Absorption type heat pump device

Abstract

To provide an absorption type heat pump device capable of suppressing fluctuation of an outlet temperature of cooling water flowing out of an evaporator for cooling a cooling space.SOLUTION: An absorption type heat pump device 100 includes: an evaporator 3; an absorber 4; a regenerator 1; a condenser 2; a concentration acquisition part 71 for acquiring the concentration of an absorbent; a cooling part 90 provided at the evaporator 3, including a cooling water circulation passage 91 where cooling water circulates, and cooling a cooling space C; a first rotary mechanism 5 including a first heat exchange part 50 arranged in the evaporator 3 and performing heat exchange between the cooling water and a refrigerant, and a first rotating body 53 for applying the refrigerant to the first heat exchange part 50; a second rotary mechanism 6 including a second heat exchange part 60 arranged in the absorber 4 and a second rotating body 62 for applying the refrigerant to the second heat exchange part 60; and a control part 72 for adjusting the rotational frequency of the first rotating body 53 and the rotational frequency of the second rotating body 62 based on the concentration of the absorbent acquired in the concentration acquisition part 71, and adjusting the heat quantity which the refrigerant recovers from the cooling water in the evaporator 3.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an absorption heat pump device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been known an absorption heat pump device that uses an absorbing liquid capable of absorbing vapor generated when a refrigerant evaporates (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses an absorption heat pump device including a regenerator, a condenser, an evaporator, and an absorber. The above-mentioned condenser is provided with a circulation path through which cooling water flows. The above-mentioned absorption heat pump device recovers heat from the cooling water by performing heat exchange between the refrigerant in the circulation path and the cooling water. The above-mentioned absorption heat pump device sends the cooling water in the circulation path discharged from the inside of the evaporator to a heat exchanger arranged in a cooling space to cool the cooling space. In the above-mentioned regenerator, the absorbing liquid (diluted liquid) that has absorbed the refrigerant is heated using a heat source such as exhaust heat in order to separate the absorbing liquid (diluted liquid) into refrigerant vapor and absorbing liquid (concentrated liquid). The above-mentioned absorption heat pump device uses exhaust gas from an engine as a heat source. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-138028 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the absorption refrigerator described in the above Patent Document 1, since the heat source such as exhaust gas used for heating in the regenerator is prone to change in heat quantity, it is not possible to supply a stable amount of heat to the regenerator, and separation of the absorption liquid and the refrigerant vapor becomes unstable. As a result, the cycle of the absorption heat pump device becomes unstable, and the outlet temperature of the cooling water coming out of the evaporator to cool the cooling space becomes unstable, so an improvement is required.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide an absorption heat pump device that is capable of suppressing fluctuations in the outlet temperature of the cooling water that leaves the evaporator to cool the cooling space. [Means for solving the problem]

[0007] In order to achieve the above object, an absorption heat pump device in one aspect of the present invention is an absorption heat pump device that absorbs refrigerant vapor with an absorbing liquid, and includes an evaporator that evaporates refrigerant, an absorber that absorbs the refrigerant vapor evaporated in the evaporator into the absorbing liquid, a regenerator that heats a solution of refrigerant and absorbing liquid with a predetermined heat source to separate the refrigerant vapor and absorbing liquid, thereby regenerating the absorbing liquid and returning it to the absorber, a condenser that condenses the refrigerant vapor generated in the regenerator, a concentration acquisition unit that acquires the concentration of the absorbing liquid returned from the regenerator to the absorber, and a cooling water circulation path provided in the evaporator and through which cooling water circulates. and a control unit that performs control to adjust the amount of heat recovered by the refrigerant from the cooling water in the evaporator by adjusting at least one of the rotation speeds of the first and second rotors based on the concentration of the absorption liquid acquired by the concentration acquisition unit, by adjusting at least one of the rotation speeds of the first and second rotors based on the concentration of the absorption liquid acquired by the concentration acquisition unit.

[0008] In the absorption heat pump device according to one aspect of the present invention, as described above, when the evaporator includes a first rotation mechanism that exchanges heat between the cooling water and the refrigerant, the control unit performs control to adjust the rotation speed of the first rotor that applies the refrigerant by rotation to the first heat exchange unit that exchanges heat between the cooling water and the refrigerant based on the concentration of the absorbing liquid. This makes it possible to change the degree of evaporation of the refrigerant in the evaporator, and therefore it is possible to directly adjust the amount of heat recovered by the refrigerant from the cooling water in the evaporator. In addition, when the absorber includes a second rotation mechanism that exchanges heat between the cooling water and the refrigerant, the control unit performs control to adjust the rotation speed of the second rotor that applies the refrigerant by rotation to the second heat exchange unit that exchanges heat between the cooling water and the refrigerant based on the concentration of the absorbing liquid. This makes it possible to change the degree of absorption of the refrigerant in the absorber (the degree to which refrigerant vapor is drawn from the evaporator) and therefore it is possible to indirectly adjust the amount of heat recovered by the refrigerant from the cooling water in the evaporator. Here, the outlet temperature of the cooling water from the evaporator is determined by the flow rate (flow velocity) of the cooling water in the cooling section and the amount of heat that the refrigerant recovers from the cooling water in the evaporator. As a result of the above, it is possible to suppress fluctuations in the outlet temperature of the cooling water from the evaporator to cool the cooling space.

[0009] In an absorption heat pump device according to one aspect of the present invention, as described above, the cooling unit includes a cooling water pump that circulates cooling water in the cooling water circuit, and the control unit is configured to adjust the flow rate of cooling water flowing through the cooling water circuit, in addition to at least one of the rotation speed of the first rotating body and the rotation speed of the second rotating body, to suppress fluctuations in the outlet temperature of the cooling water exiting the evaporator.

