JP2019027338A - Rankine cycle device - Google Patents

Abstract

To provide a technology suitable to supply gaseous working fluid to a gas bearing in a state of securing rotational power, in an expander.SOLUTION: An internal space 104 of a first container 112d of an expander 112 stores an expansion mechanism 112a, a dynamo 116, a rotational shaft 112b and a gas bearing 112c. A first circulation passage 201 where working fluid flows, and a second circulation passage 202 where working fluid flows are provided. In the first circulation passage 201, a pump 115, a first connection point p1, an evaporator 111, a first inlet 105i, the expansion mechanism 112a, a first outlet 105o, and a condenser 113 are arranged in this order. In the second circulation passage 202, the pump 115, the first connection pint p1, a second container 112e, a second inlet 106i, the internal space 104, a second outlet 106o, and the condenser 113 are arranged in this order. Between working fluid in the second container 112e and the dynamo 116, heat is exchanged.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a Rankine cycle device.

  Various studies have been conducted on Rankine cycle devices using gas bearings. Patent Document 1 discloses an example of such an apparatus.

  FIG. 6 is a system diagram of the Rankine cycle device of Patent Document 1. This apparatus has a boiler 9, a superheater 10, an expander 2, a condenser 7, and a pump 8.

  The boiler 9 is a steam generation means. The boiler 9 heats and boils the working fluid. As a result, the working fluid becomes saturated steam. Next, the superheater 10 turns the working fluid into superheated steam. Next, the expander 2 adiabatically expands the working fluid. Thereby, the working fluid becomes low-pressure saturated steam. Moreover, the turbine of the expander 2 rotates. Next, the condenser 7 condenses the working fluid. Next, the pump 8 pressurizes the working fluid. The pressurized working fluid flows into the boiler 9 again.

  FIG. 7 is a structural diagram of the expander 2 and the like. The expander 2 is a centrifugal expander. The working fluid that has become superheated steam in the superheater 10 is supplied to the turbine 55 via the steam inlet 57. The turbine 55 adiabatically expands the working fluid. As a result, the working fluid becomes saturated steam. The working fluid that has become saturated steam flows into the condenser 7 via the steam outlet 58.

  The expander casing 56, the expander back casing 27, and the expander bearing 52 form an expansion chamber. In this expansion chamber, the turbine 55 rotates at a high speed. A turbine 55 is fixed to one end of the shaft of the expander 2, that is, the turbine shaft 53. The turbine shaft 53 is supported by an expander bearing 52 and an expander thrust bearing 51.

  Both bearings 52 and 51 are static pressure gas bearings. There is a gap between the bearings 52 and 51 and the turbine shaft 53. The saturated steam generated in the boiler 9 is introduced into the gap via the bearing steam conduit 60 and the steam passage 54. This saturated steam is used as a working fluid for both bearings 52 and 51. The working fluid flows through the gap between the throttle and shaft of the bearing, the adjacent space 70 and the low pressure steam conduit 59 to the steam outlet 58.

JP-A-2-050055

  However, according to studies by the present inventors, there is room for improvement in the technique of Patent Document 1 from the viewpoint of securing rotational power in the expander.

  An object of the present disclosure is to provide a technique suitable for supplying a working fluid in a gaseous state to a gas bearing while securing rotational power in an expander.

This disclosure
Rankine cycle device,
The Rankine cycle device includes a pump, an evaporator, an expander, and a condenser.
The expander includes an expansion mechanism, a generator, a rotating shaft, a gas bearing, a first container, and a second container,
The generator includes a rotor and a stator,
The rotating shaft connects the expansion mechanism and the rotor,
The gas bearing supports the rotating shaft,
The first container includes an internal space, a first inlet, a first outlet, a second inlet, and a second outlet,
The internal space houses the expansion mechanism, the generator, the rotating shaft, and the gas bearing,
The second container is attached to the first container;
In the Rankine cycle device, a first circulation path through which the working fluid flows and a second circulation path through which the working fluid flows are configured,
In the first circulation path, the pump, the first connection point, the evaporator, the first inlet, the expansion mechanism, the first outlet, and the condenser appear in this order,
In the second circulation path, the pump, the first connection point, the second container, the second inlet, the internal space, the second outlet, and the condenser appear in this order. ,
A Rankine cycle device in which the working fluid in the second container and the generator exchange heat is provided.

