Note: Descriptions are shown in the official language in which they were submitted.
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ICE-MAKING APPARATUS
FIELD OF THE INVENTION
[0001] The present disclosure relates to an ice generator capable of making
ice slurry by
absorbing heat energy when a refrigerant is evaporated. To be specific, the
present
disclosure relates to an ice slurry generator with increased efficiency and
productivity by
modifying the structure for heat exchange between a refrigerant and a carrier
fluid.
BACKGROUND OF THE INVENTION
[0002] Generally, ice slurry has excellent heat storage, fluidity, ability as
a refrigerant, and
heat release compared to a conventional refrigerant. Therefore, the ice slurry
is expected to
take on a greater role in heat storage and cold heat transportation and to be
recognized as a
core technology for a next-generation heating and cooling system. However, the
market
demand for ice slurry-based cooling systems has been stagnant for many years.
Many
scholars and researchers have claimed that the reason for such stagnation is
the lack of an
economical and reliable ice generator that is scalable and easily
maintainable. Accordingly,
the first priority in the expansion of the role of the ice slurry is to obtain
an economical and
reliable ice slurry generator.
[0003] Such an ice generator can be attained through a different version of
the common
shell and tube heat exchanger-type ice generator. The efficacy of the shell
and tube model
has been partially proven with the vertical shell and tube heat exchanger.
However, the
maximum capacity of all vertical shell and tube type products developed so far
has not been
scaled up above approximately 500 kW/unit (based on ice generation capacity).
Furthermore, in all models so far, ice particles cannot be present at the
outset of the ice
generator cycle, as this results in inoperability due to clogging. Thus, it is
difficult to apply
the ice generator to a direct transportation system. For domestic products, as
the size of an
ice generator is increased, the power consumption of the circulation pump is
disproportionately increased during ice slurry production.
[0004] In accordance with a whip rod heat exchanger described in U.S. Patent
No.
5,768,894, a carrier fluid is uniformly introduced into the top of the
vertical heat exchanger
tubes. Then, a whip rod inside each heat transfer tube is rotated at high
speed with an
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orbital motion. The orbital motion generates a centrifugal force that causes
the whip rod to
rotate in contact with the inner surface of the heat transfer tube. Thus, the
ice layer is
scraped from the inner surface and flows down to be collected at a lower area
of the heat
transfer tube due to gravity. A slurry pump sucks the collected ice slurry and
discharges the
ice slurry to the bottom discharge chamber. However, the flow velocity of the
carrier fluid
at the inlet chamber is greatly decreased in order to uniformly distribute the
carrier fluid.
Therefore, if even a small amount of ice particles is externally introduced
into the apparatus,
the ice particles continue to pile up at an upper area of the inlet chamber
and the inlet
chamber becomes clogged. Even if an additive to increase fluidity is used,
this problem
cannot be avoided. If the ice generator is connected to a heat storage tank in
order to apply
it to a direct transportation system, a high concentration of ice particles is
unavoidably
introduced into the inlet chamber. Thus, the inlet chamber is often clogged
and operation
becomes very difficult. For this reason, this apparatus cannot be applied to
the direct
transportation system and thus has been used for a cooling-only ice storage
system that uses
an ice-bed type heat storage tank. The discharge section of the ice slurry
generator is
frequently clogged as well. Furthermore, it is difficult to manufacture this
apparatus on a
large scale as the drive plate, which is a main component for power transfer,
cannot be
scaled up due to the limitation of its mechanical strength. Therefore, this
apparatus is not
suitable for a large scale heat source system such as a district cooling
system. Furthermore,
abrasion of the driving components is quite common, and the cost of
maintenance is greatly
increased as a result. Korean Patent No. 10-0513219 describes efficiency in
discharging ice
slurry to the outside of an ice generator as a requisite feature of an ice
generator. To be
specific, in an ice generator, guide plates slanted toward the outlet are
provided in a
counter-flow discharge chamber. However, despite the presence of the guide
plates,
additional pumping head ranging from about 0.2 bar to about 0.8 bar (depending
on a size
of the ice generator) is needed in order to discharge the ice slurry from the
ice generator.