[0010] With this configuration, the flow rate of the cooling water flowing through the cooling water circulation passage can also be adjusted, so that the fluctuation in the outlet temperature of the cooling water leaving the evaporator can be more effectively suppressed.

[0011] In one aspect of the absorption heat pump device of the present invention, as described above, the device comprises at least one of a first rotation mechanism and a second rotation mechanism, and further comprises a memory unit that stores operating information in which at least one of the rotation speed of the first rotor and the rotation speed of the second rotor is preset in accordance with the concentration of the absorption liquid, and the control unit is configured to adjust at least one of the rotation speed of the first rotor and the rotation speed of the second rotor based on the operating information, thereby adjusting the amount of heat recovered by the refrigerant from the cooling water in the evaporator.

[0012] With this configuration, the operating information stored in the memory unit can be used to adjust at least one of the rotation speeds of the first rotating body and the second rotating body toward a predetermined control target value, thereby easily suppressing fluctuations in the outlet temperature of the cooling water leaving the evaporator to cool the cooling space.

[0013] In this case, the operating information preferably includes a plurality of operating modes in which the rotation speeds of the first rotor and the second rotor are set to correspond to each of a predetermined concentration range of the absorbing liquid, and the control unit is configured to switch the operating mode as the concentration range of the predetermined absorbing liquid changes, thereby adjusting the amount of heat recovered by the refrigerant from the cooling water in the evaporator.

[0014] With this configuration, in each operating mode, for which a predetermined absorption liquid concentration range is set, the rotation speed of the first rotating body and the rotation speed of the second rotating body do not fluctuate while the predetermined operating mode is maintained, thereby preventing frequent changes in the operating state of the absorption heat pump device and stabilizing the operating state.

[0015] In the absorption heat pump device according to the above aspect, the following configuration is also possible.

[0016] (Additional note 1) In the absorption heat pump device according to the above aspect, the device is provided with a second rotation mechanism and further includes a pressure sensor that measures the pressure in the evaporator or the absorber, and the control unit is configured to adjust the rotation speed of the second rotating body so that the measurement value of the pressure sensor becomes a predetermined value.

[0017] With this configuration, the operation of the second rotor can be controlled based on the pressure in the evaporator or absorber, which varies in direct relation to the rotation speed of the second rotor.

[0018] (Additional note 2) In the absorption heat pump device according to the above aspect, the device includes both a first rotation mechanism including a first electric motor that rotates a first rotating body, and a second rotation mechanism including a second electric motor that rotates a second rotating body, and the control unit is configured to at least one of adjust the rotation speed of the first rotating body by varying the output rotation speed of the first electric motor, and adjust the rotation speed of the second rotating body by varying the output rotation speed of the second electric motor.

[0019] With this configuration, it is possible to directly control the first electric motor to control the rotation speed of the first rotating body, and to directly control the second electric motor to control the rotation speed of the second rotating body.

[0020] (Additional note 3) In the absorption heat pump device according to the above aspect, the concentration acquisition unit includes a temperature sensor that measures the temperature of the absorption liquid returned from the regenerator to the absorber, and a density sensor that measures the density of the absorption liquid returned from the regenerator to the absorber, or a pressure sensor that measures the pressure in the evaporator or the absorber, and is configured to acquire the concentration of the absorption liquid from the measurement value of the temperature sensor and the measurement value of the density sensor or the pressure sensor.

[0021] With this configuration, the concentration of the absorbing liquid can be easily obtained by using the temperature sensor and the density sensor or the pressure sensor. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram showing an overall configuration of an absorption heat pump device according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing a configuration of an evaporator in the embodiment. [Diagram 3] FIG. 2 is a cross-sectional view showing a configuration of an absorber in the embodiment. [Figure 4] FIG. 2 is a diagram showing the configuration of an evaporator and an absorber in the embodiment. [Diagram 5] 5 is a diagram for explaining a control target value for each operation mode included in operation information stored in a storage unit in the embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0024] (Embodiment) The configuration of an absorption heat pump device 100 according to an embodiment of the present invention will be described with reference to Figs.

[0025] (Configuration of Absorption Heat Pump Device) The absorption heat pump device 100 according to the embodiment of the present invention is configured to absorb refrigerant vapor with an absorbing liquid. In the absorption heat pump device 100, water as a refrigerant and an aqueous solution of lithium bromide (LiBr) as an absorbing liquid are used, as an example. The absorption heat pump device 100 is configured to be mounted on a vehicle (not shown) such as a passenger car or a bus equipped with an engine as a heat source. The absorption heat pump device 100 is configured to use (recover) the heat of high-temperature exhaust gas discharged from the engine to heat the absorbing liquid (dilute liquid). In addition, the absorption heat pump device may be applied to a facility such as a factory and configured to heat the regenerator using exhaust heat discharged from the facility. Note that, in FIG. 1, for ease of understanding, a configuration related to cooling of the cooling space C by the absorption heat pump device 100 is shown, and other configurations are omitted.

[0026] 1, the absorption heat pump device 100 includes a regenerator 1 (enclosed in a two-dot chain line frame), a condenser 2, an evaporator 3, and an absorber 4. The absorption heat pump device 100 also includes a first rotation mechanism 5 disposed in the evaporator 3 to promote evaporation of the refrigerant, and a second rotation mechanism 6 disposed in the absorber 4 to promote absorption of the refrigerant by the absorption liquid.

