U.S. patent application number 16/326096 was filed with the patent office on 2019-07-11 for arrangement, particularly refrigerating machine or heat pump.
The applicant listed for this patent is Mahle International GmbH. Invention is credited to Roland Burk.
Application Number | 20190212071 16/326096 |
Document ID | / |
Family ID | 59745244 |
Filed Date | 2019-07-11 |
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United States Patent
Application |
20190212071 |
Kind Code |
A1 |
Burk; Roland |
July 11, 2019 |
ARRANGEMENT, PARTICULARLY REFRIGERATING MACHINE OR HEAT PUMP
Abstract
An arrangement may comprise a first and second heat tank, a
thermochemical reactor that is thermally and fluidically connected
to the heat tank, a heat transfer fluid circuit containing a heat
transfer fluid for transporting heat between the two heat tanks and
the thermochemical reactor, a temporary heat store arranged in the
heat transfer fluid circuit for the temporary storage of the heat
transfer fluid. The temporary heat store may be designed to receive
the heat transfer fluid at two different temperature levels. The
temporary heat store may include a first partial store with
variable storage space and a second partial store with variable
storage space.
Inventors: |
Burk; Roland; (Stuttgart,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mahle International GmbH |
Stuttgart |
|
DE |
|
|
Family ID: |
59745244 |
Appl. No.: |
16/326096 |
Filed: |
August 16, 2017 |
PCT Filed: |
August 16, 2017 |
PCT NO: |
PCT/EP2017/000982 |
371 Date: |
February 15, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28D 20/0034 20130101;
F25B 17/08 20130101; Y02B 30/64 20130101; F28D 2020/0095 20130101;
Y02E 60/14 20130101; F25B 2400/24 20130101; Y02A 30/278 20180101;
F25B 30/04 20130101; Y02B 30/00 20130101; Y02A 30/27 20180101; Y02E
60/142 20130101 |
International
Class: |
F28D 20/00 20060101
F28D020/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 17, 2016 |
DE |
102016215381.1 |
Claims
1. A system for an arrangement of a refrigerating machine or a heat
pump, comprising: a first heat reservoir acting as a heat source
and with a second heat reservoir acting as a heat sink, at least
one thermochemical reactor configured to be thermally and
fluidically connected to the heat reservoirs, a heat transfer fluid
circuit, in which a heat transfer fluid is arranged to transport
heat between the two heat reservoirs and the at least one
thermochemical reactor, a temporary heat store arranged in the heat
transfer fluid circuit for temporarily storing the heat transfer
fluid, wherein the temporary heat store is designed to hold the
heat transfer fluid with two different stratified temperature
distributions between the temperatures of the heat reservoirs
(T.sub.1, T.sub.2), and, for this purpose, the temporary heat store
has a first partial store with a variable storage volume and has a
second partial store with a variable storage volume that is
thermally and fluidically separated from this, at least one,
preferably two conveying device(s) available in the heat transfer
fluid circuit to propel the heat transfer fluid (F) in the heat
transfer fluid circuit, a valve system available in the heat
transfer fluid circuit, which comprises at least one adjustable
valve device, by which the heat transport between the two heat
reservoirs, the thermochemical reactor and the temporary heat store
can be controlled by the heat transfer fluid, a regulating/control
system for controlling the valve system.
2. The system according to claim 1, at least two thermochemical
reactors are available, which each comprise a separate housing, a
fluid inlet, and a fluid outlet, wherein the at least two
thermochemical reactors are fluidically connected to each other in
parallel.
3. The system according to claims 1, wherein the valve system
comprises a first adjustable valve device for each available
thermochemical reactor, by which the fluid inlet of the respective
thermochemical reactor can be optionally connected to the first or
the second heat reservoir, and the valve system comprises a second
adjustable valve device for each available thermochemical reactor,
by which the fluid outlet of the respective thermochemical reactor
can be optionally connected to the first or the second heat
reservoir.
4. The system according to one of the claim 1, wherein the
regulation/control device is set up or programmed for the
time-delayed adjustment of the individual first valve devices and
for the time-delayed adjustment of the individual second valve
devices.
5. The system according to claim 1, further comprising an
equalizing reservoir arranged in the heat transfer fluid circuit to
hold the heat transfer fluid.
6. The system according to claim 1, wherein the first valve devices
and the second valve device are each designed as a 3/2-way
switching valve.
7. The system according to claim 6, wherein at least a 3/2-way
valve is designed as an automatically switching valve.
8. The system according to claim 1, wherein the temporary heat
store is fluidically connected in parallel with the second valve
directions so that the fluid inlet of the first heat reservoir
fluidically communicates with the first partial store and the fluid
inlet of the second heat reservoir fluidically communicates with
the second partial store.
9. The system according to claim 1, wherein the temporary heat
store is designed to simultaneously hold and output a first and a
second fluid mass of the heat transfer fluid, and wherein both
fluid masses have different temperature levels or temperature
stratifications.
10. The system according to claim 1, wherein the first partial
store of the temporary heat store is fluidically connected to the
first heat reservoir and the second partial store of the temporary
heat store is fluidically connected to the second heat
reservoir.
11. The system according to claim 1, wherein the volume-variable
first partial store is designed to be complementary to the
volume-variable second partial store so that the overall volume
formed by the two partial stores is constant.
12. The system according to claim 1, wherein the temporary heat
store is designed as a reservoir, wherein the reservoir comprises:
a housing, in the interior space of which a separation element is
movably arranged, which divides the interior space into a
volume-variable first partial store and a second partial store,
which is also volume-variable and their medically insulated from
the first partial store, a first through-opening available in the
housing for introducing and discharging a heat transfer fluid with
a first temperature level or a temperature stratification
subsequent to it into or out of a first partial store, and a second
through-opening available in the housing for introducing and
discharging a heat transfer fluid with a second temperature level
or a temperature stratification subsequent to it into or out of a
second partial store, wherein the volume-variable first partial
store is designed to be complementary to the volume-variable second
partial store so that the overall volume formed by the two partial
stores is constant.
13. The system according to claim 12, wherein a first sensor
element is provided on the first through-opening, by which, it can
be determined whether the separation element is located in a first
end position, in which the separation element has a minimum
distance away from the first through-opening and/or that a second
sensor element is provided on the second through-opening, by which,
it can be determined whether the separation element is located in a
second end position, in which the separation element has a minimum
distance away from the second through-opening.
