U.S. patent application number 16/090902 was filed with the patent office on 2019-05-02 for water-cooled refrigerated transport system.
This patent application is currently assigned to Carrier Corporation. The applicant listed for this patent is Carrier Corporation. Invention is credited to Thomas J. Benedict, Jason D. Scarcella.
Application Number | 20190128568 16/090902 |
Document ID | / |
Family ID | 58664874 |
Filed Date | 2019-05-02 |
United States Patent
Application |
20190128568 |
Kind Code |
A1 |
Scarcella; Jason D. ; et
al. |
May 2, 2019 |
Water-Cooled Refrigerated Transport System
Abstract
A refrigeration system (30) comprises a compressor (36) for
driving the refrigerant along a refrigerant flowpath (34) and
having a first stage (36A) and a second stage (36B). A first heat
exchanger (38) is along the refrigerant flowpath. An intercooler
heat exchanger (120) is along the refrigerant flowpath. A second
heat exchanger (42) is along the refrigerant flowpath. An
additional heat exchanger (170) is along the refrigerant flowpath
between the compressor second stage and the first heat
exchanger.
Inventors: |
Scarcella; Jason D.;
(Cicero, NY) ; Benedict; Thomas J.; (Syracuse,
NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Carrier Corporation |
Palm Beach Gardens |
FL |
US |
|
|
Assignee: |
Carrier Corporation
Palm Beach Gardens
FL
|
Family ID: |
58664874 |
Appl. No.: |
16/090902 |
Filed: |
April 24, 2017 |
PCT Filed: |
April 24, 2017 |
PCT NO: |
PCT/US2017/029103 |
371 Date: |
October 3, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62328206 |
Apr 27, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25B 2400/13 20130101;
F25B 9/008 20130101; F25B 2600/111 20130101; Y02B 30/70 20130101;
F25B 6/04 20130101; Y02B 30/743 20130101; F25B 2339/047
20130101 |
International
Class: |
F25B 6/04 20060101
F25B006/04; F25B 9/00 20060101 F25B009/00 |
Claims
1. A refrigeration system (30) comprising: a compressor (36) for
driving the refrigerant along a refrigerant flowpath (34) having a
first stage (36A) and a second stage (36B); a first heat exchanger
(38) along the refrigerant flowpath; an intercooler heat exchanger
(120) along the refrigerant flowpath, wherein the first heat
exchanger and intercooler heat exchanger are tube and fin heat
exchangers sharing fins (128); a second heat exchanger (42) along
the refrigerant flowpath; and an additional heat exchanger (170)
along the refrigerant flowpath between the compressor second stage
and the first heat exchanger.
2. The refrigeration system of claim 1 wherein: the additional heat
exchanger is a refrigerant-water heat exchanger.
3. The refrigeration system of claim 2 wherein: the system has no
other refrigerant-water heat exchanger.
4. The refrigeration system of claim 1 wherein: the additional heat
exchanger is a brazed plate heat exchanger.
5. The refrigeration system of claim 1 further comprising: a liquid
supply fitting (174) and a liquid return fitting (176) along a
liquid flowpath (172) through the additional heat exchanger.
6. The refrigeration system of claim 1 wherein: the system has no
water-cooled heat exchanger between the first stage and the second
stage.
7. The refrigeration system of claim 1 wherein: the first heat
exchanger and intercooler heat exchanger are in series along an air
flowpath (508).
8. The refrigeration system of claim 1 further comprising: a first
electric fan (50) positioned to drive a first airflow across the
first heat exchanger and the intercooler heat exchanger; and a
second electric fan (52A, 52B) positioned to drive a second airflow
across the second heat exchanger.
9. The refrigeration system of claim 8 being a refrigeration module
mountable to an end of an intermodal container.
10. A refrigerated transport system (20) comprising the
refrigeration system of claim 1 and wherein: the refrigerated
transport system (20) further comprises a body (22) enclosing a
refrigerated compartment; the first heat exchanger is positioned to
reject heat to an external environment in a first cooling mode; and
the second heat exchanger is positioned to absorb heat from the
refrigerated compartment in the first cooling mode.