[0027] The absorption heat pump device 100 also includes a pressure sensor 70 that measures the pressure in the evaporator 3 or the absorber 4 , a concentration acquisition unit 71 , a control unit 72 , and a storage unit 73 .

[0028] Here, the control unit 72 of the absorption heat pump device 100 of this embodiment is configured to adjust the rotation speed of a first rotor 53 (described later) of the first rotation mechanism 5 and the rotation speed of a second rotor 62 (described later) of the second rotation mechanism 6 based on the concentration of the absorption liquid acquired by the concentration acquisition unit 71, thereby performing control to adjust the amount of heat recovered by the refrigerant in the evaporator 3 from the cooling water in a cooling water circulation path 91 (described later) provided in the evaporator 3.

[0029] As a result, the control unit 72 is configured to suppress fluctuations in the outlet temperature of the cooling water in the cooling water circulation path 91 discharged from the evaporator 3 even when the amount of heat of the predetermined heat source that heats the regenerator 1 is unstable (when the concentration of the absorbing liquid after regeneration fluctuates). The control unit 72 will be described in detail later.

[0030] The regenerator 1 has a role of separating refrigerant vapor (high-temperature water vapor) from the absorbing liquid. The regenerator 1 is configured to heat the solution of refrigerant and absorbing liquid with a predetermined heat source and separate it into refrigerant vapor and absorbing liquid, thereby regenerating the absorbing liquid (concentrated liquid) and returning it to the absorber 4. The condenser 2 is configured to condense (liquefy) the refrigerant vapor generated in the regenerator 1. The evaporator 3 is configured to evaporate (vaporize) the refrigerant that has become condensed water under low-temperature and low-pressure conditions. The absorber 4 is configured to absorb the refrigerant vapor evaporated in the evaporator 3 into the absorbing liquid supplied in a concentrated liquid state.

[0031] The regenerator 1 includes a heating section 10 that heats the solution of the refrigerant and the absorbing liquid, and a gas-liquid separation section 11 that separates the refrigerant vapor from the heated absorbing liquid. In the heating section 10, heat is exchanged between the absorbing liquid and the high-temperature exhaust gas flowing through the exhaust pipe from the engine. That is, the refrigerant and the absorbing liquid are heated by the exhaust gas (exhaust heat).

[0032] The absorption heat pump device 100 also includes a refrigerant vapor passage 80 connecting the regenerator 1 (gas-liquid separation section 11) and the evaporator 3, a liquid refrigerant passage 81 connecting the condenser 2 and the evaporator 3, an absorbing liquid passage 82 connecting the regenerator 1 and the absorber 4 and returning the absorbing liquid (concentrated liquid) regenerated in the regenerator 1 to the absorber 4, and an absorbing liquid passage 83 connecting the regenerator 1 and the absorber 4 and sending a solution of the absorbing liquid and refrigerant to the regenerator 1. The absorbing liquid passage 83 is provided with a pump 83a for pumping the solution.

[0033] The absorption heat pump device 100 also includes a cooling section 90 and a heat dissipation section 95 .

[0034] The cooling unit 90 is provided in the evaporator 3, and includes a circular cooling water circulation path 91 through which cooling water circulates, a cooling water pump 92 provided in the cooling water circulation path 91, and a heat exchanger 93 that emits cool air.

[0035] The cooling unit 90 is configured to cool the cooling space C (such as the vehicle interior space) by a heat exchange unit 93 arranged in the cooling space C. The cooling water pump 92 is configured to circulate the cooling water in a cooling water circulation path 91. The cooling water in the cooling water circulation path 91 exchanges heat with the refrigerant in the first rotation mechanism 5 in the evaporator 3, thereby recovering heat and cooling the cooling water. The heat exchange unit 93 has a heat exchanger and a cooling fan.

[0036] In addition, it is preferable that the cooling unit 90 suppresses fluctuations in the outlet temperature of the cooling water of the cooling unit 90 exiting the evaporator 3 so that the cooling of the cooling space C in the heat exchange unit 93 that emits cold air is stabilized. For this reason, it is preferable that the cooling unit 90 suppresses fluctuations in the amount of heat recovered by the refrigerant from the cooling water in the evaporator 3 so that the cooling in the heat exchange unit 93 that emits cold air is stabilized.

[0037] The heat dissipation unit 95 is provided so as to straddle the absorber 4 and the condenser 2. The heat dissipation unit 95 includes a ring-shaped cooling water circulation path 96 through which cooling water circulates, a cooling water pump 97 provided in the cooling water circulation path 96, and a heat exchange unit 98 that releases hot air to an external space different from the cooling space C.

[0038] The cooling water pump 97 is configured to circulate the cooling water in the cooling water circulation path 96. The cooling water in the cooling water circulation path 96 is heated by heat exchange with the refrigerant and the absorbing liquid solution in the second rotation mechanism 6 in the absorber 4. The heat exchange unit 98 has a heat exchanger and a heat dissipation fan.

[0039] In this embodiment, the evaporator 3 and the absorber 4 are disposed adjacent to each other and integrally configured as shown in Figures 1 and 4. The structures of the evaporator 3 and the absorber 4, the interiors of which are kept in a vacuum state (absolute pressure of 1 kPa or less), will be described in detail below.

[0040] (Configuration of evaporator and first rotation mechanism) 2 and 4, the evaporator 3 includes a container 31 that maintains the inside in a vacuum state. A first rotation mechanism 5 is disposed inside the evaporator 3 (container 31).