14. The system according to claim 13, wherein an operating state
can be set by the regulation/control device in the at least one
adjustable valve device of the valve system, in which the heat
transfer fluid circuit forms a first partial circuit and in which
the heat transfer fluid transports heat between the thermochemical
reactor and the second heat reservoir so that heat is transferred
from the thermochemical reactor into the second heat reservoir.
15. The system according to claim 14, wherein, in the operating
state, the first partial store has a maximum volume and the second
partial store has a minimum volume.
16. The system according to claim 1, wherein an operating state can
be set by the regulation/control device in the at least one
adjustable valve device of the valve system where, in which the
heat transfer fluid circuit forms a second partial circuit, in
which the heat transfer fluid transports heat between the
thermochemical reactor and the first heat reservoir so that heat is
transferred from the first heat reservoir into the thermochemical
reactor.
17. The system according to claim 16, wherein, in the operating
state, the second partial store has a maximum volume and the first
partial store has a minimum volume.
18. The system according to claim 1, wherein an operating state can
be set by the regulation/control device in the at least one
adjustable valve device of the valve system wherein: heat transfer
fluid is transported from the first partial store into the first
heat reservoir, heat transfer fluid is transported from the first
heat reservoir into the thermochemical reactor, and heat transfer
fluid is transported from the thermochemical reactor into the
second partial store.
19. The system according to claim 1, wherein an operating state can
be set by the regulation/control device in the at least one
adjustable valve device of the valve system, wherein: heat transfer
fluid is transported from the second partial store into the second
heat reservoir, heat transfer fluid is transported from the second
heat reservoir into the thermochemical reactor, and heat transfer
fluid is transported from the thermochemical reactor into the first
partial store.
20. A method to operate an arrangement of a heat transfer fluid
circuit comprising: providing at least one thermochemical reactor,
two heat reservoirs with different temperature levels (T.sub.1,
T.sub.2) and a temporary heat store, wherein the temporary heat
store comprises two thermally and fluidically separated partial
stores, in which a heat transfer fluid available in the heat
transfer fluid circuit can be taken on being thermally a
fluidically separated from one another; supplying heat from the
first heat reservoir into the thermochemical reactor by taking heat
transfer fluid temporarily stored in the first partial store of the
temporary heat store and supplying heat transfer fluid to the first
heat reservoir and, at the same time, dissipating heat transfer
fluid from the thermochemical reactor and introducing the heat
transfer fluid into the second partial store of the temporary heat
store; and dissipating heat from the at least one thermochemical
reactor into the second heat reservoir, by taking heat transfer
fluid temporarily stored in the second partial store of the heat
transfer fluid and supplying heat transfer fluid to the second heat
reservoir and, at the same time, dissipating heat transfer fluid
from the thermochemical reactor and introducing heat transfer fluid
into the first partial store of the temporary heat store.
21. The method according to claim 20, wherein at least two
thermochemical reactors are available, which each comprise a
separate housing, a fluid inlet, and a fluid outlet, wherein the at
least two thermochemical reactors are fluidically connected to each
other in parallel, the valve system comprises a first adjustable
valve device for each available thermochemical reactor, by which
the fluid inlet of the respective thermochemical reactor can be
optionally connected to the first or the second heat reservoir, the
valve system comprises a second adjustable valve device for each
available thermochemical reactor, by which the fluid outlet of the
respective thermochemical reactor can be optionally connected to
the first or the second heat reservoir, wherein, in accordance with
switching the first existing valve devices to connect the
thermochemical reactors to the first or the second heat reservoir
takes place in a time-delayed manner, and wherein, in accordance
with switching the first existing valve devices to connect the
thermochemical reactors to the first or the second heat reservoir
takes place in a time-delayed manner.
22. The method according to claim 21, wherein the time-delayed
switching of the first and the second valve devices takes place in
such a way that at least one of the thermochemical reactors and a
maximum of two of the available thermochemical reactors
simultaneously have the temperature level of the first heat
reservoir.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to International
Application PCT/EP2017/000982 filed on Aug. 16, 2017 and to German
Application DE 10 2016 215 381.1 filed on Aug. 17, 2016, the
contents of each are hereby incorporated by reference in their
entirety.
TECHNICAL FIELD
[0002] The invention relates to an arrangement, in particular, a
refrigerating machine or a heat pump, as well as a method for
operating this arrangement.
[0003] Thermally powered sorption refrigerating systems have a high
energy savings potential since inexpensive waste or excess heat is
used and, in this way, expensive mechanical drive energy can be
saved. In the case of stationary applications, the electrical
networks can be relieved, particularly in warm time zones and
climate zones with a high level of cooling demand. In the cold
season, the systems can also be used as heat pumps, which boost
additional environmental heat to a temperature level sufficient for
heating purposes by means of burner heat.
BACKGROUND
[0004] Against this background, from the most recent background
art, apparatuses are known where porous solid materials are used,
which react with a working material subject to the implementation
of heat and do not have any moving and thereby fault-prone wear
parts within the range of the working material.
[0005] However, with relation to continuously working absorption
systems, adsorption heat pumps or adsorption refrigerating systems
implemented with the aid of such thermochemical reactors have the
disadvantage that the periodic temperature changes with cycled
thermal masses result in efficiency compromises, which reduce the
achieved power density or power efficiency.
[0006] In this context, DE 102006043715 A1 discloses an adsorption
heat pump where a stratified heat store is used. This allows for a
time-delayed storage and reuse of sensitive and latent heat during
the adsorption cycle. However, such stratified heat stores cannot
be used everywhere due to its great volume.
[0007] It is the object of the present invention to indicate new
ways to develop sorption heat pumps and sorption refrigeration
systems, in particular, having improved efficiency.
[0008] This task is achieved by means of the object of the
independent patent claims. Favourable embodiments are the object of
the dependent patent claims.
SUMMARY
[0009] The basic idea of the invention is to equip an arrangement
of an adsorption heat pump or an adsorption refrigerating machine
based on cyclically operating thermochemical reactors with a
temporary heat store, which has two partial stores to hold a heat
transfer fluid at two different temperature levels. This temporary
heat store is used to temporarily store heat contained in the heat
transfer fluid in the case of thermally cycling the thermochemical
reactor and in the case of switching the thermochemical reactor
between two different temperature levels associated therewith.
