DE202023104488U1 - device for generating heat - Google Patents

Abstract

Device for generating heat for feeding it into a heating circuit (12), comprising
- a high-pressure pump (2) connected to a liquid circuit and driven by a motor, in particular an electric motor, with an inlet (4) through which the liquid to be pumped enters the pump (2) and with an outlet (5) from which the pumped liquid exits,
- at least one heat generator (6) connected to the liquid circuit, downstream of the pump (2) and causing friction in the liquid flow by reducing the flow cross-section, wherein the heat carrier (6) has a cross-sectional geometry that cannot be influenced by the delivery pressure of the liquid flow, so that the temperature of the liquid flow conveyed by the at least one heat generator (6) is increased,
- a liquid reservoir (10) connected to the liquid circuit and connected downstream of the at least one heat generator (6) in the flow direction of the liquid, and
- a heating circuit (12) connected to the liquid storage tank (10).

Description

The invention relates to a device for generating heat for feeding it into a heating circuit.

Examples of such devices are heat pumps. According to the heat pump principle, heat is extracted from a heat source, for example the ambient air (outside air) or another heat source, such as the soil or groundwater, and fed to an evaporator. The evaporator is part of a fluid circuit in which the heat extracted from the heat source evaporates the liquid in the circuit. This is typically a coolant. This gaseous phase is compressed in a compressor, which increases the temperature level of the gaseous fluid. In a second heat exchanger, this gas is liquefied by condensation, which releases heat. This heat exchanger is connected to a heating circuit through which the heat gained is distributed throughout a building. The liquefied coolant is then fed to the evaporator via a throttle. Heat pumps are highly efficient for the purposes of heating buildings. However, the flow temperature that can be generated with a heat pump for a heating circuit is lower than the flow temperature of conventional oil or gas-fired heating systems, which do not operate panel radiators such as underfloor heating. If existing properties are to be heated with heat pumps, this often requires not only extensive renovation work, but also a change to the existing heating system. In any case, the heat radiation surfaces must be significantly enlarged due to the lower flow temperature. It may be necessary to install underfloor heating at a later date. The cost, especially in terms of money, is considerable.

Out of WO 2010/057491 A2 A device for mechanically heating a liquid is known. This comprises a container with a container wall that is closed on the periphery and contains the liquid to be heated. One or more elements with openings and/or capillaries and/or pores are arranged in the container, through which the liquid flows and is heated by the friction that occurs. For this purpose, one or more elements are set in rotation so that the liquid is pushed through the elements, which are designed like wings. Heat can be generated using this principle, but not to a sufficient extent to be able to use the heat generated effectively to feed it into a heating circuit.

US 3,813,036 discloses a heating system. This known heating system comprises a closed oil circuit. A pump pumps oil through a friction heating element, so that the temperature at the outlet of this friction heating element is higher than at the inlet. According to this known heating system, several such heating elements can also be arranged parallel to one another. One or more heat radiation units are connected downstream of the friction heating element(s) as heat generators. The heat generated is emitted via these. The outlet of the heat radiation unit(s) is connected to a collecting container. The friction heating elements are woven metal wire that is compressed and arranged in a cylinder block. A disadvantage of this known heating system is that the pump must be operated for the entire heating period. Another disadvantage is that the cross-sectional area of the heat generator that can be flowed through changes depending on the pressure applied, as it is made of woven wire. The maximum operating pressure is specified as 137 bar. This heating system is a standalone system that cannot be combined with an existing heating system.

Against the background of the state of the art described above, it would therefore be desirable to have a device, in particular an electrically operated device, for generating heat for the purpose of feeding it into a heating circuit, with which flow temperatures can also be generated which correspond to those of an otherwise conventional oil or gas heating system with which radiators as heat-emitting elements are supplied with heat.

The object of the invention is therefore to propose such a device.