The necessary additional pumping head is proportional to the capacity of the
ice generator.
Compared to the basic pumping head for uniform distribution, power consumption
is
greatly increased by the additional pumping head. If ice slurry containing a
high
concentration of ice particles is introduced into the ice generator, the ice
particles and the
water separate at the inlet, and the ice generator may become partially
clogged. Therefore,
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ice generator components with better discharge and clogging prevention
capabilities are
necessary.
[0005] Meanwhile, ice generators of the single tube scraper-type, the disc-
type, the
vacuum-type, and the fluidized bed-type have been developed in Europe and
North
America. However, these apparatuses are not priced competitively, are not
suitable for a
thermal storage system due to their small capacity, and are used only for a
specific purpose
due to high cost. Although the single tube scraper-type apparatus of a small
capacity has
high reliability and excellent circulation capability, it is limited in usage
to cooling marine
products, due to limited capacity and lack of competitive prices. In addition,
it is very
difficult to return the ice slurry from vacuum to atmospheric pressure;
because of this, the
vacuum-type apparatus cannot be commercialized.
[0006] In a fluidized bed-type apparatus, it is difficult to separate the ice
particles from the
metal or plastic balls that are used in a fluidized bed. Accordingly, the
height of the
apparatus must be greatly increased, resulting in difficulty in transporting
the separated ice
particles. Another type of apparatus has been developed that makes the ice
slurry on a
smooth, lab-scale evaporation plate in order to prevent ice particles from
becoming stuck to
the plate. However, a long term operation is not viable due to issues of
surface
contamination. Moreover, actual competitiveness is still questionable due to
the
complicated conditions required for operation.
[0007] The multilayer disc and brush-type ice generating method recently
developed in
Canada allows for a capacity of about 500 kW/unit. However, there is not yet a
way to
efficiently collect the generated ice slurry from this method.
[0008] A super-cooled water-type ice generating method has been developed
primarily in
Japan. The great technical advances in this method have been commercialized
widely in an
ice storage system. However, for direct transportation applications, the
efficacy of the
system is limited by clogging (caused by phase separation) and agglomeration
(caused by
re-crystallization and the bridging phenomenon). Furthermore, in order to
continuously
generate super-cooled water, the ice generator needs a highly efficient filter
for removing
fine impurities/particulates from the water, a preheating device to prevent
the unwanted
introduction of ice particles, and an indirect cooling evaporator (it is
impossible to directly
exchange heat with a refrigerant). Therefore, the operation becomes
overcomplicated.
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Accordingly, despite its technical superiority, usage of the super-cooled
water-type ice
generator is not expanding.
[0009] Recently, there has been one more trial to develop an improved scraper-
type ice
generating method. An attempt was been made in the U.S., in which the outer
surface of the
whip rod was coated with a plastic to prevent abrasion of the whip rod.
However, the heat
transfer tube had a problematic driving system, issues in circulation due to a
larger whip
rod that blocked the ice particles from flowing downward, and stagnation of
the ice slurry
in the inlet of the distribution chamber.
[0010] In conclusion, ice generators have high potential for effective use in
heat pump
systems, but in order for them to be widely used, they need to be economically
feasible,
scalable and free of clogging problems incurred during circulation.
BRIEF SUMMARY OF THE INVENTION
[0011] In accordance with an illustrative embodiment of the present
disclosure, there is
provided a scalable ice generator with improved efficiency and productivity
due to
modifications in the structure of the heat exchange between a refrigerant and
a carrier fluid.
[0012] In accordance with an illustrative embodiment of the present
disclosure, there is
provided an ice generator that prevents an overload of components by
minimizing logging
and agglomeration of the ice slurry within the apparatus and enables efficient
circulation of
the ice slurry.