Under the term "thermochemical reactor", in general, a reservoir
with at least one working material and one integrated heat transfer
structure is understood, using with at least on exothermic or
endothermic reaction or phase change can be instigated
independently of a marginal temperature condition subject to the
supply and dissipation of heat. Thereby, it can have to do with a
sorption reactor or a phase changer, in particular, a condenser
and/or a vaporiser. Such special embodiments, components or
subcomponents are also known under the terms "sorber", "sorption
reactor", "thermochemical store" or "phase changer".
[0010] The present temporary heat store according to the invention
that is used allows for the temporary storage of the heat transfer
fluid at the temperature level of a heat source of the arrangement
in the first partial store and the simultaneous temporary storage
of the heat transfer fluid at the temperature level of a heat sink
of the arrangement in the second partial store of the temporary
heat store.
[0011] In the case of the temporary heat store according to the
invention, a volume reduction of the second partial store is
associated with a volume increase of the first partial store and
vice versa. Since both volume-variable partial stores comprise the
same overall volume, introducing the heat transfer fluid at the
temperature level of the heat source into the first subspace makes
discharging the heat transfer fluid at the second temperature level
from the second partial store easier and vice versa. In this way,
undesired energy loss of the thermochemical reactor during thermal
cycling, meaning when switching over between the two temperature
levels of the heat source and the heat sink can be minimized. In
the result, this leads to an improved efficiency of the arrangement
according to the invention with relation to conventional
arrangements.
[0012] An arrangement according to the invention, in particular, a
refrigerating machine or a heat pump, comprises a first heat
reservoir, which acts as a heat source as well as a second heat
reservoir, which acts as a heat sink. The arrangement furthermore
comprises at least one thermochemical reactor, which is or can be
thermally and fluidically connected to the heat reservoirs.
Preferably, the thermochemical reactor is an adsorption
refrigerating machine or an adsorption heat pump or is a crucial
functional component thereof.
[0013] Furthermore, the arrangement comprises a heat transfer fluid
circuit, in which a heat transfer fluid is arranged to transport
heat between the two heat reservoirs and the thermochemical
reactor. A temporary heat store is provided in the heat transfer
fluid circuit to temporarily store the heat transfer fluid.
According to the invention, the temporary heat store comprises a
first partial store with a variable storage volume. Furthermore,
the temporary heat store comprises a second partial store with a
variable storage volume that is thermally and fluidically separated
from the first partial store.
[0014] At least one, preferably two conveying device(s) of the
arrangement according to the invention available in the circuit is
used to propel the heat transfer fluid in the heat transfer fluid
circuit. Furthermore, the arrangement comprises a valve system that
is available in the heat transfer fluid circuit and comprises at
least one adjustable valve device. By means of this at least one
adjustable valve device, the heat transport between the two heat
reservoirs, the thermochemical reactor and the temporary heat store
can be controlled by means of the heat transfer fluid. For
controlling the said valve system, the arrangement according to the
invention only comprises a regulation/control device.
[0015] In a preferred embodiment, at least two thermochemical
reactors are provided, which each comprise a separate reservoir
with a heat transfer structure with a fluid inlet and a fluid
outlet. The at least two thermochemical reactors are thereby
arranged with a fluidic parallel connection to one another, meaning
the fluid inlets and the fluid outlets of the at least two
thermochemical reactors are or can be fluidically connected to each
other by means of the valve system. The provision of two or a
greater number of separate thermochemical reactors allows for a
time-delayed switching of the available thermochemical reactors
from a state with a higher temperature T.sub.1 into a state with a
temperature T.sub.2 that is relatively lower than temperature
T.sub.1. The time-delayed switching of the individual
thermochemical reactors results in a particularly low energy loss
during the temperature change in connection with the temporary heat
store.
[0016] In the case of a favourable further embodiment, the valve
system comprises a first adjustable valve device for each available
thermochemical reactor, by means of which the fluid inlet of the
respective thermochemical storage can be optionally connected to
the first or the second heat reservoir. In the case of this
variant, the valve system comprises a second adjustable valve
device for each available thermochemical reactor, by means of which
the fluid outlet of the respective thermochemical reactors can be
optionally connected to the first or the second heat reservoir.
This measure allows for a favourable control of the time-delayed
switching process between exothermic and endothermic subprocesses
running at different temperature levels.
[0017] Being particularly preferred, the regulation/control device
is set up/programmed for the time-delayed adjustment of the
individual first valve devices and for the time-delayed adjustment
of the individual second valve devices. This means that the
regulation/control device is capable of adjusting the first and
second valve devices via suitable control lines individually,
meaning independently of one another. The regulation/control device
can comprise a control unit or a storage unit. In the latter, a
computer programme code can be stored, which is processed by the
control unit to carry out the time-delayed switching process of the
individual first and second valve devices. In the said computer
program code, the algorithm for the time-delayed switching of the
first and the second valve devices is thereby coded.
[0018] Expediently, the temporary heat store is fluidically
connected in parallel to the second valve devices in such a way
that the fluid inlet of the first heat reservoir fluidically
communicates with the first partial store and the fluid inlet of
the second heat reservoir fluidically communicates with the second
partial store.
[0019] In a favourable further embodiment, the first valve device
and the second valve device each comprise a 3/2-way valve. This
allows for a simple implementation of an optional fluidic
connection of the at least one thermochemical reactor either with a
first heat reservoir at temperature level T.sub.1 or the second
heat reservoir at temperature level T.sub.2.
[0020] In another preferred embodiment, an equalizing reservoir is
arranged in the heat fluid circuit to hold the heat transfer
fluid.
[0021] In the case of another preferred embodiment, the temporary
heat store is designed to simultaneously hold and output a first
and a second fluid mass of the heat transfer fluid, wherein the two
fluid masses can have various temperature stratifications between
the temperature limits T.sub.1 and T.sub.2. This makes it possible
to simultaneously temporarily store fluid mass within the temporary
heat store for carrying out an energy-efficient temperature change
between the temperature level of the heat sink and the heat
source.