  The technology according to the present disclosure is suitable for supplying a working fluid in a gaseous state to a gas bearing while securing rotational power in the expander.

Configuration diagram of Rankine cycle device according to Embodiment 1 Configuration diagram of Rankine cycle device according to Embodiment 2 Configuration diagram of Rankine cycle device according to Embodiment 3 Configuration diagram of Rankine cycle device according to Embodiment 4 Mollier diagram for explaining the operation of the decompressor System diagram of Rankine cycle device of Patent Document 1 Structure diagram of expander etc. in Patent Document 1

(Knowledge by the present inventors)
In the Rankine cycle device of Patent Document 1, in the boiler 9, heat is applied to the working fluid, and the working fluid becomes saturated steam. Then, the saturated steam is supplied to both the bearings 52 and 51 via the bearing steam conduit 60 while maintaining the heat.

  However, if it does in that way, a part of heat which generate | occur | produced in the boiler 9 will not be supplied to the turbine 55, but will be utilized for vaporization of the working fluid supplied to a gas bearing. For this reason, the rotational power obtained by the turbine 55 is reduced by the amount of heat used for the vaporization.

  An object of the present disclosure is to provide a technique suitable for supplying a working fluid in a gaseous state to a gas bearing while securing rotational power in an expander.

The first aspect of the present disclosure is:
Rankine cycle device,
The Rankine cycle device includes a pump, an evaporator, an expander, and a condenser.
The expander includes an expansion mechanism, a generator, a rotating shaft, a gas bearing, a first container, and a second container,
The generator includes a rotor and a stator,
The rotating shaft connects the expansion mechanism and the rotor,
The gas bearing supports the rotating shaft,
The first container includes an internal space, a first inlet, a first outlet, a second inlet, and a second outlet,
The internal space houses the expansion mechanism, the generator, the rotating shaft, and the gas bearing,
The second container is attached to the first container;
In the Rankine cycle device, a first circulation path through which the working fluid flows and a second circulation path through which the working fluid flows are configured,
In the first circulation path, the pump, the first connection point, the evaporator, the first inlet, the expansion mechanism, the first outlet, and the condenser appear in this order,
In the second circulation path, the pump, the first connection point, the second container, the second inlet, the internal space, the second outlet, and the condenser appear in this order. ,
A Rankine cycle device in which the working fluid in the second container and the generator exchange heat is provided.

  According to the first aspect, the liquid working fluid can be supplied from the pump to the second container through the first connection point by the second circulation path. The second container is attached to the first container, and a generator is accommodated in the internal space of the first container. For this reason, heat exchange can be performed between the working fluid in the second container and the generator. By this heat exchange, the generator can be cooled and the working fluid can be heated and vaporized. Moreover, the working fluid in a gaseous state can be supplied from the second container to the internal space of the first container through the second circulation path. For this reason, the working fluid in a gaseous state can be supplied to the gas bearing accommodated in the internal space.

  Thus, according to the first aspect, the working fluid in the gas state can be supplied to the gas bearing. Moreover, not the heat of the evaporator but the heat of the generator can be used to vaporize the working fluid. For this reason, rotational power is easily secured in the expansion mechanism. For the above reasons, the technology according to the first aspect is suitable for supplying a working fluid in a gaseous state to a gas bearing while securing rotational power in the expander. Moreover, it is suitable also for ensuring the electric power generation amount in a generator.

The second aspect of the present disclosure includes, in addition to the first aspect,
The Rankine cycle device includes a gas-liquid separator,
In the Rankine cycle device, a third circulation path through which the working fluid flows is configured,
In the second circulation path, the pump, the first connection point, the second container, the inlet of the gas-liquid separator, the gas outlet of the gas-liquid separator, the second inlet, An internal space, the second outlet, and the condenser appear in this order,
In the third circulation path, the pump, the first connection point, the second container, the inlet of the gas-liquid separator, the liquid outlet of the gas-liquid separator, and the condenser are: A Rankine cycle device that appears in this order is provided.

  During the period when the power generation amount of the generator is small, the heat generation amount of the generator is small. In this period, the working fluid flowing out from the second container can be in a gas-liquid two-phase state. Even in such a case, according to the gas-liquid separator of the second aspect, the gas-liquid two-phase working fluid can be separated into the gas-state working fluid and the liquid-state working fluid. And the working fluid of a gaseous state can be supplied to a gas bearing.

