the first
member 71 is communicating with a second loop 81 with a second heat
exchanger 83. This second loop 81 provides cooling to for example a
compartment. Referring now to FIG. 4d, as shown the first member 71
moves from the first position 73 to the second position 75, the
first member will removes heat from the second location 75 where
the magnetic field is weaker relative to the first position. Once
removed from the strong magnetic field (as shown in FIG. 4c) the
first member 71 draws heat therein from the second loop 81 for the
cooling phase. The first member 71 preferably reciprocates a number
of different times in order to provide additional cooling to the
compartment or other desired location.
[0042] Alternatively, referring to another embodiment of the
present invention shown in FIG. 5. The system 30 may alternatively
recapture the energy from the magnetic field in the form of
electricity to be stored in a battery or to power the number of
thermo-electric devices 10. In this embodiment, the system 30 has a
magnetic cooling system 59 with a first heat ejection loop 56 and a
second cooling loop 58. An alternating magnetic field is applied to
a magnetic cooling component 59 and generates cooling. The system
30 also has a generator 54 that recovers and converts part of the
magnetic energy from 90 to electricity. The generator 54 preferably
generates and conditions electricity for powering a thermoelectric
assembly 57. The system 30 preferably has a thermoelectric assembly
57 with a first heating loop 95 and a second cooling loop 98. The
number of thermoelectric devices 10 in the assembly 57 have the
thermo-electric devices 10 in a planar or cylindrical
configuration. In this embodiment, the otherwise wasted energy from
the magnetic field is recaptured. One skilled in the art should
appreciate that the electric current produced may be directly
connected to the number of thermoelectric devices 10 or
alternatively may be stored for later usage. One significant aspect
of the present invention is that the energy is recaptured during
heating or cooling for an increased productivity.
[0043] Referring now to FIG. 6, there is shown another preferred
embodiment of the present invention. In this preferred embodiment,
the system 30 has the conduit 26 with the number of thermo-electric
devices 10 wound around the conduit. The system 30 also has a
second conduit 60. The second conduit 60 is formed in a loop
configuration. The conduit 26 preferably has any number of
thermoelectric devices 10 being wound in a cylindrical
configuration. This configuration provides the requisite cooling
and/or heating desired and has the second conduit 60 traversing
through an interior space of the conduit 26. The thermoelectric
devices 10 are preferably wound around the second conduit 60
through the conduit 26 at a discrete point. The thermo-electric
devices 10 preferably form a magnetic field 62. The magnetic field
62 is at a discrete point of the loop, and preferably intense at
that discrete point while the loop also has a portion of the loop
located at a less intense other weaker point. One skilled in the
art should appreciate that the thermoelectric devices 10 may be
placed at any number of discrete points along the loop so long as
the number of thermo-electric devices are wound in the tubular or
substantially cylindrical fashion.
[0044] Preferably, the second conduit 60 has a working fluid 28
therein that is preferably ethylene glycol or alternatively any
other working fluid known in the art. The working fluid 28 in the
second conduit 60 further preferably has a number of fine magnetic
particles 64 disposed therein in a suspension. One skilled in the
art will appreciate that the fine magnetic particles 64 have a size
that does not prevent or impair any fluid flow properties of the
working fluid 28 in the second conduit 60.
[0045] Once the working fluid 28 having the number of fine magnetic
particles 64 disposed therein traverses into the magnetic field 62
and is magnetized, the fine suspended magnetic particles 64 will be
heated. Once the working fluid 28 having the number of fine
magnetic particles 64 disposed therein traverses through the
magnetic field 62 the heat generated will be deposited to a heat
sink through a heat exchanger 85, thus the temperature of the
magnetic particles containing working fluid initially increases and
then decreases after it is passed through the heat exchanger. After
existing the heat exchanger 85, the magnetic particles will then
cool at another second location 66 with low or zero magnetic field.
The system 30 further has another heat exchanger 68 that will then
transfer heat from the third loop to the working fluid 28 in the
second conduit 60. The third loop 68 will then traverse into the
desired compartment for additional cooling and for use as an
auxiliary or second cooling system. The magnetic particles are
preferably made from the materials with large magneto-caloric
effect as those previously indicated.
[0046] It should be understood that the foregoing description is
only illustrative of the present invention. Various alternatives
and modifications can be devised by those skilled in the art
without departing from the invention. Accordingly, the present
invention is intended to embrace all such alternatives,
modifications and variances.
* * * * *