[0022] Being particularly favourable, the first partial store of
the temporary heat store is fluidically connected to the first heat
reservoir and the second partial store of the temporary heat store
is fluidically connected to the second heat reservoir.
[0023] This measure allows for a simple supply of heat transfer
fluid near the temperature T.sub.1 from a thermochemical reactor to
be cooled into the temporary heat store. This measure also allows
for a simple supply of heat transfer fluid near the temperature
T.sub.2 from a thermochemical reactor to be heated into the
temporary heat store.
[0024] In accordance with a particularly preferred embodiment, the
temporary heat store is designed as a reservoir. In the case of
this variant, the reservoir comprises a housing, in the interior
space of which a separation element is movably arranged, which
divides the interior space into a volume-variable first partial
store and a second partial store, which is also volume-variable and
is thermally insulated from the first partial store. A first
through-opening is provided in the housing for the introduction and
discharge of the heat transfer fluid into the or from the first
partial store. Furthermore, a second through-opening is provided in
the housing for the introduction and discharge of the heat transfer
fluid into the or from the second partial store.
[0025] In the case of a favourable further embodiment, the housing
is designed to be oblong. Thereby, the first through-opening is
arranged on a first longitudinal end and the second through-opening
is arranged on a second longitudinal end situated opposite to the
first longitudinal end. The large length/sectional ratio associated
with an oblong shape of the housing serves the purpose that a
temperature stratification of the fluid mass flowing in and out
remains constant to a great extent and does not notably mix during
the required storage time.
[0026] Expediently, the housing can be designed as a pipe body,
which essentially extends in a straight line along an axial
direction. In the case of this variant, the separation element
abuts the inner side of a circumferential wall of the pipe body to
form the two volume-variable partial stores along the axial
direction in a moveable manner. Such a construction is easy to
manufacture on a technical level, thereby being associated with low
manufacturing costs.
[0027] In another favourable further embodiment, a first sensor
element is provided on the first through-opening, by means of which
it can be determined whether the separation element is situated in
a first end position, in which the separation element has a minimum
distance away from the first through-opening. In addition or as an
alternative, in the case of this variant, a second sensor element
can be provided on the second through-opening, by means of which it
can be determined whether the separation element is situated in a
second end position, in which the separation element has a minimum
distance away from the second through-opening. In this way, in the
case of thermal cycling the thermochemical reactor, it can be
determined when the heat transfer fluid has been completely taken
from the two partial stores, because, in this case, the separation
element is situated at a minimum distance away from the first or
the second through-opening.
[0028] In the case of a preferred embodiment of the arrangement, an
operating state can be set by the regulation/control device in the
at least one adjustable valve device of the valve system, in which
the heat transfer fluid circuit forms a first partial circuit. In
this first partial circuit, the heat transfer fluid circulates
between the thermochemical reactor and the second heat reservoir,
and that being in such a way that heat is transferred from the
thermochemical reactor into the second heat reservoir, meaning into
the heat sink. In this way, heat can be dissipated from the
thermochemical reactor in a particularly effective way.
[0029] Preferably, in this operating state, the first partial store
has a maximum volume and the second partial store has a minimum
volume. This means that the first partial store is filled with the
heat transfer fluid, which has a temperature stratification near
the temperature level of the heat source.
[0030] In the case of another preferred embodiment of the
arrangement, an operating state can be set by the
regulation/control device in the at least one adjustable valve
device of the valve system, in which the heat transfer fluid
circuit forms a second partial circuit. In this second partial
circuit, the heat transfer fluid circulates between the
thermochemical reactor and the first heat reservoir so that heat is
transferred from the first heat reservoir, meaning from the heat
source, into the thermochemical reactor.
[0031] Preferably, in this operating state, the second partial
store has a maximum volume and the second partial store has a
minimum volume. This means that the second partial store is filled
with the heat transfer fluid, which has a temperature
stratification near the temperature level of the heat sink.
[0032] In the case of another preferred embodiment of the
arrangement, an operating state can be set by the
regulation/control device in the at least one adjustable valve
device of the valve system where heat transfer fluid is transported
from the first partial store of the temporary heat store into the
first heat reservoir. At the same time, heat transfer fluid from
the first heat reservoir is transported into the thermochemical
reactor and heat transfer fluid is transferred from the
thermochemical reactor into the second partial store. In this way,
heat can be supplied to the thermochemical reactor in a
particularly effective manner and, thereby, the sensitive heat with
a lower temperature can be stored for a later cooling process.
[0033] In the case of another preferred embodiment of the
arrangement, and operating state can be set by the
regulation/control device in the at least one adjustable valve
device of the valve system where heat is transferred from the
second partial store into the second heat reservoir by means of the
heat transfer fluid. At the same time, heat from the second heat
reservoir is transported into the thermochemical reactor and from
the thermochemical reactor into the first partial store by means of
the heat transfer fluid. In this way, heat can be discharged from
the thermochemical reactor in a particularly efficient manner and,
thereby, the sensitive heat with a higher temperature can be stored
for a later heating process.
[0034] In a favourable further embodiment, the first and the second
heat reservoir as well as the thermochemical reactor each comprise
a fluid inlet and a fluid outlet for the introduction and discharge
of the heat transfer fluid. In the case of this variant, the heat
transfer fluid circuit comprises a first adjustable valve device,
by means of which the fluid inlet of the thermochemical reactor can
be optionally connected to the fluid outlet of the first or second
heat reservoir. The heat transfer fluid circuit also comprises a
second adjustable valve device, by means of which the fluid outlet
of the thermochemical reactor can be optionally connected to the
fluid inlet of the first or second heat reservoir.
[0035] The invention furthermore relates a method for operating an
arrangement, preferably the one presented in the above, having a
heat transfer fluid circuit, in which at least one thermochemical
reactor, two heat reservoirs with different temperatures and a
temporary heat store are arranged and are fluidically connected to
one another by means of a heat transfer fluid circuit.