In the third aspect of the present disclosure, in addition to the first aspect or the second aspect,
The Rankine cycle device includes a reheater,
The reheater includes a heat application path and a heat recovery path,
In the first circulation path, the pump, the first connection point, the heat recovery path, the evaporator, the first inlet, the expansion mechanism, the first outlet, and the heat application path. And the condenser appear in this order,
In the second circulation path, the pump, the first connection point, the second container, the second inlet, the internal space, the second outlet, the heat application path, and the condenser And appear in this order,
A Rankine cycle device is provided in which the working fluid in the heat application path and the working fluid in the heat recovery path exchange heat.

  In the third aspect, the working fluid heated in the second container flows into the heat application path of the reheater via the internal space of the first container. In the reheater, heat is exchanged between the working fluid in the heat recovery path and the working fluid in the heat application path. By this heat exchange, the working fluid in the heat recovery path is heated. The heated working fluid flows to the evaporator and the expansion mechanism. For this reason, the rotational power obtained by the expansion mechanism can be increased by the amount of heat given to the working fluid in the heat recovery path. Moreover, the power generation amount in the generator can be increased by this amount. Thus, according to the 3rd aspect, the heat of a generator can be contributed to rotation power increase and power generation amount increase.

According to a fourth aspect of the present disclosure, in addition to any one of the first aspect to the third aspect,
The Rankine cycle device includes a decompressor,
In the second circulation path, the pump, the first connection point, the decompressor, the second container, the second inlet, the internal space, the second outlet, and the condenser , Appear in this order, and a Rankine cycle device is provided.

  According to the decompressor of the fourth aspect, the decompressed working fluid can be supplied to the second container. This decompression reduces the saturation temperature of the working fluid. Here, the saturation temperature refers to a temperature at which the working fluid starts to evaporate. Since the saturation temperature is lowered, the working fluid in the second container can be vaporized even when the heat given from the generator is relatively small. For this reason, according to the 4th aspect, it is easy to vaporize the working fluid in a 2nd container also in the period when the heat_generation | fever of a generator is small and the temperature of a generator is low.

According to a fifth aspect of the present disclosure, in addition to any one of the first aspect to the fourth aspect,
The Rankine cycle device has a cross section perpendicular to the axial direction of the rotating shaft, and has a cross section in which the generator, a wall constituting the first container, and the second container are arranged in this order. Providing equipment.

  According to the fifth aspect, heat exchange can be suitably performed between the working fluid in the second container and the generator.

  Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the following embodiment.

(Embodiment 1)
FIG. 1 is a configuration diagram of a Rankine cycle device 200 according to the first embodiment.

  In the Rankine cycle apparatus 200, a working fluid flows. An organic working fluid can be suitably used as the working fluid. Examples of the organic working fluid include halogenated hydrocarbons, hydrocarbons, alcohols and the like. Examples of the halogenated hydrocarbon include R-123, R-245fa, R-1233zd, R-365mfc, and the like. Examples of the hydrocarbon include alkanes such as propane, butane, pentane, and isopentane. Examples of the alcohol include ethanol. These organic working fluids may be used alone or in combination of two or more.

  Rankine cycle apparatus 200 includes a pump 115, an evaporator 111, an expander 112, and a condenser 113. Rankine cycle apparatus 200 includes a first temperature sensor 151, a second temperature sensor 152, and a third temperature sensor 153. Rankine cycle apparatus 200 includes a first valve 141, a second valve 142, a third valve 143, and a fourth valve 144. Rankine cycle apparatus 200 includes a heater 119. Rankine cycle device 200 includes a control device 150.

  The evaporator 111 is a heat exchanger that absorbs heat energy generated by a heat source (not shown). The evaporator 111 is, for example, a fin tube heat exchanger, and is disposed so as to be located on the path of the heat source gas. Heat exchange between the heat source gas and the working fluid of the Rankine cycle apparatus 200 is performed in the evaporator 111. As a result, the working fluid is heated and evaporated. For this heating, for example, waste heat energy discharged from facilities such as factories and incinerators can be used.

  The expander 112 includes an expansion mechanism 112a, a generator 116, a rotating shaft 112b, at least one gas bearing 112c, a first container 112d, and a second container 112e.

  The expansion mechanism 112a expands the working fluid. Thereby, the expansion energy of the working fluid is converted into rotational power.