• - eine in einen Flüssigkeitskreislauf eingeschaltete, motorisch insbesondere elektromotorisch angetriebene Hochdruckpumpe mit einem Zulauf, über den die zu fördernde Flüssigkeit in die Pumpe eintritt, und mit einem Auslauf, aus dem die geförderte Flüssigkeit austritt,
• - zumindest einen in den Flüssigkeitskreislauf eingeschalteten, der Pumpe nachgeschalteten, in dem Flüssigkeitsstrom durch eine Reduzierung des Strömungsquerschnittes Reibung verursachenden Wärmeerzeuger, wobei der Wärmeerzeuger eine durch den Förderdruck des Flüssigkeitsstroms nicht beeinflussbare Querschnittsgeometrie aufweist, sodass die Temperatur des durch den zumindest einen Wärmeerzeuger geförderten Flüssigkeitsstroms erhöht wird,
• - einen in den Flüssigkeitskreislauf eingeschalteten und dem zumindest einen Wärmeerzeuger in Strömungsrichtung der Flüssigkeit nachgeschalteten Flüssigkeitsspeicher sowie
• - einen an den Flüssigkeitsspeicher angeschlossenen Heizkreis.

This object is achieved by a device for generating heat for feeding it into a heating circuit, comprising

• - a high-pressure pump connected to a liquid circuit and driven by a motor, in particular an electric motor, with an inlet through which the liquid to be pumped enters the pump and with an outlet from which the pumped liquid exits,
• - at least one heat generator connected to the liquid circuit, downstream of the pump, causing friction in the liquid flow by reducing the flow cross-section, wherein the heat heat generator has a cross-sectional geometry that cannot be influenced by the delivery pressure of the liquid flow, so that the temperature of the liquid flow conveyed by the at least one heat generator is increased,
• - a liquid storage device connected to the liquid circuit and connected downstream of at least one heat generator in the flow direction of the liquid, and
• - a heating circuit connected to the liquid storage tank.

This heat generating device comprises a high-pressure pump, preferably driven by an electric motor. This pump is connected to a liquid circuit. The liquid flow emerging from the outlet of the pump acts on at least one heat generator connected downstream of the pump. The liquid flow is conveyed through the heat generator. For the desired heat generation, the heat generator reduces the cross-sectional area through which the flow can occur, thus providing a corresponding counterpressure. The heat generator is designed in the manner of a hydraulic orifice with one or more openings. The sum of these openings then represents the free cross-sectional area through which the flow can occur. The heat generator thus introduces heat into the liquid flow conveyed by the at least one heat generator via the friction generated in the liquid flow conveyed by the at least one heat generator, so that the temperature of the liquid flow conveyed by the pump through the heat generator is higher at the outlet of the same than at its inlet. The heat generator counteracts the liquid flow conveyed by the high-pressure pump with a counterpressure. The higher the back pressure from the heat generator, the greater the temperature lift that can be coupled into the liquid flow. A temperature lift that is sufficient for many cases can be generated with back pressures of more than 120 to 150 bar. High-pressure pumps that can overcome a back pressure of 200 bar or more are preferred. The back pressure provided by the heat generator will be designed to be correspondingly high. It is possible to design the heat generator so that it contains several such hydraulic orifices connected in series in the direction of flow of the liquid, as well as a design in which several individual heat generators are connected in series. These can certainly be heat generators of different types.

Between one or the last heat generator in the direction of flow and the liquid storage tank there is a relaxation section in which the pumped liquid relaxes so that it does not flow into the liquid storage tank with excessive pressure. The liquid storage tank is preferably thermally insulated so that the heat introduced into the liquid by the heat generator(s) can be stored in it. Such a liquid storage tank can be, for example, the hot water tank (boiler) that is already present in a conventional oil or gas heating system. The heating circuit, which is fed by the liquid heated in the liquid storage tank, is connected to this. The heating circuit can be connected to the liquid storage tank independently of a heat generation circuit pumped by the pump. A circulation pump connected to this heating circuit ensures the necessary liquid transport to the individual heat release points. A design is possible in which the return of the heating circuit is connected directly to the inlet of the pump. In this case, the heating circuit can also be operated in series with the heat generation.

