FR2995668A1 - Heat pump installation for use in e.g. thermodynamic water-heater in dwelling house, has evaporator arranged upstream of container, where fluid is directed to evaporator for removing calories during circulation of fluid in circulation path - Google Patents

Abstract

The installation (200) has a heat pump whose evaporator (210) is arranged upstream of a heat buffering container (300). The container comprises a closed volume for placing a thermal storage fluid (312) and a circulation path (320) to ensure transfer of calories from a hot fluid towards the thermal storage fluid during circulation of the hot fluid in the circulation path and another circulation path (330). A fluid is intermittently directed to the evaporator of the heat pump for removing the calories from the container during circulation of the fluid in the latter circulation path. The thermal storage fluid is water or a phase shifting material. The hot fluid is air extracted from a building. The fluid is selected from a group consisting of outdoor air sucked by a heat pump, water coming from a buried geothermic sensor and/or water coming from a water table or a river.

Description

The present invention relates to the field of heat pumps generally abbreviated PAC. It applies in particular, although not exclusively to the field of thermodynamic water heaters generally called abbreviated CET. A thermodynamic water heater conventionally comprises a flask intended to store a volume of water heated by various means, including at least one heat pump, in addition to any more conventional means, such as, for example, an electrical resistance in the event of a necessary supplement. . An object of the present invention is to improve the known PAC installations. This object is achieved in the context of the present invention by means of a heat pump installation, characterized in that it comprises, upstream of the evaporator of the heat pump, a heat buffer tank comprising a volume closed, which houses a first thermal storage fluid, a first circulation path of a second hot fluid adapted to ensure a transfer of heat from the hot fluid to the storage fluid during the circulation of the second hot fluid in the first heating path. circulation and a second flow path of a third fluid to be intermittently directed to the evaporator of the heat pump to take heat from the heat buffer during the circulation of the third fluid in the second flow path. circulation. The present invention also relates to the aforementioned heat buffer as such. Other features, objects and advantages of the present invention will appear on reading the detailed description which follows, and with reference to the appended drawings given by way of nonlimiting examples and in which: FIG. 1 represents a view general schematic of a thermodynamic water heater installation according to the present invention, - Figure 2 shows a schematic perspective view of a first embodiment of a heat buffer according to the present invention, - Figure 3 Fig. 4 shows a perspective view of a heat buffer according to a second embodiment of the present invention, - Fig. 5 shows the variation of the heat buffer of Fig. 2. temperature of the first fluid contained in the heat buffer to provide thermal storage during charging and discharging phases as well as the temperature of the third the fluid directed towards the evaporator of the heat pump, and - Figures 6 and 7 show respective end views of two embodiments of heat buffer according to the present invention.

The invention will initially be described in the context of the general structure of the installation of the thermodynamic water heater 10 according to the present invention illustrated in the appended FIG. Essentially, this thermodynamic water heater 10 comprises a hot water tank 100, a heat pump 200 and a heat buffer tank 300 placed upstream of the evaporator 210 of the heat pump 200. hot water 100 may itself be subject to many embodiments known to those skilled in the art. It will not be described in detail later. Essentially, the hot water tank 100 comprises a thermally insulated tank 110 which has an inlet 112 connected to a water inlet and an outlet 114 connected to the hot water sampling point.

Mixing systems can be provided between the inlet 112 and the outlet 114 in a manner known per se. They will not be described in more detail later.