[0041] The first rotation mechanism 5 includes a first heat exchange unit 50 having a plurality of disk-shaped heat exchangers 51, a refrigerant sending unit 52, a first rotor 53, and a first electric motor 54 that rotates the first rotor 53. The refrigerant sending unit 52 is configured to pump up and transport the refrigerant supplied into the container 31.

[0042] The heat exchangers 51 are arranged at equal intervals along the X-axis direction. In the first heat exchange section 50, the individual heat exchangers 51 are connected to each other on the Y1 side and the Y2 side in the horizontal direction by a cooling water inlet passage 91a and a cooling water outlet passage 91b. The cooling water inlet passage 91a and the cooling water outlet passage 91b are part of the cooling water circulation passage 91 of the cooling section 90.

[0043] The cooling water that flows into the evaporator 3 from the cooling water introduction passage 91a is distributed to each heat exchanger 51 and, while flowing through the heat exchanger 51 from the Y1 side to the Y2 side, is cooled by the latent heat of evaporation when the refrigerant (water) supplied (applied) to the heat transfer surface 51a of the heat exchanger 51 turns into refrigerant vapor (low-temperature water vapor), and is collected in the cooling water outlet passage 91b and discharged from the evaporator 3. In the heat exchange section 93 of the cooling section 90, the air from the cooling fan is cooled by the cooling water flowing through the heat exchanger. Then, the cooled air is blown out into the cooling space as cold air.

[0044] The first rotor 53 includes a shaft member 53a, a plurality of branch members 53b, and a plurality of brushes 53c.

[0045] The shaft member 53a has a hollow structure with an internal flow path extending linearly. One end of the shaft member 53a (X1 side) is connected to the rotation center of the refrigerant delivery part 52. One branch member 53b integrally includes a plurality of branch portions that branch out and extend from the shaft member 53a toward the outside in the rotational radial direction. The plurality of branch portions of the branch member 53b have a hollow structure with an internal flow path and a plurality of supply holes that open at the ends of the internal flow paths.

[0046] The lower part (Z2 side) of the refrigerant delivery part 52 is immersed in the refrigerant (water) stored in the container 31. The refrigerant delivery part 52 has a spiral blade part therein, and is configured to pump up the refrigerant by rotation and supply it to the internal flow path of the shaft member 53a.

[0047] The refrigerant delivery section 52 is rotated with the rotation of the shaft member 53a driven by the first electric motor 54. As a result, the refrigerant (water) is pumped up and delivered to the internal flow path of the shaft member 53a. The first rotor 53 is also rotated with the rotation of the shaft member 53a. Therefore, the refrigerant flowing through the internal flow path of the shaft member 53a in the direction of the arrow X2 is diverted to the internal flow path of the branch member 53b by utilizing the centrifugal force generated with the rotation of the first rotor 53, and then flows toward the outside in the rotational radius direction and is supplied to the heat transfer surface 51a of the heat exchanger 51 through the supply hole at the end. Then, immediately after the refrigerant is supplied to the heat transfer surface 51a, the refrigerant is applied in a thin film form to each of the heat transfer surfaces 51a of the multiple heat exchangers 51 by the brush 53c which is rotated in the direction of the arrow R.

[0048] (Configuration of absorber and second rotating mechanism) As shown in Figures 3 and 4, the absorber 4 includes a container 41 that maintains the inside in a vacuum state. The internal space of the container 41 communicates with the internal space of the container 31 of the evaporator 3, and is maintained at the same pressure. The pressures of the containers 31 and 41 are maintained at an extremely low pressure (for example, 1 / 100 of atmospheric pressure) so as to activate the evaporation of the refrigerant in the evaporator 3. The pressures of the containers 31 and 41 are measured by a pressure sensor 70.

[0049] A second rotation mechanism 6 is disposed in the absorber 4 (container 41). The second rotation mechanism 6 includes a second heat exchange section 60 having a plurality of heat exchangers 61, a second rotor 62, and a second electric motor 63 that rotates the second rotor 62.

[0050] Here, as described above, the second rotation mechanism 6 promotes the absorption of the refrigerant by the absorbing liquid in the absorber 4. The absorption of the refrigerant is promoted as the rotation speed of the second rotor 62 of the second rotation mechanism 6 increases. For this reason, there is a certain relationship between the rotation speed of the second rotor 62 of the second rotation mechanism 6 (the rotation speed of the second electric motor 63) and the measurement value of the pressure sensor 70. Therefore, the control unit 72 is configured to adjust the rotation speed of the second rotor 62 (the rotation speed of the second electric motor 63) so that the measurement value of the pressure sensor 70 becomes a predetermined pressure.

[0051] An absorption liquid passage 82 for supplying the absorption liquid (concentrated liquid) from the gas-liquid separation section 11 of the regenerator 1 to the absorber 4, and an absorption liquid passage 83 for supplying the absorption liquid in which the refrigerant has been absorbed in the absorber 4 to the regenerator 1 (heating section 10) are connected to the bottom of the container 41. In addition, the absorption liquid (dilute liquid obtained by diluting the refrigerant by the concentrated liquid) is stored at the bottom of the container 41.

[0052] The heat exchangers 61 are arranged at equal intervals along the X-axis direction. In the second heat exchange section 60, the individual heat exchangers 61 are connected to each other by a cooling water inlet passage 96a arranged at the bottom on the Z2 side and a cooling water outlet passage 96b arranged at the top on the Z1 side. The cooling water inlet passage 96a and the cooling water outlet passage 96b are part of the cooling water circulation passage 96 of the heat dissipation section 95.