In order to heat the contents of such a liquid reservoir to the intended flow temperature again after a corresponding drop in temperature without having to pump the liquid through the entire heating circuit, it is advantageous to provide a line that bridges the heating circuit and connects the liquid reservoir directly to the pump inlet. A heat generation circuit is then provided via this heating circuit bypass line. When the pump is in operation, the contents of the liquid reservoir can then be heated to the desired temperature by circulating it. The liquid reservoir is typically equipped with a temperature sensor to monitor the liquid temperature prevailing in it. Studies have shown that with such a heat generation device with a heat generator that provides a back pressure of around 200 bar, 30 l of water can be heated by 10°C in one minute. In a correspondingly short time, a liquid container of 80 l, which corresponds to the usual size of a conventional boiler, is then heated back to the desired temperature.

In a further development of such a heat generating device, it is intended to use not only the introduced temperature, but also the kinetic energy coupled into the liquid when it is heated. The kinetic energy coupled into the liquid jet for the heat generation, which the liquid conveyed by the at least one heat generator has, is not required for heating the liquid in the liquid reservoir. Therefore, in various In various embodiments, this kinetic energy is used and an aggregate is connected to the flow path between the heat generator and the liquid reservoir, which aggregate is driven by the liquid jet (liquid flow) emerging from the heat generator. Such an aggregate can be one that provides no or only a small counterpressure. According to another embodiment of such a heat generating device, it is provided that the aggregate driven by the liquid flow itself generates a not inconsiderable counterpressure. This is typically lower than the counterpressure caused by the heat generator(s). In the first case, it can be, for example, a blade turbine arranged in a housing. In the second case, the aggregate can be designed as an axial piston pump, for example. Both measures can be used to make the kinetic energy present in the liquid flow usable, for example to drive a generator and thus recover energy, thereby improving the energy balance of the heat generating device.

In another such embodiment, the output of the heat generator is provided for the input of a hydraulic motor, the output of which is connected to the liquid reservoir. The hydraulic motor driven by the high-pressure pump can be used to support the drive of the high-pressure pump by means of the electric motor. This also improves the energy balance of the heat generating device, since the hydraulic motor supports the torque of the electric motor and thus less electrical energy is required to operate the heat generating device.

If a significant counterpressure is also provided by such a unit downstream of the heat generator, as is the case with an axial piston pump, for example, this also contributes to an increase in the temperature of the liquid flowing through it due to the friction acting on the liquid. In this respect, such a design of the heat generation device can also be referred to as a first heat generator and a second heat generator downstream of this.

If a unit generating back pressure is connected downstream of a heat generator, such as an axial piston engine, according to a preferred embodiment, the reduction in flow cross-section through the heat generator is kept constant at least as far as possible up to the inlet of the downstream unit, thus no relaxation path, at least not a significant one, is provided between the heat generator and the unit generating a further back pressure.

In a preferred embodiment, it is provided that the heat generator is part of a heat exchanger. In such a design, the heat generator is located in a heat exchanger housing, with a fluid path being provided between the heat generator and the housing. The housing has a flow and a return connection and is connected to a heat exchanger circuit. In this way, the heat radiated via the jacket surface of the heat generator can be utilized. This additional heat generation can, as is the case in a preferred embodiment, also be used to heat the liquid in the liquid reservoir. A particularly effective measure for using the heat radiated by the heat generator is to use the heat generator heat exchanger as a heat source for a heat pump. In such a case, a coolant is used as the heat exchanger fluid, which flows into this heat generator heat exchanger in liquid phase via the return connection, evaporates due to the heat of the heat generator and exits the flow connection in gaseous form. A compressor connected to the supply line compresses the gaseous refrigerant. This is followed by a heat exchanger in which the heat supplied by the refrigerant is extracted and fed to the liquid storage tank. This heat exchanger is connected to the liquid storage tank via a corresponding liquid supply line and return line.

Appropriate valves are provided in the heat generation circuit to control or switch the device. The same applies to the heating circuit connected to the liquid storage tank.