[0036] The temporary heat store used for carrying out the method
according to the invention comprises two thermally and fluidically
separate partial stores, in which a heat transfer fluid circulating
within the heat transfer fluid circuit can be accepted and
discharged in a way that is thermally and fluidically separated
from one another. In accordance with the method according to the
invention, in order to supply heat from the first heat reservoir
into the thermochemical reactor by means of the heat transfer
fluid, heat transfer fluid that is temporarily stored within the
first partial store of the temporary heat store is taken and
supplied to the first heat reservoir. At the same time, heat
transfer fluid is discharged from the thermochemical reactor and
introduced into the second partial store of the temporary heat
store.
[0037] In order to carry out a temperature change of the
thermochemical reactor from a high to a lower temperature level,
increasingly cooler heat transfer fluid temporarily stored in the
second partial store of the temporary heat store is taken and fed
to the heat sink. At the same time, initially cool however
increasingly warmer heat transfer fluid is discharged from the
thermochemical reactor and introduced into the first partial store
of the temporary heat store. In order to carry out a temperature
change of the thermochemical reactor from a low to a higher
temperature level, increasingly warmer heat transfer fluid
temporarily stored in the first partial store of the temporary heat
store is taken and fed to the heat source. At the same time,
initially cool however increasingly warmer heat transfer fluid is
discharged from the thermochemical reactor and introduced into the
second partial store of the temporary heat store in a thermally
stratified manner.
[0038] In a preferred embodiment of the method, at least two
thermochemical reactors are available, which each comprise a
separate housing as well as a fluid inlet and a fluid outlet. In
the case of this variant, the at least two thermochemical reactors
are fluidically connected to each other in parallel.
[0039] Thereby, the valve system comprises a first adjustable valve
device for each available thermochemical reactor, by means of which
the fluid inlet of the respective thermochemical reactor can be
optionally connected to the first or the second heat reservoir. The
valve system comprises a second adjustable valve device for each
available thermochemical reactor, by means of which the fluid
outlet of the respective thermochemical reactor can be optionally
connected to the first or the second heat reservoir. The switching
of the first existing valve devices to connect the thermochemical
reactors to the first or the second heat reservoir takes place in a
time-delayed manner. The switching of the available second valve
devices to connect the thermochemical reactors to the first or the
second heat reservoir also takes place in a time-delayed manner.
The time-delayed switching of the individual thermochemical
reactors makes a time-delayed regeneration of sensitive heat
possible in connection with the temporary heat store, thereby
resulting particularly low loss during the temperature change.
[0040] Other important features and advantages of the invention
result from the subclaims, the drawings and the related figure
description based on the drawing.
[0041] It is to be understood that the features explained in the
aforementioned and following cannot only be used in the
respectively indicated combination, but also in other combinations
or alone, without departing from the scope of the present
invention.
[0042] Preferred exemplary embodiments of the invention are
represented in the drawings and will be described in more detail in
the following description, wherein the same reference numbers will
refer to the same or similar or functionally identical
components.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] On a schematic level respectively, the figures show
[0044] FIG. 1 to 4 arrangement according to the invention in
various operating states,
[0045] FIG. 5 the construction of a temporary heat store according
to the invention of the arrangement in FIGS. 1 to 4 in a detailed
view,
[0046] FIG. 6 a first variation of the temporary heat store in FIG.
5,
[0047] FIG. 7 a second variation of the temporary heat store in
FIG. 5,
[0048] FIG. 8-11 a variant of the arrangement of FIGS. 1 to 4 with
a plurality of thermochemical reactors, which can be switched to
one another in a time-delayed manner.
DETAILED DESCRIPTION
[0049] FIG. 1 shows an example of an arrangement 1 according to the
invention, in particular, of a refrigerating machine or of a heat
pump. The arrangement 1 comprises a first heat reservoir 2a with a
first temperature T.sub.1 and a second heat reservoir 2b with a
second temperature T.sub.2. Furthermore, the arrangement 1
comprises a thermochemical reactor 5, which is or can be thermally
and fluidically connected to both heat reservoirs 2a, 2b. For this
purpose, the arrangement 1 comprises a heat transfer fluid circuit
3, in which a heat transfer fluid F is arranged to transport heat
between the two heat reservoirs 2a, 2b and the thermochemical
reactor 5.
[0050] Under "thermochemical reactor", in the present document, an
apparatus is understood, in which conversion processes are
instigated by supplying and dissipating heat at different
temperatures T.sub.1, T.sub.2--also known by the person skilled in
the art as reaction heat, sorption heat, or phase change heat. The
thermochemical reactor 5 can comprise a reservoir 15, which is only
schematically shown in the figures, in which thermochemical
reactions take place, with a heat transfer structure for the supply
and dissipation of the reaction heat. The first temperature T.sub.1
comprises a greater value than the second temperature T.sub.2,
meaning the first heat reservoir 2a acts as a heat source, from
which heat can be transferred to the thermochemical reactor 5 by
means of the heat transfer fluid F. In contrast, the second heat
reservoir 2b acts as a heat sink, at which heat can be transferred
from the thermochemical reactor 5 by means of the heat transfer
fluid F.
[0051] Furthermore, a temporary heat store 100 is available in the
heat transfer fluid circuit 3 for temporarily storing the heat
transfer fluid F. The temporary heat store 100 makes a temperature
change of the thermochemical reactor 5 possible with very little
energy loss from temperature T.sub.1 to temperature T.sub.2 and
vice versa.
[0052] The construction of the temporary heat store 100 is shown in
a schematic detailed illustration in FIG. 5. In accordance with
FIG. 4, the temporary heat store 100 has a first partial store 101a
with a variable storage volume 102a and has a second partial store
101b with a variable storage volume 102a that is thermally and
fluidically separated from this. The volume-variable first partial
store 101a of the temporary heat store 100 is designed to be
complementary to the volume-variable second partial store 101b so
that the overall volume formed by the two partial stores 101a, 101b
is always constant.
[0053] The temporary heat store 100 can also be referred to as a
sensitive short-term heat store, regenerator or temperature changer
and represents a component of the arrangement 1 according to the
invention, which initially makes a temperature change in the
thermochemical reactor 5 with low levels of energy losses at all
possible.
[0054] The temporary heat store 100 is designed to simultaneously
hold and output a first and a second fluid mass of the heat
transfer fluid F with variously stratified temperature profiles.
The temporary heat store 100 is designed to simultaneously hold and
output a first and a second fluid mass of the heat transfer fluid
F, wherein both fluid masses have different temperature
stratifications, which are qualitatively characterized with
different grey shades. The darker the grey shade, the higher the
present local temperature level is.