  The generator 116 includes a rotor 116a and a stator 116b. Typically, the stator 116b is provided in the vicinity of the rotor 116a. In the example of FIG. 1, the stator 116b surrounds the rotor 116a. The stator 116b is fixed to the first container 112d. The generator 116 is, for example, a permanent magnet synchronous generator.

  The rotation shaft 112b connects the expansion mechanism 112a and the rotor 116a. For this reason, the rotating shaft 112b and the rotor 116a rotate with the expansion mechanism 112a by the rotational power obtained by the expansion mechanism 112a. When the rotor 116a rotates, a rotating magnetic field is generated. When the rotating magnetic field is generated, electricity is generated in the stator 116b. In this way, the generator 116 is driven by the expansion mechanism 112a, and the generator 112 generates power. Electricity generated in the stator 116b is supplied to the outside through wiring connected to the stator 116b.

  At least one gas bearing 112c supports the rotating shaft 112b. Specifically, the at least one gas bearing 112c rotatably supports the rotating shaft 112b.

  In the present embodiment, there are a plurality of gas bearings 112c. The plurality of gas bearings 112c include at least one radial gas bearing and at least one thrust gas bearing. In the example of FIG. 1, the number of radial gas bearings is two, and the number of thrust gas bearings is one. However, the position and number of the radial gas bearing and the thrust gas bearing are not limited to this.

  The radial gas bearing supports the rotating shaft 112b from the radial direction of the rotating shaft 112b. The thrust gas bearing supports the rotating shaft 112b from the axial direction of the rotating shaft 112b. The two radial gas bearings are provided in the vicinity of the attachment position of the rotor 116a to the rotating shaft 112b. With respect to the axial direction of the rotating shaft 112b, the two radial gas bearings are located on opposite sides of the rotor 116a. With respect to the axial direction of the rotating shaft 112b, the thrust gas bearing is provided between the expansion mechanism 112a and the rotor 116a.

  Note that the number of gas bearings 112c included in the expander 112 may be one. The expander 112 may have a gas bearing 112c and a bearing that is not a gas bearing.

  There are two types of gas bearings: dynamic pressure type and static pressure type. The dynamic pressure type gas bearing supports the rotating shaft by dynamic pressure generated by the rotation of the rotating shaft. Gas is continuously supplied to the hydrostatic gas bearing from the outside of the bearing. The static pressure type gas bearing supports the rotating shaft by the static pressure of the supply gas. A dynamic pressure type gas bearing can be used as the gas bearing 112c. Moreover, a static pressure type gas bearing can also be used as the gas bearing 112c.

  According to the present embodiment, the gas bearing 112c can be surrounded by gas. Accordingly, it is possible to prevent a situation in which the liquid around the gas bearing 112c is abnormally compressed and the gas bearing 112c is burned. This effect can be exhibited both when the type of the gas bearing 112c is a static pressure type and a dynamic pressure type. The reason why the surroundings of the gas bearing 112c can be gas will be described later.

  The first container 112d includes an internal space 104, a first inlet 105i, a first outlet 105o, a second inlet 106i, and a second outlet 106o. The first inlet 105i, the first outlet 105o, the second inlet 106i, and the second outlet 106o communicate with the internal space 104, respectively.

  The internal space 104 houses the expansion mechanism 112a, the generator 116, the rotating shaft 112b, and at least one gas bearing 112c.

  The second container 112e is attached to the first container 112d. Details of the second container 112e will be described later.

  The expander 112 is, for example, a volume type or a speed type expander. Examples of positive displacement expanders include scroll expanders, rotary expanders, screw expanders, and reciprocating expanders. The speed type expander is a so-called expansion turbine.

  The condenser 113 cools the high-temperature working fluid discharged from the expander 112 with another cooling medium such as air or water having a temperature lower than that of the working fluid. As the condenser 113, a well-known heat exchanger such as a finned tube heat exchanger, a plate heat exchanger, or a double tube heat exchanger can be used.

  The type of the condenser 113 is appropriately selected according to the type of the medium to be cooled. When the medium to be cooled is a liquid such as water, a plate heat exchanger or a double tube heat exchanger can be suitably used for the condenser 113. When the medium to be cooled is a gas such as air, a finned tube heat exchanger can be suitably used for the condenser 113.