Preferably, water is used as a liquid in such a heat generating device, especially if it is to be connected to an existing heating system. This can be easily heated to the desired or required flow temperature using the heat generating device described above. In an existing, particularly conventional heating system, the water boiler can serve as a liquid storage tank. Water as a liquid for operating the heat generating device is also advantageous because water can absorb less gravitational force than oil and thus the temperature yield is improved. The connection of the preferably electric motor-driven Pump and the heat generator(s) can be connected to an existing oil or gas heating system without any major effort. In this respect, the heat generation device described above is particularly suitable for retrofitting an existing oil or gas heating system. This means that an existing oil or gas heating system supplemented by the heat generation device can also be operated predominantly with green energy in hybrid operation. The advantages of such a heat generation device compared to retrofitting or installing heat pumps are the low acquisition costs and, above all, the implementation in existing heating systems, and therefore its cost-effectiveness.

• 1: Nach Art eines schematisierten Blockschaltbildes eine erfindungsgemäße Wärmeerzeugungseinrichtung,
• 2: Eine Wärmeerzeugungseinrichtung gemäß einer weiteren erfindungsgemäßen Ausgestaltung und
• 3: Eine Wärmeerzeugungseinrichtung gemäß noch einer weiteren erfindungsgemäßen Ausgestaltung.

The invention is described below using exemplary embodiments. They show:

• 1 : In the form of a schematic block diagram, a heat generating device according to the invention,
• 2 : A heat generating device according to a further embodiment of the invention and
• 3 : A heat generating device according to yet another embodiment of the invention.

The in 1 The heat generating device 1 shown comprises a high-pressure pump 2. The high-pressure pump 2 is driven by an electric motor 3, which has a power consumption so that it can be connected to the 220 V network.

The high-pressure pump 2 has an inlet 4. The liquid to be pumped enters this. The liquid pumped by the pump 2 is pumped out of the pump 2 through an outlet 5. A heat generator 6 is connected to the outlet 5. The heat generator 6 counteracts the liquid flow pumped by the pump 2 with a counterpressure. In the embodiment shown, this is approximately 200 bar. The high-pressure pump 2 is therefore designed so that the liquid flow pumped by it can overcome this counterpressure. This counterpressure of the heat generator 6 is provided by a hydraulic orifice with a single opening. This significantly reduces the cross-sectional area through which the flow can take place. This orifice induces turbulence and thus friction in the liquid flow pumped through it, which in turn results in an increase in the temperature of the liquid flow pumped by the heat generator. Thus, in the heat generating device 1, a liquid flow is heated by introducing kinetic energy and thus by friction.

In the embodiment shown, the heat generator 6 is followed by an axial piston pump 7 that drives a generator 8. Between the heat generator 6 and the inlet of the axial piston pump 7, the liquid flow conveyed by the heat generator 6 is not expanded, at least not significantly. The counterpressure provided by the axial piston pump 7 is lower than the counterpressure provided by the heat generator 6 to the liquid flow conveyed by the pump 2. The kinetic energy (motion energy) introduced into the liquid flow is used in this embodiment to drive the axial piston pump 7 and thus the generator 8. Since the axial piston motor 7 also opposes a counterpressure to the incoming liquid flow, the liquid flow also experiences friction in the axial piston motor 7, which contributes to a further increase in its temperature. In this respect, in this design of the heat generation device 1, the axial piston motor 7 can also be referred to as a heat generator.

The output of the axial piston pump 7 is connected to a liquid reservoir 10 via a line 9. In the embodiment shown, the line 9 serves as a relaxation line for relaxing the liquid flow conveyed therein. The liquid reservoir 10 is a heating boiler which is also connected to a burner (oil or gas burner) operated with fossil fuels in a manner not shown in detail. The content of the liquid reservoir 10 is, for example, 80 l.

In an embodiment not shown in the figures, the outlet of the heat generator 6 is directly connected to the liquid storage tank 10.