[0055] FIG. 6 shows a further embodiment of the reservoir 103 in
FIG. 5. In the case of the reservoir 103 in FIG. 2, a coil-like
structure 113 is arranged in the interior space 107 of the housing
104. The coil-like structure 113 gives the interior space 107 the
geometry of a fluid channel 114 with a coil-like geometry. The
fluid channel 114 is thereby delimited by the coil-like structure
113 and by the housing 104, in particular, by its circumferential
wall 111. The coil-like structure 103 can be designed as an insert
115 arranged in the interior space. The coil-like structure 113 can
comprise at least ten windings 116, preferably even at least 20
windings. The separation element 106 is designed to be adjustable
along the coil-like fluid channel 114. That means that the
geometrical shape of the separation element 106 is selected in such
a way that, within the interior space 107, it is adjustable along
the fluid channel 114, which is delimited by the circumferential
wall 111 and the coil-like structure 113.
[0056] FIG. 7 shows another variant of the example of FIG. 5, where
the reservoir 103 is designed as a hose-like body 117, which at
least portionally extends along an extension direction E in a
non-linear manner. In the case of this variant, the separation
element 106 abuts the inner side 112 of a circumferential wall 111
of the pipe-shaped body 117 to form the two volume-variable partial
stores 101a, 101b along the extension direction E in a moveable
manner. This variant makes a particularly spatially compact
arrangement of the reservoir 103. Preferably, a length of the
housing 104 or of the hose-like body 117 measured along the
extension direction E is at least ten times, preferably at least
twenty times a transverse direction Q measured transversely to the
extension direction E.
[0057] As is evident in FIG. 1, the first partial store 101a of the
temporary heat store 100 is fluidically connected to the first heat
reservoir 2a. In contrast, the second partial store 101b of the
temporary heat store 100 is fluidically connected to the second
heat reservoir 2b.
[0058] The functional principle of the temporary heat store 100 is
based on a thermally insulated fluid reservoir with end-side
openings and a large length/cross-sectional ratio, within which an
insulating displaceable separating body is arranged, as is
schematically shown in FIG. 5.
[0059] In the example scenario in FIG. 5, the temporary heat store
100 is designed as a reservoir 103. This reservoir 103 comprises a
housing 104. The housing 104 delimits an interior space 107, in
which a separation element 106 is moveably arranged, which
thermally and fluidically insulates both partial stores 101a, 101b
from each other. The separation element 106 divides the interior
space 107 into a volume-variable first partial store 101a and a
second partial store 101b, which is also volume-variable and is
thermally and fluidically insulated from the first partial store
101a. Preferably, the separation element 106 of the temporary heat
store 100 is arranged in such a way that it can be displaceably
moved easily in the longitudinal and extension direction in a
fluid-tight manner to the greatest extent possible due to pressure
differences between the two partial stores.
[0060] As can be recognized in the figures, the thermochemical
reactor 5 and the temporary heat store 100 each have separate
reservoirs 15 and 103.
[0061] As can be recognized in FIG. 5, a first through-opening 108a
is available in the housing 104 for introducing and discharging the
heat transfer fluid F at temperature T.sub.1 into the first partial
store 101a or out of the first partial store 101a. Furthermore, a
second through-opening 108b is available in the housing 104 for
introducing and discharging the heat transfer fluid F with the
temperature T.sub.2 into the second partial store 101b or out of
the second partial store 101b.
[0062] The housing 104 is designed as a pipe body 105, which
extends in a straight line along an axial direction A. The
separation element 106 abuts the inner side 112 of a
circumferential wall 111 of the pipe body 105 to form the two
volume-variable partial stores 101a, 101b along the axial direction
A in a moveable manner. The first through-opening 108a is arranged
on a first longitudinal end 109a. The second through-opening 108b
is arranged on a second longitudinal end 109b situated opposite to
the first longitudinal end 109a.
[0063] As FIG. 3 illustrates, in the case of a separation element
106 arranged at the far left, meaning on the first through-opening
108a, the temporary heat store 100 can be filled with a
temperature-stratified fluid column of the heat transfer fluid F,
wherein the temperature level at the separation element
approximately corresponds to temperature T.sub.2 and the
temperature level at the outlet 108b almost reaches temperature
T.sub.1. In accordance with FIG. 4, the separation element 106 can
be pushed to the right, towards the second through-opening 108b by
a heat transfer fluid F flowing from the left via the first
through-opening 108a, which is initially hot, but thereby
increasingly becomes cooler, whereby the temporary heat store 100
is filled with a temperature-stratified fluid column of the heat
transfer fluid F, wherein the temperature level at the separate
element approximately corresponds to temperature T.sub.1 and the
temperature level at the outlet 108b almost reaches temperature
T.sub.2. At the same time, the liquid column stratified from
temperature T.sub.1 to temperature T.sub.2 is pressed to the right
through the second through-opening 108b until the separation
element 106 is located on the second through-opening 108b and the
temperature-stratified liquid column of the heat transfer fluid F
has completely been replaced.
[0064] The temperature profiles of the liquid columns of the heat
transfer fluid F stored in the partial store of the temporary heat
store causes that, in the case of pressing the
temperature-stratified liquid column out of the second partial
store, initially warm and then, however, increasingly cooler heat
transfer fluid is pressed out. Thereby, this partial store can be
used for the gradual cooling of a thermochemical reactor 5.
[0065] Complementary to this, in the case of pressing the
temperature-stratified liquid column out of the first partial
store, initially cool and then, however, increasingly warmer heat
transfer fluid is pressed out. Thereby, this partial store can be
used for the gradual heating of a thermochemical reactor 5.
[0066] According to FIG. 5, a first sensor element 110a is provided
on the first through-opening of the temporary heat store, by means
of which it can be determined whether the separation element 106 is
located in a first end position, in which it has a minimum distance
away from the first through-opening 108a. In an analogous manner, a
second sensor element 110b can be provided on the second
through-opening 108b, by means of which it can be determined
whether the separation element 106 is located in a second end
position, in which the it has a minimum distance away from the
second through-opening 108b.