11. The refrigerated transport system of claim 10, further
comprising: a controller (64) configured to shut off the first
electric fan in response to sufficient sensed water pressure in the
additional heat exchanger.
12. The refrigerated transport system of claim 10 wherein the body
comprises: a pair of side walls (22C, 22D); a top (22A); a bottom
(22B); and one or more doors (28A, 28B).
13. The refrigerated transport system of claim 12, being a
refrigerated intermodal shipping container wherein: the one or more
doors comprise a pair of hinged doors at a first end of the body;
and the refrigeration system is mounted in an equipment box at a
second end of the body opposite the first end.
14. A vessel (600) comprising: a hull (606); a plurality of
refrigerated intermodal shipping containers according to claim 13
in or on the hull; and a cooled water supply system comprising: one
or more heat exchangers (630) positioned to transfer heat between
seawater and a heat transfer fluid; and a supply/return system for
the heat transfer fluid including one or more pumps (642) for
driving a flow of the heat transfer fluid and conduits culminating
in respective supply (180) and return (182) conduits coupled to the
additional heat exchanger.
15. The vessel of claim 14 wherein: the heat transfer fluid is grey
water.
16. A method for operating the refrigeration system of claim 1 the
method comprising in a first mode: running the compressor (36) to
drive the refrigerant along the refrigerant flowpath (34), the
refrigerant passing through the intercooler heat exchanger (120)
between the first stage and the second stage; passing the
refrigerant through the additional heat exchanger (170) to reject
heat from the refrigerant to a fluid flow; passing the refrigerant
through the first heat exchanger (38); and passing the refrigerant
through the second heat exchanger (42) along the refrigerant
flowpath to absorb heat.
17. The method of claim 16 wherein in the first mode: there is no
forced airflow across the first heat exchanger and the intercooler
heat exchanger.
18. The method of claim 16 wherein: in the first mode: the fluid
flow is a water flow.
19. The method of claim 16 further comprising operating in a second
mode comprising: running the compressor (36) to drive the
refrigerant along the refrigerant flowpath (34), the refrigerant
passing through the intercooler heat exchanger (120) between the
first stage and the second stage; passing the refrigerant through
the additional heat exchanger (170); passing the refrigerant
through the first heat exchanger (38) to reject heat; and passing
the refrigerant through the second heat exchanger (42) along the
refrigerant flowpath to absorb heat.
20. The method of claim 19 wherein: in the second mode: the first
mode fluid flow is disabled; and an airflow is driven across the
first heat exchanger and the intercooler
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] Benefit is claimed of U.S. Patent Application No.
62/328,206, filed Apr. 27, 2016, and entitled "Water-Cooled
Refrigerated Transport System", the disclosure of which is
incorporated by reference herein in its entirety as if set forth at
length.
BACKGROUND
[0002] The disclosure relates to refrigerated transport systems
such as intermodal containers. More particularly, the disclosure
relates to such refrigerated transport systems having water-cooled
modes.
[0003] An exemplary refrigerated intermodal container (also known
as a shipping container or intermodal shipping container) has an
equipment module at one end of the container. The equipment module
contains a vapor compression system having a compressor, a heat
rejection heat exchanger downstream of the compressor along a
refrigerant flow path, an expansion device, and a heat absorption
heat exchanger. One or more first fans may drive an external
airflow across the heat rejection heat exchanger. One or more
second fans may drive an internal airflow across the heat
absorption heat exchanger. In various implementations, for powering
the container, there may be a power cord for connecting to an
external power source. For ease of manufacture or service, the
equipment module may be pre-formed as a module mateable to a
remainder of the container body (e.g., insertable into an open
front end of the body). One example of such a container
refrigeration system is sold by Carrier Corporation of Farmington,
Conn. under the trademark NaturaLINE. An example of such a system
is seen in U.S. Patent Application 62/098,144, of Rau, filed Dec.
30, 2014 and entitled "Access Panel", the disclosure of which is
incorporated in its entirety herein as if set forth at length.