In a further development of the heat generating device 1 shown in the figure, a bypass line is inserted into the liquid path between the heat generator 6 and the liquid reservoir 10, via which the liquid flow can be introduced directly from the heat generator 6 into the liquid reservoir 10, bypassing the axial piston pump 7.

The liquid reservoir 10 is connected directly to the inlet 4 of the pump 2 via a bypass line 11. In this way, a heat generation circuit is provided, via which the liquid content in the liquid reservoir 10 can be heated by circulation.

The liquid reservoir 10 is connected to a heating circuit 12, the flow of which is indicated in the figure with the reference number 13 and the return of which is indicated in the figure with the reference number 14. are made. One or more circulation pumps are used to pump the liquid in the heating circuit 12. The heating systems already present in the building (typically radiators) are typically switched on in the heating circuit 12 to emit heat.

2 shows a heat generating device 1.1 which is basically constructed like the one to 1 described heat generating device 1. Therefore, the statements regarding the heat generating device 1 apply equally to the heat generating device 1.1. Identical components are identified with the same reference numerals, supplemented by a ".1" in the figure. The heat generating device 1.1 differs from the heat generating device 1 in that a hydraulic motor 15 is connected downstream of the heat generator 6.1 before the liquid heated by the heat generator 6.1 is fed to the liquid reservoir 10.1. The hydraulic motor 15 is located on the drive shaft of the electric motor 3.1 and thus supports the drive of the high-pressure pump 2.1. This means that the torque provided by the hydraulic motor 15 does not have to be provided by the electric motor 3.1 to drive the high-pressure pump 2.1, which is noticeable in a reduced power consumption of the electric motor 3.1.

3 shows another heat generating device 1.2. This corresponds to the heat generating device 1, which is why the relevant statements also apply equally to the heat generating device 1.2. Identical components are identified in the figure by the same reference numerals, supplemented by a ".2". The heat generating device 1.2 is ultimately a further development of the heat generating device 1. Likewise, any other heat generating device according to the invention could also be supplemented by the further development explained below. In the further development of the heat generating device 1 to form the heat generating device 1.2, the heat radiated by the heat generator 6.2 via its outer surface is used. The heat generator 6.2 is part of a heat exchanger, which is why this unit is also referred to below as the heat generator heat exchanger 16. The heat generator 6.2, which, like the other embodiments, is made up of three hydraulic orifices connected in series, for example, is located in a heat exchanger housing 17. The heat exchanger housing 17 has a return connection 18 and a flow connection 19. The fluid to be heated in the heat generator heat exchanger 16 is via the return connection 18 into the fluid path between the housing 17 and the outer surface of the heat generator 6.2 and exits heated from the flow connection 19 when the heat generating device 1.2 is in operation. The heat generator heat exchanger 16 is switched on in a heat exchanger circuit. In the 3 In the embodiment shown, the heat exchanger circuit is a heat pump circuit. A compressor 22 is connected to the flow line 20, which supplies a heat exchanger 21. The heat exchanger 21 is in turn connected to the return connection 18 of the heat generator heat exchanger 16 via a return line 23. The heat exchanger 21 itself has a condenser in the embodiment shown. A coolant that is usually used for these purposes serves as the heat exchanger fluid.

The heat exchanger 21 is connected to the liquid storage tank 10.2 via the flow line 20 and the return line 23. This means that the liquid in the liquid storage tank 10.2 is not only heated by the liquid jet heated by the heat generator 6.2, but also by the heat generated by the heat pump. The energy balance of the heat generating device 1.2 is therefore particularly favorable.