[0013] In accordance with an embodiment of the present disclosure, there is
provided an ice
generator that includes: a heat exchanger configured to absorb heat energy
while a
refrigerant is evaporated; multiple horizontal heat exchange passages provided
within the
heat exchanger and configured for heat exchange between a carrier fluid and
the refrigerant;
inlet and discharge chambers that are connected to the heat exchange passages;
screw-like
scrapers within the heat exchange passages that transport the carrier fluid
from the inlet
chamber to the discharge chamber via rotation; and a driving unit that rotates
the scrapers.
[0014] In accordance with one aspect of the present disclosure, at least one
scraper should
be extended from the heat exchange passages into either the inlet chamber or
the discharge
chamber.
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[0015] In accordance with one aspect of the present disclosure, the ice
generator also
includes stirring units with radial paddles that are installed in both the
discharge and inlet
chambers. They prevent clogging caused by phase separation of the carrier
fluid during
rotation.
[0016] In accordance with one aspect of the present disclosure, the gap
between the edge of
the scraper blade and the inner surfaces of the heat exchange passages should
be between
0.1 mm to 0.4 mm.
[0017] In accordance with one aspect of the present disclosure, one face of a
scraper blade
is flat, while the other face is convex.
[0018] In accordance with one aspect of the present disclosure, the ice
generator includes
supporting members for the heat exchange passages, and the supporting members
are made
of plastic.
[0019] In accordance with one aspect of the present disclosure, the discharge
chamber
includes a discharge opening to expel the carrier fluid to the outside; flat
guide plates
inclined within the heat exchange passages guide the carrier fluid toward the
discharge
opening.
[0020] In accordance with one aspect of the present disclosure, a scraper may
penetrate the
guide plates.
[0021] In accordance with one aspect of the present disclosure, the inlet
chamber may
include one or more inlet openings. If there are multiple inlet openings, they
are arranged
symmetrically in a radial direction with respect to the inlet chamber.
[0022] The effect of the Invention can be described as follows. Firstly, the
scrapers are
extended into the inlet chamber or the discharge chamber so as to smoothly
stir the carrier
fluid; such extensions make it possible to prevent clogging or agglomeration
caused by
phase separation of the solid-liquid carrier fluid.
[0023] Secondly, the extension of scrapers into the inlet chamber can prevent
stagnation
caused by a difference in the flow velocity of the carrier fluid and/or a
difference in the
distance from the inlet opening to each heat exchange passage.
[0024] Thirdly, it is possible to efficiently remove any solidified medium
from the inner
surface of the heat exchange passage, despite the relatively slow rotation of
the scrapers, by
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maintaining a gap between the scraper and the inner surface of the heat
exchange passage.
This makes it possible to perform a continuous operation.
[0025] Fourthly, a scraper maintains its precisely fitted position within its
respective heat
exchange passage regardless of whether the ice generator is on or off. This
prevents
abrasion of the inner sides of the heat exchange passage. Because the scraper
does not shift
from its position at the center of the heat exchange passage, the heat
exchange passage can
be positioned at any angle regardless of gravitational direction.
[0026] Fifthly, the ice generator is aligned horizontally, so that the
refrigerant outside of the
heat exchange passages can be maintained in a nucleate boiling condition.
Thus, it is
possible to increase the efficiency of heat transfer. Moreover, a horizontal
driving unit is
more accessible to maintenance workers than vertical types. Further, a
horizontal heat
exchange passage can be made to be longer than a vertical type can be made
tall, so that it
is more feasible to scale the generator up, although the scale is also
dependant on the
strength of the driving unit.
[0027] Sixthly, the stirring units that guide the carrier fluid toward the
discharge opening
aid the overall prevention of clogging or agglomeration.
[0028] Seventhly, because the scraper does not shift from the center of the
inside of the heat
exchange passage during operation, rotational vibration of the scraper can be
minimized.