Additionally, refrigerated truck boxes, refrigerated railcars, and
the like may have refrigeration systems with different forms or
degrees of modularity.
[0004] Several models of equipment modules are sold with optional
water-cooled condensers (gas coolers for R-744 units). The
water-cooled heat exchanger is located downstream of the air-cooled
heat rejection heat exchanger along the refrigerant flowpath from
the compressor. Water-cooling is used in high ambient temperature
conditions where airflow across the air-cooled heat rejection heat
exchanger is insufficient. One example is ship-board where water is
supplied from a water supply system of the ship that provides
recirculating flows of water and rejects heat to the external
aquatic environment (e.g., seawater). Water cooling is regarded as
an expensive option with a limited market acceptance.
[0005] Also, several models of equipment module have two compressor
stages with intercooling. In an exemplary configuration, the
intercooler heat exchanger is a refrigerant-air heat exchanger
placed downstream of the heat rejection heat exchanger along the
external airflowpath. The NaturaLINE module integrates the
intercooler with the heat rejection heat exchanger in a single
round tube plate fin (RTPF) unit. Water cooling such a unit
presents the additional expense of adding a second
refrigerant-water heat exchanger for intercooling.
SUMMARY
[0006] One aspect of the disclosure involves a refrigeration system
comprising a compressor for driving the refrigerant along a
refrigerant flowpath and having a first stage and a second stage. A
first heat exchanger is along the refrigerant flowpath. An
intercooler heat exchanger is along the refrigerant flowpath. A
second heat exchanger is along the refrigerant flowpath. An
additional heat exchanger is along the refrigerant flowpath between
the compressor second stage and the first heat exchanger.
[0007] In one or more embodiments of any of the foregoing
embodiments, the additional heat exchanger is a refrigerant-water
heat exchanger.
[0008] In one or more embodiments of any of the foregoing
embodiments, the system has no other refrigerant-water heat
exchanger.
[0009] In one or more embodiments of any of the foregoing
embodiments, the additional heat exchanger is a brazed plate heat
exchanger.
[0010] In one or more embodiments of any of the foregoing
embodiments, a liquid supply fitting and a liquid return fitting
are along a liquid flowpath through the additional heat
exchanger.
[0011] In one or more embodiments of any of the foregoing
embodiments, the first heat exchanger and intercooler heat
exchanger are tube and fin heat exchangers sharing fins.
[0012] In one or more embodiments of any of the foregoing
embodiments, the first heat exchanger and intercooler heat
exchanger are in series along an air flowpath.
[0013] In one or more embodiments of any of the foregoing
embodiments, a first electric fan is positioned to drive a first
airflow across the first heat exchanger and the intercooler heat
exchanger and a second electric fan is positioned to drive a second
airflow across the second heat exchanger.
[0014] In one or more embodiments of any of the foregoing
embodiments, the refrigeration system is a refrigeration module
mountable to an end of an intermodal container.
[0015] In one or more embodiments of any of the foregoing
embodiments, a refrigerated transport system comprising the
refrigeration system. The refrigerated transport system further
comprises a body enclosing a refrigerated compartment. The first
heat exchanger is positioned to reject heat to an external
environment in a first cooling mode. The second heat exchanger is
positioned to absorb heat from the refrigerated compartment in the
first cooling mode.
[0016] In one or more embodiments of any of the foregoing
embodiments, a controller is configured to shut off the first
electric fan in response to sufficient sensed water pressure in the
additional heat exchanger.
[0017] In one or more embodiments of any of the foregoing
embodiments, the body comprises: a pair of side walls; a top; a
bottom; and one or more doors.
[0018] In one or more embodiments of any of the foregoing
embodiments, the refrigerated transport system is a refrigerated
intermodal shipping container. The one or more doors comprise a
pair of hinged doors at a first end of the body. The refrigeration
system is mounted in an equipment box at a second end of the body
opposite the first end.