  The pump 115 is an electric pump. The pump 115 can circulate a liquid working fluid. Specifically, the pump 115 sucks and pressurizes the working fluid that has flowed out of the condenser 113. Thereby, the pressurized working fluid is supplied to the evaporator 111.

  As the pump 115, a general positive displacement type or speed type pump can be used. Examples of the positive displacement pump include a piston pump, a gear pump, a vane pump, and a rotary pump. Examples of the speed type pump include a centrifugal pump, a mixed flow pump, and an axial flow pump.

  The pump 115 is not connected to the expander 112. That is, the rotating shaft of the pump 115 and the rotating shaft 112b of the expander 112 are separated. For this reason, the pump 115 can operate independently of the expander 112.

  In the Rankine cycle device 200, a first circulation path 201 through which a working fluid flows is configured. In the first circulation path 201, the pump 115, the first connection point p1, the evaporator 111, the first inlet 105i, the expansion mechanism 112a, the first outlet 105o, and the condenser 113 appear in this order. Specifically, in the first circulation path 201, the pump 115, the first connection point p1, the evaporator 111, the second temperature sensor 152, the second connection point p2, the first valve 141, and the first The inlet 105i, the expansion mechanism 112a, the first outlet 105o, the third connection point p3, the fourth connection point p4, the condenser 113, and the first temperature sensor 151 appear in this order. A plurality of pipes are used to connect these elements in the Rankine cycle apparatus 200.

  Hereinafter, elements appearing in the first circulation path 201 will be further described.

  The second temperature sensor 152 detects the temperature Te of the working fluid existing in a portion between the outlet of the evaporator 111 and the first inlet 105 i of the expander 112 in the first circulation path 201. The second temperature sensor 152 of the present embodiment detects the temperature Te directly by contacting the working fluid. However, the second temperature sensor 152 may indirectly detect the temperature Te by detecting the temperature of the wall forming the first circulation path 201. The wall is typically constituted by piping. The “portion between the outlet of the evaporator 111 and the first inlet 105i of the expander 112 in the first circulation path 201” includes the outlet of the evaporator 111 and the first inlet 105i of the expander 112.

  The position of the second temperature sensor 152 is not particularly limited as long as the second temperature sensor 152 can detect the temperature Te. The second temperature sensor 152 may be provided at any point in the above portion between the outlet of the evaporator 111 and the first inlet 105 i of the expander 112. Further, the second temperature sensor 152 can be provided at any location on the wall forming the portion. From the viewpoint of making the wiring of the expander 112 close to the wiring of the second temperature sensor 152 and making these wirings easy to handle, the second temperature sensor 152 can be provided at the first inlet 105i.

  The second temperature sensor 152 transmits a signal (detection signal) representing the temperature Te to the control device 150.

  The first valve 141 appears in a portion of the first circulation path 201 between the outlet of the evaporator 111 and the first inlet 105i. Specifically, the first valve 141 appears in a portion of the first circulation path 201 between the second connection point p2 and the first inlet 105i. The first valve 141 is a valve whose opening degree can be changed. By changing the opening degree of the first valve 141, the flow rate of the working fluid supplied to the expansion mechanism 112a of the expander 112 through the first inlet 105i can be adjusted. However, an electromagnetic on-off valve may be used as the first valve 141.

  According to the first valve 141, the supply amount of the working fluid to the expansion mechanism 112a of the expander 112 can be controlled. The first valve 141 can be referred to as an expander supply control valve 141.

  In this specification, the “opening degree” is expressed as a percentage of the cross-sectional area of the passage through which the working fluid passes when the cross-sectional area of the passage through which the working fluid passes is 100% when the valve is fully opened. Is.

  The first temperature sensor 151 detects the temperature Tp of the working fluid existing in a portion between the outlet of the condenser 113 and the inlet of the pump 115 in the first circulation path 201. The first temperature sensor 151 according to the present embodiment directly detects the temperature Tp by contacting the working fluid. However, the first temperature sensor 151 may indirectly detect the temperature Tp by detecting the temperature of the wall forming the first circulation path 201. The wall is typically constituted by piping. The “portion between the outlet of the condenser 113 and the inlet of the pump 115 in the first circulation path 201” includes the outlet of the condenser 113 and the inlet of the pump 115.

  The position of the first temperature sensor 151 is not particularly limited as long as the first temperature sensor 151 can detect the temperature Tp. The first temperature sensor 151 may be provided at any point in the above portion between the outlet of the condenser 113 and the inlet of the pump 115. Further, the first temperature sensor 151 can be provided at any location on the wall forming the portion.