Even if excessive power is applied to the scraper, as it is when the generator
senses
potential clogging in the heat exchange passage, the heat exchange passage is
supported by
an external member(s) that suppresses rotational vibration. This is possible
because the
external member(s) is/are made of flexible plastic material that absorbs high
frequency
vibration, so that the transfer of the vibration to other components is
minimized.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Fig. 1 is a cross sectional view of an ice generator in accordance with
an illustrative
embodiment;
[0031] Fig. 2 is a cross sectional view taken along a line I-I in Fig. 1;
[0032] Fig. 3 is a partial cross sectional view showing a modified part of the
ice generator
depicted in Fig. 1;
[0033] Fig. 4 is a cross sectional view taken along a line II-II in Fig. 3;
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[0034] Fig. 5 is a cross sectional view of another ice generator in accordance
with another
illustrative embodiment;
[0035] Fig. 6 is a cross sectional taken along a line in Fig. 5;
[0036] Fig. 7 is a measured graph showing variations in power of a scraper
during the
operation of a conventional ice generator;
[0037] and [0038] Fig. 8 is a measured graph showing variations in power of a
scraper
during the operation of an ice generator in accordance with an illustrative
embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0039] Hereinafter, illustrative embodiments of the present disclosure will be
described in
detail with reference to the accompanying drawings. However, it is to be noted
that the
present disclosure is not limited to the illustrative embodiments.
[0040]
[0041] An ice generator in accordance with an illustrative embodiment of the
present
disclosure will be explained with reference to Figs. 1 and 2. Fig. 1 is a
cross sectional view
of an ice generator in accordance with an illustrative embodiment and Fig. 2
is a cross
sectional view taken along a line I-I in Fig. 1.
[0042] As depicted in the drawings, the ice generator includes a heat
exchanger 100, heat
exchange passages 110, an inlet chamber 120, a discharge chamber 130, scrapers
200, and a
driving unit 170.
[0043] The heat exchanger 100 is primarily used to absorb heat energy from the
ice slurry
while the refrigerant is evaporated within the inner space of the heat
exchanger 100.
[0044] The heat exchange passage 110 is aligned horizontally within the heat
exchanger
100, and the carrier fluid interacts with the refrigerant while passing
through the heat
exchange passages 110. There are multiple heat exchange passages 110 shaped
like hollow
pipes. Preferably, the heat exchange passages should be made of a surface
processed copper
tube that is ideal for accelerating nucleate boiling, but other materials
could be used.
[0045] The inlet chamber 120 is connected to the heat exchange passage 110 on
one side of
the heat exchanger 100, so as to introduce the carrier fluid into the heat
exchange passage
110. The discharge chamber 130 is connected to the heat exchange passage 110
and is
provided on the opposite side of the inlet chamber 120 on the heat exchanger
100. The
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carrier fluid exits through to the discharge chamber 130 from the heat
exchange passage
110.
[0046] The inlet chamber 120 includes an inlet opening 125; the carrier fluid
is introduced
into the inlet chamber through the inlet opening 125. The discharge chamber
130 includes a
discharge opening 135 for discharging the carrier fluid, by which heat is
completely
exchanged with the outside via the ice slurry. Details will be described with
reference to Fig.
2 or Fig. 5.
[0047] The scraper 200 in Fig. 2 includes a rod member 210 and a blade 220.
Preferably,
the rod member 210 should be slightly longer than the heat exchange passage
110 so as to
be extended a certain length into the inlet chamber 120 or the discharge
chamber 130, but it
is not limited thereto. In other words, the rod member 210 may have the same
length as the
heat exchange passage 110 or the rod member 210 may be extended into one of
the inlet
chamber 120 or the discharge chamber 130.
[0048] The blade 220 wraps in a screw-like fashion around the outside of the
rod member
210. Relative to the direction of rotation of the scraper 200, the front face
of the blade 220
forms a convex surface and the back face forms a flat surface.
[0049] The scraper 200 is inserted into the heat exchange passage 110. As the
scraper 200 is
rotated, the carrier fluid introduced from the inlet chamber 120 into the heat
exchange
passage 110 is transported toward the discharge chamber 130 inside the heat
exchange
passage 110 by the spiraled blade 220. The carrier fluid is transported while
in contact with
the heat exchange passage 110, so that heat exchange is performed. In other
words, the
scraper 200 both transport the carrier fluid toward the discharge chamber 130
and removes
any solidified medium on the inner surface of the heat exchange passage 110,
thus
increasing the efficiency of heat transfer.