[0019] Another aspect of the disclosure involves a vessel
comprising: a hull; a plurality of the refrigerated intermodal
shipping containers in or on the hull; and a cooled water supply
system. The cooled water supply system comprises: one or more heat
exchangers positioned to transfer heat between seawater and a heat
transfer fluid; and a supply/return system for the heat transfer
fluid including one or more pumps for driving a flow of the heat
transfer fluid and conduits culminating in respective supply and
return conduits coupled to the additional heat exchanger.
[0020] In one or more embodiments of any of the foregoing
embodiments, the heat transfer fluid is grey water.
[0021] In one or more embodiments of any of the foregoing
embodiments, a method for operating the refrigeration system or
refrigerated transport system comprises in a first mode: running
the compressor to drive the refrigerant along the refrigerant
flowpath, the refrigerant passing through the intercooler heat
exchanger between the first stage and the second stage; passing the
refrigerant through the additional heat exchanger to reject heat
from the refrigerant to a fluid flow; passing the refrigerant
through the first heat exchanger; and passing the refrigerant
through the second heat exchanger along the refrigerant flowpath to
absorb heat.
[0022] In one or more embodiments of any of the foregoing
embodiments, there is no forced airflow across the first heat
exchanger and the intercooler heat exchanger.
[0023] In one or more embodiments of any of the foregoing
embodiments, in the first mode the fluid flow is a water flow.
[0024] In one or more embodiments of any of the foregoing
embodiments, the method further comprises operating in a second
mode comprising: running the compressor to drive the refrigerant
along the refrigerant flowpath, the refrigerant passing through the
intercooler heat exchanger between the first stage and the second
stage; passing the refrigerant through the additional heat
exchanger; passing the refrigerant through the first heat exchanger
to reject heat; and passing the refrigerant through the second heat
exchanger along the refrigerant flowpath to absorb heat.
[0025] In one or more embodiments of any of the foregoing
embodiments, in the second mode the first mode fluid flow is
disabled and an airflow is driven across the first heat exchanger
and the intercooler.
[0026] The details of one or more embodiments are set forth in the
accompanying drawings and the description below. Other features,
objects, and advantages will be apparent from the description and
drawings, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a cutaway view of a refrigerated cargo
container.
[0028] FIG. 2 is a rear view of the refrigerated cargo
container.
[0029] FIG. 3 is a schematic view of a refrigeration system of the
refrigerated cargo container.
[0030] FIG. 4 is a front view of a refrigeration unit of the
container of FIG. 1.
[0031] FIG. 5 is a schematic side cutaway view of the refrigerated
cargo container.
[0032] FIG. 6 is a partial view of a subassembly of an air-cooled
condenser/intercooler and water-cooled condenser.
[0033] FIG. 7 is a partial cross-sectional view of the air-cooled
condenser/intercooler taken along line 7-7.
[0034] FIG. 8 is a simplified view of a containerized cargo
ship.
[0035] FIG. 9 is a simplified partial schematic view of a cooling
water supply system of the ship.
[0036] Like reference numbers and designations in the various
drawings indicate like elements.
DETAILED DESCRIPTION
[0037] FIG. 1 shows an intermodal container 20 that may be shipped,
trucked, trained or the like. The container has a body 22 enclosing
an interior 24. The body and interior are formed essentially as
right parallelepipeds. The body has a top 22A, a bottom 22B, a
first side 22C, a second side 22D, a first end 22E and a second end
22F. The top, bottom, and sides may be an integral rigid metallic
structural system. The first end may be closed by an equipment
module 26 ("equipment box"). The second end may essentially be
formed by a pair of oppositely hinged doors 28A, 28B (FIG. 2).
[0038] The exemplary pair of rear doors 28A, 28B (FIG. 2) are
hinged along their outboard edges to the adjacent sides and meet at
their inboard edges. To secure the doors in place, each door has a
pair of vertically oriented locking bars mounted in bushings for
rotation about their central vertical axes. At upper and lower
ends, each of the locking bars has a cam which may interact with an
associated complementary keeper mounted in the rear header and rear
sill respectively. The locking bars may rotate by approximately
90.degree. or up to approximately 180.degree. between a locked
condition wherein the cams interlock with the keepers and an
unlocked condition where the cams may pass free from the keepers as
the doors are rotated between their opened and closed
conditions.