[0053] The cooling water that flows into the absorber 4 from the cooling water inlet passage 96a is distributed to each heat exchanger 61 via the cooling water inlet passage 96a, flows from the Z2 side to the Z1 side within the heat exchanger 61, gathers in the cooling water outlet passage 96b, and is discharged to the outside of the evaporator 3. In the heat exchange section 98 of the heat dissipation section 95, the air from the heat dissipation fan dissipates heat by the cooling water flowing through the heat exchanger. Then, the heated air is blown out to the outside.

[0054] The second rotating body 62 includes a shaft member 62a, a holding member 62b, and a brush 62c.

[0055] The holding member 62b includes a plurality of branches extending radially at intervals of approximately 90 degrees from the outer surface. The brush 62c is fixed to the branches of the holding member 62b. The brush 62c is arranged such that the bristles face the heat transfer surface 61a of the heat exchanger 61. When the shaft member 62a is rotated by the drive of the second electric motor 63, the second rotor 62 rotates.

[0056] As a result, the absorbing liquid (LiBr aqueous solution) stored at the bottom of the container 41 is successively pumped up by each brush 62c which is rotated together with the rotation of the second rotor 62 driven by the second electric motor 63. Then, the absorbing liquid held by the brushes 62c is applied in the form of a thin film along the heat transfer surface 61a of the heat exchanger 61.

[0057] (Configuration of concentration acquisition unit) The concentration acquisition unit 71 shown in FIG. 1 is configured to acquire the concentration of the absorbing liquid (concentrated liquid) returned from the regenerator 1 to the absorber 4. As an example, the concentration acquisition unit 71 includes a temperature sensor 71a that measures the temperature of the absorbing liquid returned from the regenerator 1 to the absorber 4, and a density sensor 71b that measures the density of the absorbing liquid returned from the regenerator 1 to the absorber 4. As an example, the temperature sensor 71a and the density sensor 71b are provided in the middle of the absorbing liquid passage 82. The concentration acquisition unit 71 is configured to acquire the concentration of the absorbing liquid from the measurement value of the temperature sensor 71a and the measurement value of the density sensor 71b. The concentration acquisition unit may include a pressure sensor that measures the pressure in the evaporator or the absorber instead of the density sensor.

[0058] Here, the concentration of the absorbing liquid (concentrated liquid) acquired by the concentration acquisition unit 71 varies with changes in the heat quantity of a predetermined heat source that provides heating in the heating unit 10 of the regenerator 1. When the heat quantity of the predetermined heat source is large, heating can be performed effectively in the heating unit 10 of the regenerator 1, and therefore separation of the refrigerant and the absorbing liquid can be effectively promoted. Therefore, the concentration of the absorbing liquid (concentrated liquid) acquired by the concentration acquisition unit 71 becomes high.

[0059] On the other hand, when the heat quantity of the predetermined heat source is small, the heating unit 10 of the regenerator 1 cannot sufficiently heat the refrigerant and the absorbing liquid, and therefore the concentration of the absorbing liquid (concentrated liquid) acquired by the concentration acquisition unit 71 becomes low.

[0060] (Storage unit configuration) The storage unit 73 has memories such as ROM and RAM. The storage unit 73 stores operation information 73a in which the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62 are set in advance in correspondence with the concentration of the absorbing solution. The operation information 73a includes a plurality of operation modes in which the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62 are set in correspondence with each of predetermined concentration ranges of the absorbing solution. Details will be described later.

[0061] (Control Unit Configuration) As an example, the control unit 72 has a computing unit such as a CPU. Before describing the control unit 72, factors that cause fluctuations in the outlet temperature of the cooling water of the cooling unit 90 exiting from the evaporator 3 will be described.

[0062] The outlet temperature of the cooling water of the cooling section 90 exiting the evaporator 3 is determined by the flow rate (flow velocity) of the cooling water of the cooling section 90 and the amount of heat (hereinafter referred to as "amount of recovered heat") recovered from the cooling water of the cooling section 90 by the refrigerant (first rotating mechanism 5) in the evaporator 3. The flow rate (flow velocity) of the cooling water of the cooling section 90 is adjusted by a cooling water pump 92 of the cooling section 90. When the flow rate (flow velocity) of the cooling water of the cooling section 90 is increased, the outlet temperature of the cooling water of the cooling section 90 exiting the evaporator 3 increases. When the flow rate (flow velocity) of the cooling water of the cooling section 90 is decreased, the outlet temperature of the cooling water of the cooling section 90 exiting the evaporator 3 decreases.

[0063] The amount of recovered heat is determined by the heat transfer efficiency between the refrigerant in the evaporator 3 and the cooling water in the cooling section 90, and the temperature of the refrigerant in the evaporator 3. The heat transfer efficiency can be controlled by the rotation speed of the first rotor 53 of the first rotation mechanism 5 in the evaporator 3 (the rotation speed of the first electric motor 54). The temperature of the refrigerant in the evaporator 3 is determined by the pressure in the evaporator 3 (in the absorber 4).

[0064] The pressure in the evaporator 3 is determined by the concentration of the absorbing liquid in the refrigerant (solution) placed in the evaporator 3 and the temperature of the refrigerant. The temperature of the refrigerant in the evaporator 3 is determined by the amount of heat transfer between the cooling water in the cooling section 90 and the refrigerant in the evaporator 3, and can be controlled by the rotation speed of the second rotor 62 of the second rotation mechanism 6 in the absorber 4 (the rotation speed of the second electric motor 63).

