U.S. patent application number 12/796014 was filed with the patent office on 2011-04-28 for dual turbo centrifugal chiller.
Invention is credited to Tae Jin Kang, Jin Sung Kim, Kil Young Kim.
Application Number | 20110094251 12/796014 |
Document ID | / |
Family ID | 43897216 |
Filed Date | 2011-04-28 |
United States Patent
Application |
20110094251 |
Kind Code |
A1 |
Kim; Kil Young ; et
al. |
April 28, 2011 |
DUAL TURBO CENTRIFUGAL CHILLER
Abstract
A dual turbo centrifugal chiller includes: first and second
evaporators connected in series or in parallel; first and second
condensers connected in series or in parallel; and first and second
compressors including impellers, wherein cold water passes through
the second evaporator after passing through the first evaporator,
and cooling water passes through the second condenser after passing
through the first condenser, the first compressor containing a
refrigerant connects the first condenser to the second evaporator,
and the second compressor containing a refrigerant connects the
second condenser to the first evaporator, and the impellers of the
first compressor and second compressor are rotated simultaneously
using a single driving unit.
Inventors: |
Kim; Kil Young; (Gwanak-gu,
KR) ; Kim; Jin Sung; (Suseong-gu, KR) ; Kang;
Tae Jin; (Gunpo-si, KR) |
Family ID: |
43897216 |
Appl. No.: |
12/796014 |
Filed: |
June 8, 2010 |
Current U.S.
Class: |
62/335 ;
62/510 |
Current CPC
Class: |
F25B 2339/047 20130101;
F25B 2400/0751 20130101; F25B 1/10 20130101; F25B 1/053
20130101 |
Class at
Publication: |
62/335 ;
62/510 |
International
Class: |
F25B 7/00 20060101
F25B007/00; F25B 1/10 20060101 F25B001/10 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 27, 2009 |
KR |
10-2009-0102209 |
Claims
1. A dual turbo centrifugal chiller, comprising: first and second
evaporators connected in series or in parallel; first and second
condensers connected in series or in parallel; and first and second
compressors including impellers, wherein cold water passes through
the second evaporator after passing through the first evaporator,
and cooling water passes through the second condenser after passing
through the first condenser, the first compressor containing a
refrigerant connects the first condenser to the second evaporator,
and the second compressor containing a refrigerant connects the
second condenser to the first evaporator, and the impellers of the
first compressor and second compressor are rotated simultaneously
using a single driving unit.
2. The dual turbo centrifugal chiller according to claim 1, wherein
the impellers of the first and second compressors are connected
with a single rotation shaft, and the impellers of the first and
second compressor are rotated simultaneously as the rotation shaft
is rotated using the driving unit.
3. The dual turbo centrifugal chiller according to claim 2, wherein
the driving unit is connected to the center of the rotation shaft,
and the impellers of the first and second compressors are opposed
with the center of the rotation shaft between them.
4. The dual turbo centrifugal chiller according to claim 1, wherein
inlet portions of the first and second compressors are provided
with inlet guide vanes (IGVs) respectively.
5. The dual turbo centrifugal chiller according to claim 3, wherein
the first and second compressors have different capacities from
each other.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to Korean Patent
Application No. 10-2009-0102209, filed on Oct. 27, 2009, and all
the benefits accruing therefrom under 35 U.S.C. .sctn.119, the
contents of which in its entirety are herein incorporated by
reference.
BACKGROUND
[0002] 1. Field
[0003] This disclosure relates to a dual turbo centrifugal chiller,
particularly to a dual turbo centrifugal chiller configured to
decrease head of a compressor among components of two individual
chillers, decrease the size of the chiller, and increase
efficiency.
[0004] 2. Description of the Related Art
[0005] A general chiller includes a compressor, an evaporator, a
condenser, and an expansion valve, and circulates a refrigerant to
transfer heat from the evaporator to the condenser through heat
exchange.