[0067] When now viewing FIG. 1 again, it can be recognized that a
conveying device 8 to drive the h F is provided in the heat
transfer fluid circuit 3.
[0068] In the heat transfer fluid circuit 3, furthermore, a valve
system 9 is available, which comprises a first adjustable valve
device 10a and a second adjustable valve device 10b. By means of
the two valve devices 10a, 10b, the heat transport between the two
heat reservoirs 2a, 2b, the thermochemical reactor 5 and the
temporary heat store 100 can be set and controlled as a result. In
order to control the valve devices 10a, 10b of the valve system 9,
a regulation/control device 4 is provided, which interacts which
works together with the valve devices 10a, 10b.
[0069] The first and the second heat reservoir 2a, 2b as well as
the thermochemical reactor 5 each comprise a fluid inlet 11a, 11b,
11c and a fluid outlet 12a, 12b, 12c for introducing and
discharging the heat transfer fluid.
[0070] By means of the first adjustable valve device 10a, the fluid
inlet 11b of the thermochemical reactor 5 can be optionally
connected to the fluid outlet 12a, 12c of the first or the second
heat reservoir 2a, 2b. By means of the second adjustable valve
device 10b, the fluid outlet 12b of the thermochemical reactor 5
can be optionally connected to the fluid inlet 11a, 11c of the
first or the second heat reservoir 2a, 2b.
[0071] As can be recognized in FIG. 1, the temporary heat store 100
is fluidically connected in parallel to the second valve device 10b
in such a way that the fluid inlet 11a of the first heat reservoir
2a fluidically communicates with the first partial store 101a and
the fluid inlet 11c of the second heat reservoir 2b fluidically
communicates with the second partial store. The first valve device
10a and the second valve device 10b are each designed as 3/2-way
switching valve 13a, 13b.
[0072] In the following, now, a full thermal cycle of the
thermochemical reactor 5 is explained where the thermochemical
reactor 5 is switched between a first state at temperature T.sub.1
of the first heat reservoir 2a and a second state at temperature
T.sub.2 of the second heat reservoir 2b.
[0073] Both valve devices 10a, 10b of the valve system 9 can be set
into an operating state shown in FIG. 1 by the regulation/control
device 4. In this operating state, the first partial store 101a has
a maximum volume and the second partial store 101b has a minimum
volume, meaning the first partial store 101a of the temporary heat
store 100 is filled with heat transfer fluid F, which comprises a
temperature stratification increasing from left to right up to
almost temperature T.sub.1. On the contrary, the second partial
store 101b is empty. In this operating state, the heat transfer
fluid circuit 3 forms a first partial circuit 14a, in which the
heat transfer fluid F circulates between the thermochemical reactor
5 and the second heat reservoir 2b. In this operating state, the
heat transfer fluid F transfers heat from the thermochemical
reactor 5 into the second heat reservoir 2b, meaning reaction heat
is dissipated out of the thermochemical reactor 5 near temperature
level T.sub.2.
[0074] During the course of the thermal cycling, the thermochemical
reactor 5 is now switched into a state at temperature T.sub.1 of
the first heat reservoir 2a, whereby, initially, a temperature
change is carried out in order to essentially heat the thermal
masses of the reactor 5. In addition, both valve devices 10a, 10b
are initially set into an operating state shown in FIG. 2 by the
regulation/control device 4. In the operating state shown in FIG.
2, both valve devices 10a, 10b are configured in such a way that
the heat transfer fluid F is transported from the first partial
store 101a of the temporary heat store 100 into the first heat
reservoir 2a. Furthermore, heat transfer fluid F is transported
from the first heat reservoir 2a into the thermochemical reactor 5.
Furthermore, heat transfer fluid F is transported from the
thermochemical reactor 5 into the second partial store 101b.
[0075] In this operating state, the temperature-stratified heat
transfer fluid F of the first partial store 101a of the temporary
heat store 100 is pressed into the heat reservoir 2a, whereby the
thermal reactor is consequently heated up to its temperature level
T.sub.1. In turn, the second partial store 101b of the temporary
heat store 100 is filled with a cool and increasingly warmer heat
transfer fluid F coming from the thermochemical reactor 5.
[0076] As soon as the heat transfer fluid F temporarily stored in
the first partial store 101a of the temporary heat store 100 has
completely been taken from the temporary heat store 100, the
separation element 106 is in the aforementioned first end position,
which can be detected by the regulation/control device 4 by means
of the first sensor element 110a.
[0077] Being triggered by the first sensor element 110a, both valve
devices 10a, 10b are initially set into an operating state that is
schematically shown in FIG. 3 by the regulation/control device
4.
[0078] In the operating state schematically shown in FIG. 3, the
heat transfer fluid circuit 3 forms a second partial circuit 14b,
in which the heat transfer fluid F circulates between the
thermochemical reactor 5 and the first heat reservoir 2a. In this
way, the heat transfer fluid F is transported from the first heat
reservoir 2a to the thermochemical reactor. In this operating
state, reaction heat is transferred from the first heat reservoir
into the thermochemical reactor 5 at temperature level T.sub.1. In
this operating state, the first second partial store 101b has a
maximum volume and the first partial store 101a has a minimum
volume, meaning the second partial store 101b of the temporary heat
store 100 is filled with heat transfer fluid F, which comprises a
temperature stratification increasing from left to right up to
almost temperature T.sub.1. In contrast, the first partial store
101b is empty. The operating state shown in FIG. 3 can be referred
to as "heat-supply mode".
[0079] In order to instigate a "cooling mode", subsequently, both
valve devices 10a, 10b can be set into an operating state shown in
FIG. 4 by the regulation/control device 4. In the operating state
shown in FIG. 4, both valve devices 10a, 10b are configured in such
a way that the heat is transported from the second partial store
101b into the second heat reservoir 2b by means of the heat
transfer fluid F. At the same time, by pressing out hot heat
transfer fluid, sensitive heat is transported from the
thermochemical reactor 5 into the first partial store 101a of the
temporary heat store 100.