The water contained in the internal volume of the balloon 100 is heated by the heat pump 200 by heat transfer from the condenser 230 of the heat pump. The heat exchange between the condenser 230 and the internal volume of the balloon 100 can also be the subject of several variants. It can be achieved by a direct transfer by placing the condenser 230 within the balloon 100 or on the tank 110 (for example by arranging the condenser exchanger in contact with the tank 110 between the latter and the external thermal insulation of the tank. balloon), or through a heat exchanger between the condenser 230 and the sanitary water contained in the balloon 100, placed outside the balloon 100. Of course, the balloon 100 can be completed by a Another auxiliary source of calorie supply 150 shown in Figure 1. This auxiliary source may be an electrical resistance automatically supplied by a module depending on the actual temperature measurement of the water contained in the balloon 100 or controlled manually or any other source available, such as for example a source of solar energy type. The heat pump 200 is also of conventional construction per se. It comprises an evaporator 210, a compressor 220, a condenser 230 and an expander 240. A fluid preferably consisting of a refrigerant circulates in a closed circuit in the heat pump 200, between the evaporator 210, the compressor 220, the condenser 230 and the expander 240. At the evaporator 210, the refrigerant takes heat from a secondary fluid, in this case the third fluid flowing in the second path 330 of circulation of the heat buffer 300, and is thus vaporized. The compressor 220 most often powered by an electric motor raises the pressure and temperature of the gaseous refrigerant by compressing it.

At the level of the condenser 230, the refrigerant releases a portion of its calories to the balloon 100 and passes partially from the gaseous state to the liquid state. At the pressure reducer 240 or the pressure reducer, the pressure of the refrigerant is reduced. The structure and operation of such a heat pump 200 is known to those skilled in the art and will not be described in more detail later. As indicated above, the invention relates to the addition of a heat buffer 300 upstream of the evaporator 210. The heat buffer 300 comprises a reservoir 310 which defines a closed volume housing a first fluid of thermal storage 312. This first thermal storage fluid 312 may be water. It may be any other suitable material, such as, for example, a phase change material. The heat buffer 300 also defines a first flow path and a second flow path schematically shown as 320 and 330 in Fig. 1. The first flow path 320 is adapted for circulation of a second hot fluid between at least one inlet 322 and at least one outlet 324. The second circulation path 330 is designed for the circulation of a third fluid between at least one inlet 332 and at least one outlet 334 directed towards the evaporator 210. The first path The second circulation path 330 is also in thermal exchange relation with the first storage fluid 312. In option, the second circulation path 330 is in heat exchange relation with the first storage fluid 312. may also be in heat exchange relation with the first flow path 320. Preferably, the second hot fluid which flows in the first path Circulation 320 is stale air extracted from a building by standard mechanical ventilation. The air extracted from a building, for example a dwelling house, represents a constant source of energy, easily recoverable in a thermodynamic application and which can circulate permanently in the first circulation path 320 to ensure a transfer of calories from this hot fluid to the storage fluid 312 contained in the container 310 to thereby ensure accumulation and continuous storage in the container 310 of the available calories at the second hot fluid. The third fluid flowing in the second flow path 330 is the fluid directed to the evaporator 210 for transferring calories to the refrigerant of the heat pump. In the context of the invention, before going through the evaporator 210, this third fluid passes through the heat buffer 300 to take the calories stored in the static storage fluid 312, from the second hot fluid. The third fluid is preferably air driven by a fan or equivalent 350 schematically shown in Figure 1. It can also be water from a buried geothermal sensor (for a geothermal heat pump), a water table phreatic or river. In these cases, the flow is driven by a pump. Such a fan or equivalent 350 is shown upstream of the heat buffer 300 in FIG. 1. It may, however, be positioned between the heat buffer 300 and the evaporator 210 or downstream of the evaporator 210. The heat buffer 300 itself can be subject to many variants. It can be installed horizontally as well as vertically.

Several buffer elements may be connected in parallel or in series to form buffers of larger volume having improved calorie storage capacity. Different forms of buffer can be imagined to facilitate the integration of this component on the place of use, apartment, house, factory, community, etc ... that is approximately CAP 200 or remote thereof for example in a false ceiling or in lost roofs.

FIGS. 2 and 4 show two nonlimiting exemplary embodiments: a cylindrical general geometry stamp in FIG. 2 and a parallelepipedal geometry stamp in FIG.

The configuration of the first circulation path 320 and the second circulation path 330 passing through the buffer 300 can also be the subject of numerous embodiments, optimized to favor the transfer of calories between the fluids without, however, leading to losses of pressure too much. important.