[0006] FIG. 1 is a diagram schematically illustrating a general
chiller 10.
[0007] As illustrated in FIG. 1, the chiller 10 includes an
evaporator 30, a condenser 20, and a compressor 40. Cold water 31
flows through the evaporator 30, and cooling water 21 flow through
the condenser 20.
[0008] The compressor 40 in which a refrigerant 51, 52 is
circulated connects the evaporator 30 to the condenser 20. The
refrigerant 51 that passes through the evaporator 30 flows into the
compressor 40 through an inlet portion 47 of the compressor 40, and
the refrigerant 52 compressed by two-stage impellers 41 and 42
flows out of an outlet portion 48 of the compressor 40 and then
flows into the condenser 20.
[0009] As illustrated in FIG. 1, in the compressor 40, the
two-stage impellers 41 and 42 are provided on a shaft 43, and the
impellers 41 and 42 are rotated as the shaft 43 is rotated by a
motor 45. Here, gears 44 and 46 are provided to connect the motor
45 to the shaft 43 so as to transmit torque. Although not shown in
the figure, a thrust bearing may be connected between the gear 44
and the shaft 43.
[0010] In the general compressor 40, a load applied to the bearing
increases because a thrust that is transferred to the gears 46 and
44 is focused in one direction, and, thus, a load applied to the
motor 45 also increases. As the load applied to the motor 45
increases, an outlet temperature of the cold water increases, which
results in an increase in head of the compressor. As a result, the
efficiency of the compressor is decreased.
[0011] In order to decrease the head of the compressor and increase
the efficiency of the chiller, a `dual turbo centrifugal chiller`
which includes two chillers connected to each other has been used.
The dual turbo centrifugal chiller has an increased capacity by
increasing the chilling efficiency of the chiller itself. In the
dual turbo centrifugal chiller, two compressors are provided.
However, in the existing dual turbo centrifugal chiller, one of the
two compressors has a higher head than the other. Therefore, the
two compressors have to be independently designed and manufactured.
That is, a driving unit for driving an impeller of each of the
compressors is additionally needed, and the entire size of the
chiller is increased. Accordingly, as described above, there is a
problem in that the efficiency of the compressor is decreased.
SUMMARY
[0012] This disclosure provides a dual turbo centrifugal chiller in
which two compressors, two evaporators, and two condensers are
included to decrease heads of the compressors, the compressors are
configured to operate with the same head, and impellers of the
compressors are driven by a single driving unit, thereby achieving
a decrease in size and an increase in efficiency.
[0013] In one aspect, there is a provided a dual turbo centrifugal
chiller including: first and second evaporators connected in series
or in parallel; first and second condensers connected in series or
in parallel; and first and second compressors including impellers,
wherein cold water passes through the second evaporator after
passing through the first evaporator, and cooling water passes
through the second condenser after passing through the first
condenser, the first compressor containing a refrigerant connects
the first condenser to the second evaporator, and the second
compressor containing a refrigerant connects the second condenser
to the first evaporator, and the impellers of the first compressor
and the second compressor are rotated simultaneously using a single
driving unit.
[0014] In addition, the impellers of the first and second
compressors may be connected with a single rotation shaft, and the
impellers of the first and second compressors may be rotated
simultaneously as the rotation shaft is rotated using the driving
unit.
[0015] In addition, the driving unit may be connected to the center
of the rotation shaft, and the impellers of the first and second
compressors may be opposed with the center of the rotation shaft
between them.
[0016] In addition, inlet portions of the first and second
compressors may be provided with inlet guide vanes (IGVs)
respectively.
[0017] In addition, the first and second compressors may have
different capacities from each other.
[0018] Since the dual turbo centrifugal chiller including the two
evaporators, the two compressors and the two condensers maintains
the reduced head of each compressor, it is possible to achieve the
optimal performance of the compressor.