[0080] As soon as the heat transfer fluid F temporarily stored in
the second partial store 101b of the temporary heat store 100 has
completely been taken from the temporary heat store 100, the
separation element 106 is in the aforementioned second end
position, which can be detected by the regulation/control device 4
by means of the second sensor element 110b. In this state, the
first partial store 101a is completely filled with the heat
transfer fluid F (cf. FIG. 1) Being triggered by the sensor element
110b, the two valve devices 10a, 10b is switched into the operating
state shown in FIG. 1 again by the regulation/control device 4 and
a complete switching cycle of the thermochemical reactor 5 is
completed.
[0081] FIG. 8 shows a further embodiment of the arrangement of the
FIGS. 1 to 4 where the arrangement 1 not only has a single
thermochemical reactor, but three such thermochemical reactors 5a,
5b, 5c. Each thermochemical reactor 5a, 5b, 5c has its own housing
20a and a respective fluid inlet 11b as well as a fluid outlet 12b.
As can be recognized in FIG. 8, the three thermochemical reactors
5a, 5b, 5c are fluidically connected to each other in parallel. In
the present example, the reactors can be considered sorption
reactors, which desorb a working material at a high temperature
T.sub.1 and adsorb a working material at a lower temperature
T.sub.2. They receive the desorption heat required for this from a
high-temperature heat reservoir 2a serving as a heat source and
emit adsorption heat to a low-temperature heat reservoir 2b acting
as a heat sink in a time-delayed manner.
[0082] The valve system (9) comprises a first adjustable valve
device 10a for each of the three thermochemical reactors 5a, 5b,
5c, by means of which the fluid inlet 11b of the respective
thermochemical reactor 5a, 5b, 5c can be optionally connected to
the first or the second heat reservoir 2a, 2b of the temperature
T.sub.1 or T.sub.2. The valve system 9 furthermore comprises a
second adjustable valve device 10b for each of the three
thermochemical reactors 5, by means of which the fluid outlet 12b
of the respective thermochemical reactor 5a, 5b, 5c can be
optionally connected to the first or the second heat reservoir 2a,
2b. The temporary heat store 100 is installed in the arrangement 1
in such a way that the first partial store 101a fluidically
communicates with the first heat reservoir 2a and the second
partial store 101b fluidically communicates with the second heat
reservoir 2b.
[0083] In the example in FIGS. 8 to 11, the three thermochemical
reactors 5a, 5b, 5c are cycled analogously to the example in FIGS.
1 to 4, however, in a time-delayed manner to one another.
[0084] In FIG. 8, a stationary switching state of the first and
second valve devices 10a, 10b is shown where the sorption reactor
5a at temperature T.sub.1 is desorbed by a heat supply from the
first heat reservoir 2a while the second and the third sorption
reactor 5b, 5c are in the adsorption process due to the heat
dissipation to the second heat reservoir 2b at temperature T.sub.2.
The first partial store 101a of the temporary heat store 100 is
thereby filled with heat transfer fluid F at temperature T.sub.1,
whereas the second partial store 101 is empty.
[0085] The subsequent switching position of the first and the
second valve devices is shown in FIG. 9 where the second sorption
reactor 5b is heated by means of the fact that the first valve
device 10a associated with the second sorption reactor 5b is
switched. As a result, the fluid inlet 11b of the second sorption
reactor 5b is connected to the first heat reservoir 2a just like
the first sorption reactor 5a. The third sorption reactor 5c remain
connected to the second heat reservoir 2b on the inlet side. By
means of this, the second sorption reactor 5b is heated and the
cool heat transfer fluid, which is stratified ranging from being
cool up to temperature T.sub.2, is pushed into the second partial
store 101b of the temporary heat store 100. The heat transfer fluid
stored in the first partial store 101a of the temporary heat store
100 stratified up to temperature T.sub.1 is pushed into the first
heat reservoir 2a.
[0086] This unsteady temperature change process in the temporary
heat store 100 has ended as soon as the heat transfer fluid F
stratified up to temperature T.sub.1 in the temporary heat store
100 has been completely replaced by cooler heat transfer fluid
stratified up to temperature T.sub.2 in the temporary heat store
100. Then, the second partial store 101b is completely filled and
the first partial store 101a is empty. The illustration of FIG. 10
shows this scenario. Thereby, the sorption reactors 5a and 5b are
in desorption mode and reactor 5c is in adsorption mode.
[0087] The next switching position of the first and the second
valve devices 10a, 10b in accordance with FIG. 11 is used to cool
the first sorption reactor 5a. For this, the first sorption reactor
5a is fluidically connected to the second heat reservoir 2b. In
analogy to the heating process, the first sorption reactor 5a is
cooled and, thereby the contained heat transfer fluid, which is
initially hot at T.sub.1 is pressed into the first partial store
101a of the temporary heat store 100. At the same time, the heat
transfer fluid F stored in the temporary heat store 100 is pressed
out of the second partial store 101b of the temporary heat store
100. This subprocess also ends by switching the second valve device
10b associated with the first thermochemical store 5a as soon as
the first partial store is completely filled with the heat transfer
fluid F stratified up to temperature T.sub.1 and the second partial
store 101b has been completely emptied.
[0088] This state corresponds to the state according to FIG. 8 with
the difference that, now, the second sorption reactor 5b is in
stand-alone stationary desorption mode. The partial cycles
described in the above have also functioned to further activate the
entire cycle around a sorption reactor. In order to complete a full
cycle, 3*4=12 partial cycles are required until the initial state
according to FIG. 8 is reached.
[0089] In the preceding explained example, the time-delayed
switching of the first and the second valve devices 10a 10b take
place in such a way that, at the same time, at least one of the
sorption reactors 5a, 5b, 5c and a maximum of two of the available
reactors 5a, 5b, 5c have the temperature level T.sub.1 of the first
heat reservoir 2a. Thereby, it is possible to optimized the time
allotments for the desorption and adsorption of each sorption
reactor independent of the number of sorption reactors used.
[0090] Even in the case of the variant of the arrangement according
to the invention with three thermochemical reactors described in
the above based on FIGS. 8 to 11--in other variants, another number
of thermochemical reactors can be selected--with the aid of the
temporary heat store 100, the sensitive heat of the heat transfer
fluid F contained in a thermochemical reactor to be thermally
cycled can be recovered at high percentages. Depending on the
volume design, this also applied to a part of the sensitive heat of
stationary heat storage masses all the way to percentages of latent
amounts of heat implemented therein, for example, sorption heat in
the present case.
* * * * *