[0039] The equipment module contains a vapor compression
refrigeration system 30 (FIG. 3). The exemplary system uses a
carbon dioxide based refrigerant such as R-744. The illustrated
example comprises, sequentially along a main portion of a
refrigerant flowpath 34, a compressor 36, a heat rejection heat
exchanger 38, an expansion device 40 (e.g., electronic expansion
valve, thermal expansion valve, orifice, or the like), and a heat
absorption heat exchanger 42. One or more first fans 50 may drive
an external airflow 520 across the heat rejection heat exchanger.
The heat rejection heat exchanger is thus referred to as an
air-cooled condenser (ACC). The term "condenser" is used in the art
in a broad sense to comprehend both true condensers and gas
coolers. One or more second fans 52A, 52B (FIGS. 3 and 4) may drive
an internal airflow 522A, 522B along respective flowpaths 510A,
510B across the heat absorption heat exchanger.
[0040] In various implementations, for powering the container,
there may be a power cord (not shown) for connecting to an external
power source. For example, the external power source may be from
the ship or truck-trailer carrying the container or may be from a
facility or yard in which the container is stored. Additionally,
the container may be associated with a generator 60 (FIG. 3, e.g.,
having an internal combustion engine). For intermodal containers,
the generator may be a part of an accessory "genset" that may
separately mount to a vehicle (trailer or rail car) carrying the
container. Other transport refrigeration systems such as dedicated
trailers may integrate the generator into an equipment body mounted
to the front of the trailer box. The refrigeration system may
include a main controller 64 (e.g., having a processor, memory and
storage for running a program to perform the required functions)
powered by a main battery 66. The battery is typically a
rechargeable battery that charges when the container is plugged
into external power or a running genset.
[0041] For ease of manufacture or service, the equipment module may
be pre-formed as a module mateable to a remainder of the container
body (e.g., insertable into an open front end of the body).
[0042] The module 26 comprises a front panel or panel assembly 70
(FIG. 4). In FIGS. 1 and 4, a lower right (in the drawing; left on
the container) panel of the assembly 70 is shown cut away. To the
left side of the drawing, lower panels are removed to expose
various components. The panel assembly 70 may have a plurality of
openings of which some may be closed by various means. Two of the
openings are along the respective air flowpaths 510A, 510B of the
two evaporator fans 52A and 52B. These flowpaths may be isolated
from each other or may merely be adjacent halves of a single
flowpath (or may be a combination, separating and merging). In this
example, the opening spans the fan, so that a portion of the
opening is upstream of the fan and a portion of the opening is
downstream. The openings are closed by respective access panels
80A, 80B (FIG. 4). The exemplary panel 80A includes a rotary gate
valve (e.g., manual or motorized) for venting for fresh air
exchange. It may also have a small blower fan 81A to withdraw air
from the flowpath 510A (or may rely on leakage across the adjacent
evaporator fan). Other valve/gate structures may be provided. The
illustrated panel 80B lacks any vent/valve and/or blower but may
also have one.
[0043] The exemplary system 30 is an economized system. An
exemplary economized system has the compressor as a two-stage
compressor having respective first and second stages 36A and 36B.
In the exemplary embodiment, the first stage 36A and the second
stage 36B are, respectively, a low pressure stage and a high
pressure stage. The exemplary stages are commonly powered by a
motor 37. For example, the stages may be separate cylinder banks of
a reciprocating compressor. FIG. 3 shows the compressor having an
overall suction port 90 and an overall discharge port 92. An
economizer port is labeled 94. An exemplary economizer involves a
flash tank economizer subsystem 100 located between the heat
rejection heat exchanger 38 and the expansion device 40. The
exemplary system 100 comprises a flash tank 102 having a liquid
outlet 104 for feeding the expansion device 40 and a vapor outlet
106 for feeding saturated vapor along an economizer line 108 to the
economizer port 94. Typically the mixing of saturated vapor helps
cool (lower) the temperature of the refrigerant leaving the first
stage. This and the intercooler together serve to lower that
temperature to keep the second stage temperature (the discharge
temperature) from getting too high. An economizer expansion device
110 may be integrated with the flash tank or upstream of an inlet
112 of the flash tank. The exemplary expansion device 110 is a
conventional high pressure expansion valve.