[0065] As a result, the outlet temperature of the cooling water of the cooling section 90 leaving the evaporator 3 is determined by four factors: the flow rate (flow velocity) of the cooling water of the cooling section 90, which can be adjusted by the cooling water pump 92 of the cooling section 90; the rotation speed of the first rotor 53 of the first rotating mechanism 5 in the evaporator 3 (the rotation speed of the first electric motor 54); the rotation speed of the second rotor 62 of the second rotating mechanism 6 in the absorber 4 (the rotation speed of the second electric motor 63); and the concentration of the absorbing liquid, which varies depending on the amount of exhaust heat used for heating in the regenerator 1.

[0066] Therefore, the control unit 72 of this embodiment is configured to suppress fluctuations in the outlet temperature of the cooling water of the cooling section 90 exiting the evaporator 3 by adjusting the rotation speed of the first rotating body 53 of the first rotating mechanism 5 in the evaporator 3 (the rotation speed of the first electric motor 54) and the rotation speed of the second rotating body 62 of the second rotating mechanism 6 in the absorber 4 (the rotation speed of the second electric motor 63) to suppress fluctuations in the amount of heat recovered by the refrigerant (first rotating mechanism 5) from the cooling water of the cooling section 90 within the evaporator 3.

[0067] Furthermore, the control unit 72 of this embodiment is configured to adjust the flow rate of the cooling water flowing through the cooling water circulation path 91 of the cooling section 90, in addition to the rotation speed of the first rotating body 53 and the rotation speed of the second rotating body 62, to suppress fluctuations in the outlet temperature of the cooling water exiting the evaporator 3.

[0068] Specifically, the control unit 72 is configured to adjust the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62 based on the operation information 73a stored in the storage unit 73, thereby adjusting the amount of heat recovered by the refrigerant from the coolant in the evaporator 3. At this time, the control unit 72 also controls the drive of the coolant pump 92 based on the operation information 73a stored in the storage unit 73.

[0069] More specifically, as shown in FIG. 5, three driving modes are preset according to the concentration range of the absorbing liquid: a "dilution mode" in which the concentration of the absorbing liquid is high; a "steady state mode" in which the concentration of the absorbing liquid is lower than that in the dilution mode; and a "concentration mode" in which the concentration of the absorbing liquid is lower than that in the steady state mode.

[0070] As an example, the set concentration at which the steady mode switches to the dilution mode is when the concentration of the absorbing solution becomes 61.7% or more. Conversely, the set concentration at which the dilution mode switches to the steady mode is when the concentration of the absorbing solution becomes less than 61.2%. The reason why the set concentrations at which the steady mode and the dilution mode switch are different from each other is to prevent chattering caused by frequent switching between the steady mode and the dilution mode.

[0071] The set concentration at which the steady mode switches to the concentrated mode is when the concentration of the absorbing solution falls below 59.5%. Conversely, the set concentration at which the concentrated mode switches to the steady mode is when the concentration of the absorbing solution reaches 60.0% or more. The reason why the set concentrations at which the steady mode and the concentrated mode switch are different from each other is to prevent chattering, which occurs when the steady mode and the concentrated mode switch frequently.

[0072] In the "dilution mode", the control unit 72 controls the driving of the cooling water pump 92 so that the flow rate of the cooling water circulation path 91 of the cooling unit 90, which is the control target value, becomes α1 [L / min]. As an example, α1 is 6.0 [L / min].

[0073] In the "dilution mode", the rotation speed of the second rotating body 62 (second electric motor 63) is controlled by the control unit 72 so that the measurement value of the pressure sensor 70, which is the control target value, becomes β1 [Pa]. As an example, β1 is 700 [Pa]. That is, the control unit 72 is configured to adjust the rotation speed of the second rotating body 62 so that the measurement value of the pressure sensor 70 becomes a predetermined value. In addition, the control unit 72 is configured to adjust the rotation speed of the second rotating body 62 by varying the output rotation speed of the second electric motor 63. Note that β1, which is the control target value, may be the rotation speed of the second rotating body (second electric motor) instead of the measurement value of the pressure sensor.

[0074] In the "dilution mode", the control unit 72 controls the rotation speed of the first rotor 53 (first electric motor 54), which is a control target value, to be γ1 [rpm]. That is, the control unit 72 is configured to adjust the rotation speed of the first rotor 53 by varying the output rotation speed of the first electric motor 54. As an example, γ1 is 90 [rpm].

[0075] In the "steady mode", the control unit 72 controls the operation of the cooling water pump 92 so that the flow rate of the cooling water circulation path 91 of the cooling unit 90, which is the control target value, becomes α2 [L / min]. α2 is a value less than α1. As an example, α2 is 3.0 [L / min].

[0076] In the "steady mode", the control unit 72 controls the rotation speed of the second rotating body 62 (second electric motor 63) so that the measurement value of the pressure sensor 70, which is the control target value, becomes β2 [Pa]. β2 is a value equal to or greater than β1. As an example, β2 is 700 [Pa]. Note that β2, which is the control target value, may be the rotation speed of the second rotating body (second electric motor) instead of the measurement value of the pressure sensor.

[0077] In the "steady mode", the control unit 72 controls the rotation speed of the first rotor 53 (first electric motor 54), which is the control target value, to γ2 [rpm]. γ2 is a value less than γ1. As an example, γ2 is 60 [rpm].

[0078] In the "concentration mode", the control unit 72 controls the driving of the cooling water pump 92 so that the flow rate of the cooling water circulation path 91 of the cooling unit 90, which is the control target value, becomes α3 [L / min]. α3 is a value less than α2. As an example, α3 is 1.0 [L / min].