[0019] In addition, since the impellers of the two compressors are
driven simultaneously using the single driving unit, it is possible
to implement the compressor having a small size and high
efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The above and other aspects, features and advantages of the
disclosed exemplary embodiments will be more apparent from the
following detailed description taken in conjunction with the
accompanying drawings in which:
[0021] FIG. 1 is a diagram schematically illustrating a general
chiller;
[0022] FIG. 2 is a diagram schematically illustrating a dual turbo
centrifugal chiller according to an embodiment; and
[0023] FIG. 3 is a diagram schematically illustrating a dual turbo
centrifugal chiller according to another embodiment.
DETAILED DESCRIPTION
[0024] Exemplary embodiments now will be described more fully
hereinafter with reference to the accompanying drawings, in which
exemplary embodiments are shown. This disclosure may, however, be
embodied in many different forms and should not be construed as
limited to the exemplary embodiments set forth therein. Rather,
these exemplary embodiments are provided so that this disclosure
will be thorough and complete, and will fully convey the scope of
this disclosure to those skilled in the art. In the description,
details of well-known features and techniques may be omitted to
avoid unnecessarily obscuring the presented embodiments.
[0025] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
this disclosure. As used herein, the singular forms "a", "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. Furthermore, the use of the
terms a, an, etc. does not denote a limitation of quantity, but
rather denotes the presence of at least one of the referenced item.
It will be further understood that the terms "comprises" and/or
"comprising", or "includes" and/or "including" when used in this
specification, specify the presence of stated features, regions,
integers, steps, operations, elements, and/or components, but do
not preclude the presence or addition of one or more other
features, regions, integers, steps, operations, elements,
components, and/or groups thereof.
[0026] Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art. It will be further
understood that terms, such as those defined in commonly used
dictionaries, should be interpreted as having a meaning that is
consistent with their meaning in the context of the relevant art
and the present disclosure, and will not be interpreted in an
idealized or overly formal sense unless expressly so defined
herein.
[0027] In the drawings, like reference numerals in the drawings
denote like elements. The shape, size and regions, and the like, of
the drawing may be exaggerated for clarity.
[0028] FIG. 2 is a diagram schematically illustrating a dual turbo
centrifugal chiller 101 according to an embodiment.
[0029] As illustrated in FIG. 2, according to the embodiment, a
first evaporator 121 and a second evaporator 122 are connected in
series. Cold water 123 flows into an end of the first evaporator
121 connected in series, passes through the first evaporator 121,
passes through the second evaporator 122, and then flows out.
[0030] A first condenser 111 and a second condenser 112 are
connected in series. Cooling water 113 passes through the first
condenser 111, flows into the second condenser 112, passes through
the second condenser 112, and then flows out.
[0031] A first compressor 131 is connected to the first condenser
111 and the second evaporator 122 such that a refrigerant of the
first compressor 131 is circulated to exchange heat with the
cooling water 113 of the first condenser 111 and the cold water 123
of the second evaporator 122. A second compressor 132 is connected
to the second condenser 112 and the first evaporator 121 such that
a refrigerant of the second compressor 132 is circulated to
exchange heat with the cooling water 113 of the second compressor
112 and the cold water 123 of the first evaporator 121.
[0032] A temperature of the cold water that flows into the first
evaporator 121 is 12.degree. C., a temperature of the cold water
that flows out of the second evaporator 122 is 7.degree. C., a
temperature of the cooling water that flows into the first
condenser 111 is 32.degree. C., and a temperature of the cooling
water that flows out of the second condenser 112 is 37.degree.
C.
[0033] Without consideration of leaving temperature differences
(LTDs) of the evaporator and the condenser, a head of the first
compressor 131 is 27.5.degree. C. (34.5.degree. C.-7.degree. C.),
and a head of the second compressor 132 is also 27.5.degree. C.
(37.degree. C.-9.5.degree. C.).