[0044] The exemplary refrigeration system is also an intercooled
system having an intercooler heat exchanger 120. The intercooler
heat exchanger may, in at least some operational modes, be between
the first stage 36A and second stage 36B along the refrigerant
flowpath. The exemplary intercooler heat exchanger (intercooler)
120 is a refrigerant-air heat exchanger. The exemplary
refrigerant-air heat exchanger is along the external air flowpath
508. In the exemplary embodiment, the intercooler heat exchanger
120 is downstream of the heat rejection heat exchanger 38 along
said flowpath 508. As is discussed further below, the heat
exchangers 38 and 120 may be integrated in a single air-cooled
condenser/intercooler unit 121 (FIG. 6) with separate tube legs 124
associated with the heat exchanger 38 and 126 associated with the
heat exchanger 120. The exemplary combined unit is a fin-tube heat
exchanger (e.g., round tube plate fin (RTPF)) wherein metallic fins
128 and tube sheets are shared by both sets of tube legs. Other
configurations may intermix tubes and the exact balance of tubes
associated with the respective legs may be dictated by various
performance factors.
[0045] The intercooler is located along an interstage line 130
(FIG. 3) forming an interstage leg 34-1 of the flowpath 34. The
interstage line extends from a port 134 on the compressor. In the
exemplary intercooled and economized embodiment, the intercooler
line 130 merges with the economizer line 108 such that the
intercooler refrigerant flow may return to the second stage via the
economizer port 94.
[0046] FIG. 3 shows a number of additional features that may be
conventional in a baseline economized and intercooled system. These
include a valve 140 along the economizer line (e.g., an economizer
solenoid valve) which may selectively permit and block the
economizer flow. A check valve 142 along the economizer line
prevents reverse flow through the port 106. An unloading valve 144
(e.g., an unloader solenoid valve) is positioned along an unloading
line 146 extending from the second stage inlet (economized port)
condition back to the first stage inlet (suction port 90)
condition. In the exemplary embodiment, this is shown extending
between a junction of the lines 108 and 130 and a suction line
upstream of the suction port 90. Physical arrangements other than
those illustrated may achieve the same fluidic conditions.
[0047] Among other conventional features are a filter/dryer 150, a
high side charging port 152, a low side charging port 153, a low
side pressure relief valve 154, a high side pressure relief valve
156, various pressure sensors 158, various temperature sensors 160,
and a flash tank pressure relief valve 162.
[0048] To the exemplary baseline refrigeration system, the system
30 adds a water-cooled heat rejection heat exchanger 170 (aka,
water-cooled condenser) upstream of the heat rejection heat
exchanger 38 along the refrigerant flowpath. The heat exchanger 170
places a water flowpath 172 in heat exchange relation with the
refrigerant flowpath. Although the term "water" is used, as a
practical matter, flow in the flowpath 172 will typically not be
pure water but may have one or more of various additives for
bacterial control, corrosion inhibition, freeze protection, pump
lubrication, and the like. This water is identified in the art as
"grey water". FIG. 3 shows an inlet fitting 174 and an outlet
fitting 176 along the flowpath 172. A water pressure sensor 178 may
be long the flowpath 172 somewhere between the fittings. As is
discussed below, these may be connected to respective supply 180
and return 182 lines via respective fittings 184, 186 (e.g.,
self-draining quick-connect fittings) to supply cool water and
return warmed water. To prevent misconnection, the fittings 174 and
176 may differ from each other such as being of opposite sex.
[0049] The system 30 may have one or more non-water-cooled modes
wherein there is no flow along the flowpath 172. These may include
one or more economized modes and one or more non-economized
modes.