According to the particular embodiment represented in FIGS. 2 and 3, the first circulation path 320, intended to receive the air extracted from a building, consists of a sheath of large circular section 321 located at the center of the buffer. In the embodiment of Figure 4, an oval section conduit 321 is located at the bottom of the buffer. The second circulation path 330 is according to the embodiment of FIGS. 2 and 4, constituted by a distributor and a collector situated respectively at the two ends of the buffer and interconnected by a set of multiple tubes generally parallel to each other. extending along the longitudinal axis of the pad. The pipes 332 may also be spiral around the main pipe 321. In Figures 2, 3 and 4 attached, only the manifold 331 and the tubes 332 connecting the manifold to the distributor (not shown in the figures to simplify the illustration) are represented.

Preferably, the outside air which forms the third fluid circulating in the second circulation path 330 in the multiple tubes 332, between the manifold 331 and the distributor, is driven against the flow of the second hot fluid in the first circulation path. 320.

By way of non-limiting example, the cylindrical geometry buffer shown in FIG. 1 may have a length of the order of 50 cm and a diameter of about 30 cm leading to a volume of first thermal storage fluid 312. the order of 10 liters. Also as a non-limiting example, the heat buffer shown in FIG. 4, of rectangular section, may have a length of 50 cm, a height of 30 cm and a width of 20 cm leading to a volume of first thermal storage fluid 312 of the order of 24 liters. Those skilled in the art will understand from reading the present description that the invention makes it possible to recover the calories available in the ambient air of the house, in particular the air evacuated by mechanical ventilation. This air is used to load the heat buffer 300 permanently. The available calories in the buffer are then transferred to the intermittently cold external air fluid to recover this heat during the commissioning of the heat pump. The preheated outside air at the buffer 300 is used at the evaporator 210. FIG. 5 shows the temperature variation of the storage fluid 312 contained in a heat buffer 300 and the variation as a result of the temperature of the outside air (third fluid) passing through the buffer 300 during the shutdown and operation of the heat pump. During the shutdown of the heat pump, the temperature of the storage fluid 312 contained in the buffer 300 rises progressively.

During this time, the temperature of the third fluid remains constant, since the fan 350 is not put into service. On the other hand, during the commissioning of the heat pump 200 and the fan 350, the outside air (third fluid) is circulated through the buffer 300. The temperature rise of this fluid directed towards the Evaporator 210 consequently reduces the temperature of stored fluid 312 in buffer 300. The simulation of FIG. 5 is carried out over 24 hours for a buffer with a capacity of 72 liters consisting of three buffer modules of the type illustrated in FIG. figure 4. The simulation is performed for air extracted from a kitchen at 20 ° C with a flow rate of 50m 3 per hour for an outside air circuit put into service to supply the evaporator 210 with a flow of 400m 3 per hour at 5 ° C originally.

The curve of FIG. 5 shows a rather sudden drop in the internal temperature of the buffer 300 because the heat is recovered for the production of domestic hot water. In the context of the above-mentioned simulation, the energy recovered is of the order of 1.4 kWh / day. Of course, this energy depends on the volume of the buffer 300 and the temperature and the constant flow rate of the ambient air that charges the buffer and the temperature and the outside air flow that passes through the buffer intermittently before being directed towards the evaporator 210. FIGS. 6 and 7 show variant embodiments for which the heat buffer 300 of general geometry of rectangular section has, at least on a portion of the first and second circulation paths, channels concentric for a direct thermal exchange between the second hot fluid formed of the air extracted by the ventilation and the third fluid intended to be intermittently directed towards the evaporator 210 of the heat pump 200. In FIG. two circulation paths 320 and 330 are circular, whereas in FIG. 7 the sections of the ducts of the circulation paths are rectangular s.

In Figures 6 and 7, the concentric pipes are referenced 320a and 330a. In the same FIGS. 6 and 7, there are also shown pipe sections 330b, 330c, 330d and 330e which are in direct contact for heat exchange with the fluid 312 of the internal volume of the buffer 300.