[0034] In the dual turbo centrifugal chiller 101 according to the
embodiment, as described above, the heads of the two compressors
131 and 132 are equal to each other. Accordingly, as described
below, a design for simultaneously driving impellers of the two
compressors using a single driving unit may be easily achieved.
[0035] Hereinafter, configurations of the two compressors 131 and
132 according to the embodiment will be described with reference to
FIG. 2.
[0036] According to the embodiment, the first compressor 131 is a
two-stage compression system having two impellers 145 and 146. A
refrigerant 151 flows out of the second evaporator 122 into the
first compressor 131 through an inlet portion 141 of the first
compressor 131, and the refrigerant is compressed while passing
through the impellers 145 and 146. The compressed refrigerant 152
flows out of the first compressor 131 through an outlet portion 142
and flows into the first condenser 111.
[0037] The second compressor 132 is a two-stage compression system
having two impellers 143 and 144. A refrigerant 153 that flows out
of the first evaporator 121 flows into the second compressor 132
through an inlet portion 143 of the second compressor 132, and the
refrigerant is compressed while passing through the impellers 143
and 144. The compressed refrigerant 154 flows out of the second
compressor 132 through an outlet portion 144 and flows into the
second condenser 122.
[0038] According to the embodiment, a single driving unit 163 for
rotating the impellers 143, 144, 145, and 146 of the two
compressors 131 and 132 is provided. In this embodiment, an
electric motor is used as the driving unit 163.
[0039] The impellers 143, 144, 145, and 146 of the two compressors
131 and 132 are connected with a rotation shaft 161. A gear 162 is
provided at the center of the rotation shaft 161, the impellers 145
and 146 of the first compressor 131 and the impellers 143 and 144
of the second compressor 132 are opposed with the center of the
rotation shaft 161 between them. An end portion of the driving unit
163 is connected to a gear, and the gear connected to the driving
unit 163 is engaged with a gear 162 of the rotation shaft 161. In
this configuration, the single driving unit 163 rotates the
rotation shaft 161, and as the rotation shaft 161 is rotated, the
impellers 143, 144, 145, and 146 of the two compressors 131 and 132
are rotated simultaneously.
[0040] According to the embodiment, since the two individual
compressors 131 and 132 are driven by the single driving unit 163,
the entire volume of the compressor system is reduced. Therefore,
the entire size of the dual turbo centrifugal chiller 101 is
reduced.
[0041] In addition, since the impellers of the two compressors are
disposed symmetrically, thrusts applied to both ends of the gear
162 occur in the opposite direction and cancel each other out.
Accordingly, a load applied to a bearing (not shown) used for the
gear 162 decreases, which results in a decrease in the load applied
to the driving unit 163 and an increase in the efficiency of the
driving unit 163. The increase in the efficiency of the driving
unit 163 causes a decrease in the outlet temperature of the cooling
water, and this causes a decrease in the heads of the compressors
131 and 132. Accordingly, there are advantages in that the
efficiency of the entire compression system increases, and the
efficiency of the entire chiller increases. In addition, in
designing the bearing, a design of the bearing without concern
about the thrust applied in particular direction may be
achieved.
[0042] According to the embodiment, the inlet portions of the first
and second compressors 131 and 132 are provided with inlet guide
vanes (IGVs) for adjusting loads applied thereto in order to
facilitate load adjustment.
[0043] According to the embodiment, since the first and second
compressors 131 and 132 are separated from each other, various
combinations of capacity may be attained with the compressors and
the heat exchangers (the condensers and the evaporators). For
example, the capacities of the compressors 131 and 132 may be set
to 1,000 RT and 500 RT, respectively. The size of the heat
exchanger is determined according to the capacity of the
compressor. Even in this case, the impellers of the compressors are
disposed symmetrically on the single rotation shaft, and since the
impellers are disposed symmetrically, the thrust cancellation
effect of the bearing is exhibited even in the case where the
capacities of the two compressors are different from each
other.