[0050] The system 30 also has at least one mode wherein there is
water flow along the flowpath 172. As is discussed below, this will
occur, for example, when the container is on a ship. With
containers stacked on in a ship, inlet airflow along the flowpath
508 may be of relatively warm air due to poor circulation. Absent
rejection of heat via the heat exchanger 170, the system 30 may be
unable to cool the container under those circumstances. Similarly,
otherwise extreme outdoor temperatures may overpower the basic
capacity of the system. In such situations, flow along the flowpath
170 pre-cools the refrigerant entering the heat exchanger 38.
Depending on circumstances, this cooling may be to a temperature
below ambient air temperature.
[0051] In general, control may reflect existing control protocols
for water-cooled refrigerated containers and economized/intercooled
containers generally. As in a conventional water-cooled system, the
pressure sensor 178 may be used by the controller to determine when
to switch to water-cooled modes. When threshold water pressure is
sensed, the controller may shut off power to the condenser fan 50
while continuing to run the compressor, evaporator fan(s), and
other components as normal. When water pressure is not sensed, the
controller will operate the condenser fans as normal.
[0052] Cooling of refrigerant entering the heat exchanger 38 allows
indirect cooling of refrigerant passing along the intercooler
flowpath 34-1. For example, instead of rejecting heat to the
airflow 520, the heat exchanger 38 may absorb heat from the airflow
520 and allow the intercooler heat exchanger 120 to, in turn,
reject heat to the airflow 520. Another mechanism or dynamic is via
direct thermal conduction of heat from the intercooler heat
exchanger to the heat exchanger 38. For example, as was noted
above, the heat exchangers 38 and 120 may be two sections of a
single physical unit. For example, the single unit may be a plate
fin heat exchanger wherein the two sections are formed by different
individual tube legs 124, 126 (FIG. 7) but sharing fins 128. The
fins may conduct heat from the tubes of the intercooler heat
exchanger section to the tubes of the heat exchanger section 38. In
such a situation, the fan 50 may be shut off to prevent the airflow
520. It is thus seen that by positioning the water-cooled condenser
170 upstream of the air-cooled condenser 38, the water-cooled
condenser 170 can provide direct cooling of refrigerant along the
main flowpath and indirect cooling of refrigerant along the
intercooler flowpath to allow intercooled operation in a
water-cooled mode. This avoids, for example, the need to provide a
second water cooled heat exchanger along the intercooler flowpath
34-1.
[0053] FIG. 8 shows a cargo ship 600 carrying a plurality 602 of
containers stacked topside and a plurality 604 of containers within
a compartment in the interior of the hull 606 of the ship.
Schematically, a cooling water system 618 on the ship comprises a
seawater side 620 including one or more inlet ports 622 for drawing
in seawater and one or more discharge ports 624 for discharging
seawater. One or more pumps 626 may drive a flow of seawater from
the inlet(s) to the outlet(s) and through the seawater side of one
or more water-water heat exchangers 630. On a grey water side 640,
one or more pumps 642 drive flow through the grey water side(s) of
a heat exchanger(s) 630. Various supply and return manifold
structures 660, 662 may ultimately culminate in the individual
supply 180 and return 182 lines for the individual containers.
Other details such as various filters, sterilizers, expansion
tanks/buffers, and the like are not shown but may be included as
are known or yet to be developed in the art.
[0054] The system may be made using otherwise conventional or
yet-developed materials and techniques.
[0055] The use of "first", "second", and the like in the
description and following claims is for differentiation within the
claim only and does not necessarily indicate relative or absolute
importance or temporal order. Similarly, the identification in a
claim of one element as "first" (or the like) does not preclude
such "first" element from identifying an element that is referred
to as "second" (or the like) in another claim or in the
description.
[0056] One or more embodiments have been described. Nevertheless,
it will be understood that various modifications may be made. For
example, when applied to an existing basic refrigeration system
and/or container construction and associated use methods, details
of such existing configuration or its associated use may influence
details of particular implementations. Accordingly, other
embodiments are within the scope of the following claims.
* * * * *