Of course, the present invention is not limited to the particular embodiments which have just been described but extends to any variant within its spirit.

In particular, those skilled in the art can consider numerous alternative embodiments of the ducts components of the two circulation paths 320 and 330 in order to optimize the heat transfer between the fluids flowing in these respective paths and the first storage fluid. thermal 312 placed in the buffer 300, and if necessary according to the embodiment of Figures 6 and 7 by direct heat exchange between the two fluids. For this purpose, it is possible to provide, in particular, ducts carrying external fins immersed in the thermal storage fluid 312 as well as convolutional paths for both the path 320 and the path 330. Furthermore, the present invention concerns a pump heat is not limited to the field of thermodynamic water heaters, but applies to all areas of use of a heat pump. The buffer 300 according to the present invention can in fact be coupled with all types of heat pumps (for example a heat pump intended to produce domestic hot water (DHW) or a heat pump intended for a heating function ) and even with a reversible heat pump (heating and cooling, air conditioning). The buffer 300 according to the present invention improves the performance of heat pumps and cold groups. It is sufficient for applications other than those of thermodynamic water heaters, to associate with the condenser 230 not a balloon to store the ECS as described above in the context of a preferred embodiment, but any other calorie recovery means for example a flow of water or air that carries the calories for the desired use (heating or other).

Claims (11)

REVENDICATIONS1. Heat pump installation (200), characterized in that it comprises, upstream of the evaporator (210) of the heat pump, a heat buffer tank (300) comprising a closed volume which houses a first storage fluid thermal device (312), a first circulation path (320) of a second hot fluid adapted to ensure a transfer of heat from the hot fluid to the storage fluid during circulation of the hot fluid in the first circulation path (320) and a second circulation path (330) of a third fluid to be intermittently directed to the evaporator (210) of the heat pump to take heat from the heat buffer (300) during circulation. third fluid in the second circulation path (330). 2. Installation according to claim 1, characterized in that the thermal storage fluid (312) placed in the closed volume of the heat buffer (300) is water or a phase change material. 3. Installation according to one of claims 1 or 2, characterized in that the second hot fluid is air extracted from a building. 4. Installation according to one of claims 1 to 3, characterized in that the third fluid to be directed intermittently to the evaporator (210) of the heat pump (200) after passing through the heat buffer tank (300) and selected from the group consisting of: outdoor air drawn by the heat pump, water from a buried geothermal sensor, or water from a water table or river. 5. Installation according to one of claims 1 to 4, characterized in that the first flow path (320) for the second hot fluid comprises a single wide sheath (321) longitudinally through the heat buffer (300) while the second circulation path (330) of the third fluid is formed by a distributor and a collector (331) disposed at the ends of the buffer and connected by a plurality of tubes (332). 6. Installation according to one of claims 1 to 5, characterized in that at least a portion of the second flow path (330) is against the current of the first flow path (320). 7. Installation according to one of claims 1 to 6, characterized in that the second hot fluid is continuously driven in the first flow path (320). 8. Installation according to one of claims 1 to 7, characterized in that a portion of the first circulation path (320) and the second circulation path (330) are concentric. 9. Installation according to one of claims 1 to 8, characterized in that the heat buffer (300) is formed of several modules interconnected. 10. Heat buffer for the implementation of an installation according to one of claims 1 to 9, characterized in that it comprises a closed volume which houses a first thermal storage fluid (312), a first a circulation path (320) of a second hot fluid adapted to ensure a transfer of heat from the hot fluid to the storage fluid during circulation of the hot fluid in the first circulation path (320) and a second circulation path ( 330) of a third fluid to be intermittently directed to the evaporator (210) of the heat pump (200) for taking heat from the heat buffer (300) during the circulation of the third fluid in the second circulation path (330). 11. Application of a heat pump installation according to one of claims 1 to 9 and / or the heat buffer according to claim 10 to the realization of a thermodynamic water heater or a heating installation or air conditioning.