The invention has been described using exemplary embodiments. Without departing from the scope of protection described by the applicable claims, numerous further embodiments will become apparent to those skilled in the art to implement the inventive concept without these having to be explained in more detail in the context of these statements.

list of reference symbols

1, 1.2

heat generating device

2, 2.1

high-pressure pump

3, 3.1

electric motor

4

inflow

5

outlet

6, 6.1, 6.2

heat generator

7

axial piston pump

8

generator

9

bypass line

10, 10.1, 10.2

fluid storage

11

bypass line

12

heating circuit

13

lead time

14

return

15

hydraulic motor

16

heat generator heat exchanger

17

Housing

18

return connection

19

flow connection

20

supply line

21

heat exchanger

22

compressor

23

return line

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• WO 2010/057491 A2 [0003]
• US 3,813,036 [0004]

Claims (18)

Device for generating heat for the purpose of feeding it into a heating circuit (12), comprising - a high-pressure pump (2) which is connected to a liquid circuit and is driven by a motor, in particular an electric motor, and has an inlet (4) through which the liquid to be conveyed enters the pump (2) and an outlet (5) from which the conveyed liquid exits, - at least one heat generator (6) connected to the liquid circuit, downstream of the pump (2) and causing friction in the liquid flow by reducing the flow cross-section, wherein the heat carrier (6) has a cross-sectional geometry which cannot be influenced by the delivery pressure of the liquid flow, so that the temperature of the liquid flow conveyed by the at least one heat generator (6) is increased, - a liquid reservoir (10) connected to the liquid circuit and downstream of the at least one heat generator (6) in the flow direction of the liquid, and - a liquid reservoir (10) connected to the liquid reservoir (10). heating circuit (12). Facility according to claim 1 , characterized in that the heat generator (6) is designed in the manner of a hydraulic orifice with one or more flow openings. Facility according to claim 2 , characterized in that the heat generator (6), which is designed in the manner of a hydraulic orifice, has a single flow opening. Facility according to one of the Claims 1 until 3 , characterized in that the heat generator (6) is constructed from several hydraulic orifices connected in series. Facility according to one of the Claims 1 until 4 , characterized in that a relaxation section is provided between the last heat generator (6) in the flow direction of the liquid and the liquid reservoir (10). Facility according to one of the Claims 1 until 5 , characterized in that a component providing a counterpressure is connected downstream of a first heat generator (6). Facility according to claim 6 , characterized in that the component providing the counterpressure is an aggregate driven by the liquid jet emerging from the upstream heat generator (6). Facility according to claim 7 , characterized in that the component providing the counter pressure is a hydraulic axial piston motor (7). Facility according to claim 8 , characterized in that a generator (8) is driven by the axial piston motor (7). Facility according to claim 7 , characterized in that the component providing the counterpressure is a hydraulic motor (15) supporting the drive of the high-pressure pump (2.1). Facility according to one of the Claims 6 until 10 , characterized in that the counterpressure provided by the unit downstream of the heat generator (6) is lower than the counterpressure caused by the upstream heat generator (6). Facility according to one of the Claims 1 until 5 , characterized in that the liquid flow emerging from the at least one heat generator drives a rotatably drivable unit, in particular a generator, which does not provide any appreciable counterpressure. Facility according to one of the Claims 1 until 12 , characterized in that the heat generator (6.2) is located in a housing (17), wherein a fluid path is provided between the housing and the heat generator (6.2) in order to use heat radiated by the latter in the manner of a heat exchanger and the housing (17) is connected to a heat exchanger circuit. Facility according to claim 13 , characterized in that the heat generator (6.2) is connected to a heat exchanger circuit designed as a heat pump with a refrigerant as heat exchanger fluid. Facility according to claim 14 , characterized in that the housing (17) with the heat generator (6.2) located therein has an extension in the vertical direction, wherein the housing outlet from which the coolant evaporated by the heat of the heat generator (6.2) emerges is arranged in the upper end region of the housing (17) and the inlet of the liquid coolant is arranged in the lower end region of the housing (17). Facility according to one of the Claims 1 until 15 characterized in that the return (14) of the heating circuit (12) is connected to the inlet (4) of the pump (2). Facility according to one of the Claims 1 until 16 , characterized in that a bypass line (11) connecting the liquid reservoir (10) to the inlet (4) while bypassing the heating circuit (12) is connected to the inlet (4) of the pump (2). Facility according to one of the Claims 1 until 17 , characterized in that the liquid pumped by the high-pressure pump (2) is water or an aqueous solution.

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