[0079] In the "concentration mode", the control unit 72 controls the rotation speed of the second rotating body 62 (second electric motor 63) so that the measurement value of the pressure sensor 70, which is the control target value, becomes β3 [Pa]. β3 is a value larger than β2. As an example, β3 is 850 [Pa]. Note that β3, which is the control target value, may be the rotation speed of the second rotating body (second electric motor) instead of the measurement value of the pressure sensor.

[0080] In the "concentration mode", the control unit 72 controls the rotation speed of the first rotor 53 (first electric motor 54), which is a control target value, to γ3 [rpm]. γ3 is a value less than γ2. As an example, γ3 is 30 [rpm].

[0081] (Effects of the embodiment) In this embodiment, the following effects can be obtained.

[0082] In this embodiment, as described above, when the evaporator 3 includes the first rotating mechanism 5 that exchanges heat between the cooling water and the refrigerant, the control unit 72 performs control to adjust the rotation speed of the first rotating body 53 that applies the refrigerant by rotation to the first heat exchange unit 50 that exchanges heat between the cooling water and the refrigerant based on the concentration of the absorbing liquid. This makes it possible to change the degree of evaporation of the refrigerant in the evaporator 3, and therefore it is possible to directly adjust the amount of heat recovered by the refrigerant from the cooling water in the evaporator 3. Furthermore, when the absorber 4 includes the second rotating mechanism 6 that exchanges heat between the cooling water and the refrigerant, the control unit 72 performs control to adjust the rotation speed of the second rotating body 62 that applies the refrigerant by rotation to the second heat exchange unit 60 that exchanges heat between the cooling water and the refrigerant based on the concentration of the absorbing liquid. This makes it possible to change the degree of absorption of the refrigerant in the absorber 4 (the degree to which refrigerant vapor is drawn from the evaporator 3) and therefore it is possible to indirectly adjust the amount of heat recovered by the refrigerant from the cooling water in the evaporator 3. Here, the outlet temperature of the cooling water of the cooling section 90 coming out of the evaporator 3 is determined by the flow rate (flow velocity) of the cooling water of the cooling section 90 and the amount of heat that the refrigerant recovers from the cooling water in the evaporator 3. Therefore, as a result of the above, it is possible to suppress fluctuations in the outlet temperature of the cooling water coming out of the evaporator 3 to cool the cooling space C.

[0083] In this embodiment, as described above, the cooling unit 90 includes the cooling water pump 92 that circulates the cooling water in the cooling water circulation path 91, and the control unit 72 is configured to adjust the flow rate of the cooling water flowing through the cooling water circulation path 91 in addition to at least one of the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62, thereby suppressing fluctuations in the outlet temperature of the cooling water leaving the evaporator 3. This makes it possible to adjust the flow rate of the cooling water flowing through the cooling water circulation path 91, so that the cooling unit 90 is configured to more effectively suppress fluctuations in the outlet temperature of the cooling water leaving the evaporator 3.

[0084] In this embodiment, as described above, the device includes at least one of the first rotation mechanism 5 and the second rotation mechanism 6, and further includes a storage unit 73 that stores operation information 73a in which at least one of the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62 is preset in accordance with the concentration of the absorption liquid, and the control unit 72 is configured to adjust at least one of the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62 based on the operation information 73a to adjust the amount of heat recovered by the refrigerant from the cooling water in the evaporator 3. This makes it possible to use the operation information 73a stored in the storage unit 73 to adjust at least one of the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62 toward a preset control target value, and therefore it is possible to easily suppress fluctuations in the outlet temperature of the cooling water discharged from the evaporator 3 to cool the cooling space C.

[0085] In this embodiment, as described above, the operation information 73a includes a plurality of operation modes in which the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62 are set in correspondence with each of the predetermined concentration ranges of the absorbing liquid, and the control unit 72 is configured to switch the operation mode as the predetermined concentration range of the absorbing liquid changes, and adjust the amount of heat recovered by the refrigerant from the cooling water in the evaporator 3. As a result, in each operation mode in which the predetermined concentration range of the absorbing liquid is set, the rotation speed of the first rotor 53 and the rotation speed of the second rotor 62 do not fluctuate while the predetermined operation mode is maintained, and therefore it is possible to suppress frequent changes in the operation state of the absorption heat pump device 100 and stabilize the operation state.

[0086] As described above, this embodiment includes the second rotation mechanism 6 and further includes a pressure sensor 70 that measures the pressure in the evaporator 3 or the absorber 4, and the control unit 72 is configured to adjust the rotation speed of the second rotor 62 so that the measurement value of the pressure sensor 70 becomes a predetermined value. This makes it possible to control the operation of the second rotor 62 based on the pressure in the evaporator 3 or the absorber 4 that varies in direct relation to the rotation speed of the second rotor 62.

[0087] As described above, this embodiment includes both the first rotation mechanism 5 including the first electric motor 54 that rotates the first rotating body 53 and the second rotation mechanism 6 including the second electric motor 63 that rotates the second rotating body 62, and the control unit 72 is configured to at least one of adjust the rotation speed of the first rotating body 53 by varying the output rotation speed of the first electric motor 54 and adjust the rotation speed of the second rotating body 62 by varying the output rotation speed of the second electric motor 63. This makes it possible to directly control the first electric motor 54 to control the rotation speed of the first rotating body 53 and directly control the second electric motor 63 to control the rotation speed of the second rotating body 62.