[0050] The driving unit 170 is connected to, but not limited to, a commonly
used motor; a
gear is connected to the motor to provide a rotational driving force to the
scraper 200. Any
motor can be used if it can output the power required to operate the ice
generator and
provide a driving force capable of rotating the scraper 200.
[0051] Since one or more of the scrapers 200 extend into the inlet chamber 120
or the
discharge chamber 130, the scraper 200 can prevent clogging or agglomeration
caused by
phase separation of the carrier fluid.
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[0052] Thus, the scraper 200 enables the carrier fluid to smoothly flow
through the inlet
chamber 120 or the discharge chamber 130.
[0053] In the ice generator configured as described above, when the carrier
fluid is
introduced into the inlet chamber 120 of the ice generator, the flow velocity
of the carrier
fluid is decreased due to an increased cross sectional area.
[0054] Previously, the carrier fluid may have become stagnant because the flow
velocity
was different at each part of the carrier fluid, and/or because the distance
between the inlet
opening 125 and each heat exchange passage 110 was not uniform, but the
scrapers 200
prevent such stagnation because they are extended into the inlet chamber 120.
[0055] The width of the blade 220 should be determined so as to maintain a gap
between
the edge of the blade 220 of the scraper 200 and the inner surface of the heat
exchange
passage 110 within a range of 0.1 mm to 0.40 mm.
[0056] The driving unit 170 is operated so as to rotate the scraper 200 at
speeds between
200 rpm and 450 rpm.
[0057] The sharp edge of the blade 220 can further reduce any potential dry-
out points on
the inner surface of the heat exchange passage 110 during rotation.
Preferably, the edges of
the blades 220 of the scrapers 200 for each respective heat exchange passage
110 should
have a thickness of, but not limited to, approximately 0.1 mm.
[0058] When the ice generator is operating, the carrier fluid forms a thin
liquid film that is
continuously formed and destroyed by the contact between the edge of the blade
220 and
the inner walls of the heat exchange passages. This film acts as a lubricant
for the blades,
and speeds up the entire heat transfer process.
[0059] The convex shape of the front face of the blade 220 ("front" with
respect to the
direction of the movement of the carrier fluid during operation) compresses
the carrier fluid
while the flat back face, in comparison with the convex front face,
decompresses the carrier
fluid. This creates a partial vortex, which relieves supercooling and
accelerates the phase
separation of the carrier fluid. Thus, the level of supercooling of the
carrier fluid can be
controlled in order to generate soft ice slurry.
[0060] The ice generator may become overloaded if the gap between a blade 220
and the
respective heat exchange passage 110 is increased. This is because the widened
gap causes
the level of supercooling to increase as well; as a result hardened ice may
form on the inner
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surface of heat exchange passages, and the scraper 200 may be unable (due to
the overload
of the carrier fluid) to remove the hardened ice. Thus it is necessary that
the gap remains at
the same width at all times in order to ensure uninterrupted operation.
[0061] Furthermore, in order to prevent agglomeration or clogging within
discharge
chamber caused by interaction between discharged carrier fluid from adjacent
heat
exchange passages 110, the scraper 200 in a given heat exchange passage 110
should be
rotated in the opposite direction to a scraper 200 in an adjacent heat
exchange passage 110.
[0062] For configuration described above, the power consumption for the ice
generator, in
accordance with the illustrative embodiment, is minimized because the
overloading typical
of a conventional ice generator does not occur and thus efficiency of heat
transfer is
increased. This result is shown in Figs. 7 and 8. Fig. 7 is a measured graph
showing
variations in power consumption of a conventional ice generator and Fig. 8 is
a measured
graph showing variations in power consumption of an ice generator that is in
accordance
with the illustrative embodiment.
[0063] By looking at the variations in power consumption, it can be deduced
that initial
overloading of the ice generator that is in accordance with the illustrative
embodiment is
relatively low compared to the conventional ice generator.