[0044] In this embodiment, the two evaporators 121 and 122 are
connected in series, and the two condensers 111 and 112 are
connected in series, however, the embodiment is not limited to that
configuration. Hereinafter, another embodiment will be described
with reference to FIG. 3.
[0045] FIG. 3 is a diagram schematically illustrating a dual turbo
centrifugal chiller 201 according to another embodiment.
[0046] As illustrated in FIG. 3, in the dual turbo centrifugal
chiller 201 according to this embodiment, a first evaporator 221
and a second evaporator 222 are connected in parallel. Cold water
223 flows into an end of the first evaporator 221 connected in
parallel and flows out of the other end of the first evaporator
221, flows into an end of the second evaporator 222, passes through
the second evaporator 222, and flows out of the other end of the
second evaporator 222.
[0047] A first condenser 211 and a second condenser 212 are
connected in parallel. Cooling water 213 flows into an end of the
first condenser 211 connected in parallel, flows out of the other
end of the first condenser 211, flows into an end of the second
condenser 212, passes through the second condenser 212, and flows
out of the other end of the second condenser 212.
[0048] A first compressor 231 is connected to the first condenser
211 and the second evaporator 222, and a refrigerant of the first
compressor 231 is circulated to exchange heat with the cooling
water of the first condenser 211 and the cold water of the second
evaporator 222. A second compressor 232 is connected to the second
condenser 212 and the first evaporator 221, and a refrigerant of
the second compressor 232 is circulated to exchange heat with the
cooling water of the second condenser 212 and the cold water of the
first evaporator 221.
[0049] Here, a temperature of the cold water that flows into the
first evaporator 221 is 12.degree. C., a temperature of the cold
water that flows out of the second evaporator 222 is 7.degree. C.,
a temperature of the cooling water that flows into the first
condenser 211 is 32.degree. C., and a temperature of the cooling
water that flows out of the second condenser 212 is 37.degree.
C.
[0050] Without consideration of LTDs of the evaporators and the
compressors, a head of the first compressor 231 is 27.5.degree. C.
(34.5.degree. C.-7.degree. C.), and a head of the second compressor
232 is also 27.5.degree. C. (37.degree. C.-9.5.degree. C.). That
is, the heads of the two compressors are equal to each other.
[0051] Since connection relationships between impellers 245, 246,
247, and 248 of the compressors 231 and 232, the rotation shaft
161, a gear 262, and a driving unit 263 provided in the dual turbo
centrifugal chiller 201 according to this embodiment, and a flow of
a refrigerant 251, 252, 253, and 254 at inlet and outlet portions
243 and 244 of the compressor are the same as those of the
embodiment illustrated in FIG. 2, a detailed description thereof
will be omitted.
[0052] Although the two embodiments of the dual turbo centrifugal
chiller have been described, this disclosure is not limited
thereto. That is to say, the two evaporators may be connected in
serial or in parallel, and the two condensers may be connected in
serial or in parallel. In this case, it should be understood by
those skilled in the art that cold water passes through a first
evaporator and a second evaporator, cooling water passes through a
second condenser after passing through a first condenser, a first
compressor containing a refrigerant is connected to the first
condenser and the second evaporator, and a second compressor
containing a refrigerant is connected to the second condenser and
the first evaporator, thereby implementing a dual turbo centrifugal
chiller in which heads of the two compressor are equal to each
other.
[0053] While the exemplary embodiments have been shown and
described, it will be understood by those skilled in the art that
various changes in form and details may be made thereto without
departing from the spirit and scope of this disclosure as defined
by the appended claims.
[0054] In addition, many modifications can be made to adapt a
particular situation or material to the teachings of this
disclosure without departing from the essential scope thereof.
Therefore, it is intended that this disclosure not be limited to
the particular exemplary embodiments disclosed as the best mode
contemplated for carrying out this disclosure, but that this
disclosure will include all embodiments falling within the scope of
the appended claims.
* * * * *