[0088] In this embodiment, as described above, the concentration acquisition unit 71 includes a temperature sensor 71a that measures the temperature of the absorbing liquid returned from the regenerator 1 to the absorber 4, and a density sensor 71b that measures the density of the absorbing liquid returned from the regenerator 1 to the absorber 4, or a pressure sensor that measures the pressure in the evaporator 3 or the absorber 4, and is configured to acquire the concentration of the absorbing liquid from the measurement value of the temperature sensor 71a and the measurement value of the density sensor 71b or the pressure sensor. This makes it possible to easily acquire the concentration of the absorbing liquid by the temperature sensor 71a and the density sensor 71b or the pressure sensor.

[0089] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims rather than the description of the above embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0090] For example, in the above embodiment, the absorption heat pump device includes both the first rotation mechanism and the second rotation mechanism, but the present invention is not limited to this. In the present invention, the absorption heat pump device may include only one of the first rotation mechanism and the second rotation mechanism.

[0091] In the above embodiment, in order to suppress fluctuations in the outlet temperature of the cooling water from the evaporator, the flow rate of the cooling water flowing through the cooling water circulation path is adjusted by controlling the drive of the cooling water pump of the cooling part, but the present invention is not limited to this. In the present invention, it is not necessary to adjust the flow rate of the cooling water flowing through the cooling water circulation path by controlling the drive of the cooling water pump of the cooling part.

[0092] In the above embodiment, an example is shown in which the rotation speed of the first rotor of the first rotation mechanism (the rotation speed of the first electric motor), the rotation speed of the second rotor of the second rotation mechanism (the rotation speed of the second electric motor), and the flow rate of the cooling water flowing through the cooling water circulation path of the cooling unit are controlled to be constant within a predetermined concentration range of the absorbing liquid, but the present invention is not limited to this. In the present invention, the rotation speed of the first rotor of the first rotation mechanism (the rotation speed of the first electric motor), the rotation speed of the second rotor of the second rotation mechanism (the rotation speed of the second electric motor), and the flow rate of the cooling water flowing through the cooling water circulation path of the cooling unit may be configured to constantly vary in response to fluctuations in the concentration of the absorbing liquid. In short, the operation mode described in the above embodiment may not be provided.

[0093] In addition, although the above embodiment does not mention adjusting the heat amount of a specified heat source that performs heating in the regenerator, the control unit may adjust the heat amount of a specified heat source that performs heating in the regenerator to suppress fluctuations in the outlet temperature of the cooling water of the cooling section exiting the evaporator. [Explanation of symbols]

[0094] 1 regenerator 2 Condenser 3. Evaporator 4. Absorber 5 First Rotation Mechanism 6 Second Rotation Mechanism 50 (First rotating mechanism) first heat exchange section 53 First rotating body (of the first rotating mechanism) 60 (Second heat exchange section of the second rotating mechanism) 62 (Second rotating body of the second rotating mechanism) 71 Concentration acquisition section 72 Control section 73 Memory section 73a Driving Information 90 Cooling section 91 (cooling section) cooling water circuit 92 (cooling section) cooling water pump 100 Absorption heat pump device C Cooling space

Claims

1. An absorption heat pump device that absorbs refrigerant vapor with an absorption liquid, an evaporator that evaporates a refrigerant; an absorber for absorbing the refrigerant vapor evaporated in the evaporator into an absorbing liquid; a regenerator for heating a solution of the refrigerant and the absorbing liquid by a predetermined heat source and separating the refrigerant vapor and the absorbing liquid to regenerate the absorbing liquid and return it to the absorber; a condenser for condensing the refrigerant vapor generated in the regenerator; A concentration acquisition unit that acquires a concentration of the absorbing solution returned from the regenerator to the absorber; a cooling section that is provided in the evaporator and includes a cooling water circulation path through which cooling water circulates and cools a cooling space; at least one of a first rotation mechanism disposed in the evaporator, the first heat exchange unit performing heat exchange between the cooling water and a refrigerant and a first rotor that applies the refrigerant to the first heat exchange unit by rotation, and a second rotation mechanism disposed in the absorber, the second heat exchange unit including a second rotor that applies the refrigerant to the second heat exchange unit by rotation; a control unit that performs control to adjust the amount of heat recovered by the refrigerant from the cooling water in the evaporator by adjusting at least one of the rotation speed of the first rotor and the rotation speed of the second rotor based on the concentration of the absorption liquid acquired by the concentration acquisition unit.

2. the cooling unit includes a cooling water pump that circulates the cooling water in the cooling water circulation path, 2. The absorption heat pump apparatus according to claim 1, wherein the control unit is configured to adjust a flow rate of the cooling water flowing through the cooling water circulation path in addition to at least one of the rotation speed of the first rotating body and the rotation speed of the second rotating body, to suppress fluctuations in an outlet temperature of the cooling water exiting the evaporator.

3. At least one of the first rotation mechanism and the second rotation mechanism is provided, A storage unit is further provided that stores operational information in which at least one of a rotation speed of the first rotor and a rotation speed of the second rotor is preset in accordance with a concentration of the absorbing solution, 2. The absorption heat pump device according to claim 1, wherein the control unit is configured to adjust at least one of the rotation speed of the first rotating body and the rotation speed of the second rotating body based on the operating information, thereby adjusting the amount of heat recovered by the refrigerant from the cooling water in the evaporator.

4. the operation information includes a plurality of operation modes in which the rotation speed of the first rotor and the rotation speed of the second rotor are set corresponding to each of predetermined concentration ranges of the absorbing solution, 4. The absorption heat pump device according to claim 3, wherein the control unit is configured to switch the operation mode in response to a change in the concentration range of the predetermined absorption liquid, thereby adjusting the amount of heat recovered by the refrigerant from the cooling water in the evaporator.

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