[0064] When the blade 220 is maintained in the correct shape and position, any
deviation
between the stop position of the scraper 200 and an operation position can be
reduced. And
because any deviation is minimized, the heat exchange passages 110 and thus
the entire ice
generator can be positioned horizontally so as to be perpendicular with the
direction of
gravity.
[0065] Therefore, the ice generator in accordance with the illustrative
embodiment of the
present disclosure can be aligned to be horizontal. In other words, the
carrier fluid is
transported from the inlet chamber 120 to the discharge chamber 130 as the
scraper 200 is
rotated, and, thus, the heat exchange passage 110 is aligned to be in parallel
with the
direction of the surface of the earth. The discharge chamber 130, the inlet
chamber 120, and
the driving unit 170 are provided at a side surface of the heat exchanger 100,
so that a large
quantity of the carrier fluid can flow through and the influence of gravity
can be minimized.
[0066] Since the ice generator is aligned horizontally, the refrigerant
outside the heat
exchange passage 110 can be maintained in a nucleate boiling condition. This
can increase
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the efficiency of heat transfer. Furthermore, since the driving unit 170 is
also positioned
horizontally, it is easily accessible for maintenance work, compared to a case
where the
driving unit 170 is positioned vertically. Furthermore, the horizontal heat
exchange passage
110 can be made longer than the vertical type can be made taller, so that the
ice generator is
more scalable.
[0067]
[0068] Although it has been described that the scrapers 200 of the ice
generator in
accordance with the illustrative embodiment are extended to either the
discharge chamber
130 or the inlet chamber 120 so as to stir the carrier fluid, the present
disclosure is not
limited thereto. For more detailed explanation thereof, Figs. 3 and 4 are
provided.
[0069] Fig. 3 is a partial cross sectional view showing a modified version of
the part of the
ice generator depicted in Fig. 1, and Fig. 4 is a cross sectional view taken
along a line II-II
in Fig. 3. For the sake of convenient explanation, explanations of similar or
same
components as illustrated in Figs. 1 and 2 will be omitted.
[0070] As depicted in the drawings, the ice generator further includes a
stirring unit 400.
[0071] The stirring unit 400 is provided in the discharge chamber 130 and
includes radial
paddles. The stirring unit 400 is formed in a shape substantially similar to,
but not limited
to, a propeller.
[0072] The stirring unit 400 stirs the carrier fluid discharged from the heat
exchange
passage 110 so as to suppress clogging caused by the phase separation of the
carrier fluid.
[0073] The carrier fluid discharged from the heat exchange passage 110 is
prone to causes
agglomeration or clogging within the heat exchange passage 110 in the form of
ice slurry,
but the stirring unit 400 works to circulate and guide the carrier fluid
toward the discharge
opening 135. Thus, it is possible to suppress clogging or agglomeration.
[0074]
[0075] The ice generator in accordance with a second illustrative embodiment
of the
present disclosure will be explained with reference to Figs. 5 and 6 as
follows. Fig. 5 is
another cross sectional view of ice generator in accordance with the second
illustrative
embodiment and Fig. 6 is a cross sectional view taken along a line in Fig.
5.
[0076] As depicted in the drawings, the ice generator includes the heat
exchanger 100, the
heat exchange passage 110, the inlet chamber 120, the discharge chamber 130,
the scraper
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200, the driving unit 170, a supporting member 115, and a guide plate 300. For
the sake of
convenient explanation, explanations of similar or same components as
illustrated with
reference to Figs. 1 to 4 will be omitted.
[0077] The flat guide plate 300 is provided in the discharge chamber 130. The
guide plate
300 is inclined toward a certain direction at a predetermined angle with
respect to the heat
exchange passage 110 so as to best guide the carrier fluid toward the
discharge opening 135.
[0078] The parts of the scrapers 200 that extend to the discharge chamber 130
penetrate the
guide plate 300. The guide plate 300 configured as described above separates
the carrier
fluid remaining outside the scraper 200, i.e. the carrier fluid transformed
into ice slurry and
congealing on the surface of the scraper 200, from the scraper 200 and guides
the separated
carrier fluid toward the discharge opening 135.
[0079] The carrier fluid becomes increasingly laden with ice particles as it
passes through
the heat exchange passage 110 toward the discharge chamber 130. Because of the
increasing level of ice particles, the circulation of the carrier fluid is
relatively slow. Yet the
carrier fluid still flows smoothly because of the flow path provided by the
guide plate 300
and the extension of the scraper 200 into either the discharge chamber 130 or
the inlet
chamber 120.
[0080] If the capacity of the ice generator is increased, the number of the
heat exchange
passages 110 may be increased to about 200 or more. The heat exchange passages
110 may
be divided into several groups and a passage space may be formed between the
groups to
allow for the smooth flow of the carrier fluid.
[0081] The discharge opening 135 is in the upper portion of the discharge
chamber 130, so
that the carrier fluid can be easily discharged through the discharge opening
135 by means
of buoyancy.
[0082] Multiple inlet openings 125 may be formed in the inlet chamber 120.
Similarly,
multiple discharge openings 135 can be formed.
[0083] In this case, the inlet openings 125 are arranged symmetrically in a
radial direction
in the inlet chamber 120 in order to better control the flow of the carrier
fluid when
introduced into the inlet chamber 120. Accordingly, by optimizing the
arrangement of the
inlet openings 125, it is possible to minimize variations in flow velocity
caused by the
varied positions of the heat exchange passages 110 within the inlet chamber
120.
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[0084] The carrier fluid is directly introduced into the inlet chamber 120
without passing
through a separate distribution device, and becomes homogeneous as a result of
the stirring
action of the scraper 200 within the inlet chamber 120.
[0085] A bypass tube 119, separate from the heat exchange passages 110, may be
further
provided to connect the discharge chamber 130 to the inlet chamber 120.
[0086] The bypass tube 119 is used to move the carrier fluid in the inlet
chamber 120 to the
discharge chamber 130 when the amount of the carrier fluid introduced into the
inlet
chamber 120 is increased too quickly or if the carrier fluid does not flow
smoothly in some
of the heat exchange passages 110. If necessary, the bypass tube 119 may
include a valve
(not illustrated) for opening.
[0087] The supporting member 115 supports the heat exchange passages 110.
Multiple
members 115 may be arranged at intervals of 500-900 mm depending on a length
of the
heat exchange passages 110 so as to prevent the heat exchange passage 110 from
drooping,
as well as to suppress vibration of the heat exchange passages 110 during
operation of the
ice generator.
[0088] Preferably, the supporting members 115 are positioned in contact with
the heat
exchange passages 110 in order to prevent damage or decoupling of vibration
between the
heat exchange passage and other components. The supporting member 115 is made
of
plastic in order to protect the heat exchange passage 110.
[0089] In the ice generator that is in accordance with the illustrative
embodiment, there is a
small gap between the edge of the blade 220 of the scraper 200 and the inner
surface of the
heat exchange passage 110. Moreover, the blade 220 has the curved front
surface described
previously. Thus, when the scraper 200 is rotated, the scraper 200 pushes the
carrier fluid
out toward the inner surface of the heat exchange passage 110. This prevents
the scraper
from shifting from the center of the heat exchange passage during operation.
As a result, the
rotational vibration of the scraper is minimized.
[0090] Even if excessive power is applied to the scraper 200 due to the ice
generator's
detection of potential clogging within a heat exchange passage 110, the heat
exchange
passage 110 is supported by an external member that suppresses rotational
vibration caused
by the scraper 200. The external member is made of a flexible plastic material
that absorbs
high frequency vibration.
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14
[0091]
[0092] Although the present disclosure has been explained with reference to
the illustrative
embodiments described above and the accompanying drawings, the present
disclosure is
not limited thereto and can be modified and changed in various ways by those
with
sufficient expertise in this field.
[0093] Therefore, the scope of the present disclosure is defined by the
following claims and
their equivalents rather than by the detailed description of the illustrative
embodiments.