  The first temperature sensor 151 transmits a detection signal of the temperature Tp to the control device 150.

  In the Rankine cycle device 200, a fourth circulation path 204 through which the working fluid flows is also configured. In the fourth circulation path 204, the pump 115, the first connection point p1, the evaporator 111, the second connection point p2, the second valve 142, the third connection point p3, and the condenser 113 are Appear in order.

  The fourth circulation path 204 has a portion extending from the second connection point p2 to the third connection point p3 via the second valve 142. This portion connects the second connection point p2 and the third connection point p3 while bypassing the expander 112. This part can be referred to as a bypass path 131. The second valve 142 can be referred to as a bypass valve 142. The upstream end of the bypass valve 142 is connected to the second connection point p2. The downstream end of the bypass valve 142 is connected to the third connection point p3. A bypass valve 142 appears in the bypass path 131.

  The second valve 142 is a valve whose opening degree can be changed. By changing the opening degree of the second valve 142, the flow rate of the working fluid that bypasses the expander 112 can be adjusted. However, an electromagnetic on-off valve may be used as the second valve 142.

  In the Rankine cycle device 200, a second circulation path 202 through which the working fluid flows is also configured. In the second circulation path 202, the pump 115, the first connection point p1, the second container 112e, the second inlet 106i, the internal space 104, the second outlet 106o, and the condenser 113 appear in this order. . Specifically, in the second circulation path 202, the pump 115, the first connection point p1, the second container 112e, the third valve 143, the heater 119, the third temperature sensor 153, and the second inlet 106i. The internal space 104, the second outlet 106o, the fourth valve 144, the fourth connection point p4, and the condenser 113 appear in this order.

  Part of the working fluid that has flowed out of the pump 115 flows into the internal space of the second container 112e via the first connection point p1 by the second circulation path 202. The working fluid in the second container 112e and the generator 116 exchange heat. The generator 116 is cooled by this heat exchange. Moreover, the working fluid in the second container 112e can be heated and vaporized by this heat exchange. Then, the working fluid in the gaseous state can be supplied from the second container 112e to the internal space 104 of the first container 112d through the second circulation path 202. For this reason, the working fluid in a gaseous state can be supplied to the gas bearing 112 c housed in the internal space 104.

  In the present embodiment, the partition 112p partitions the internal space 104 into the first region 104a and the second region 104b. The first region 104a houses the expansion mechanism 112a. In the first region 104a, a portion of the first circulation path 201 in the first container 112d is configured. The second region 104b houses the generator 116. The second region 104b houses at least one (typically all) of the gas bearings 112c included in the expander 112. In the second region 104b, a portion of the second circulation path 202 in the first container 112d is configured. The partition 112p suppresses leakage of the working fluid between the first circulation path 201 and the second circulation path 202.

  The specific configuration of the partition 112p is not particularly limited. In one specific example, the partition 112p includes a partition plate having a hole through which the rotating shaft 112b passes. In this specific example, there is a gap between the peripheral wall that defines the hole of the partition plate and the rotating shaft 112b. For this reason, the rotating shaft 112b can rotate without contacting the partition plate. The partition 112p may further include a seal such as a lip seal so that the leakage of the working fluid through the gap is reduced.

  In the present embodiment, Rankine cycle apparatus 200 has a cross section perpendicular to the axial direction of rotating shaft 112b, and generator 116, a wall constituting first container 112d, and second container 112e are arranged in this order. It has a cross section. For this reason, heat exchange can be suitably performed between the working fluid in the second container 112e and the generator 116.

  Specifically, the stator 116b is located around the rotor 116a. Then, the working fluid in the second container 112e and the stator 116b perform heat exchange. The Rankine cycle device 200 has a cross section perpendicular to the axial direction of the rotating shaft 112b, and the rotor 116a, the stator 116b, the wall constituting the first container 112d, and the second container 112e are in this order. It has a lined cross section.

  Typically, the volume of the internal space of the second container 112e is smaller than the volume of the internal space 104 of the first container 112d. In the present embodiment, the second container 112e has a cylindrical shape. The second container 112e may surround the first container 112d without a gap. As the second container 112e, a cooling jacket type can be used.

  In the example of FIG. 1, the second container 112e is at least partially overlapped with the generator 116 (specifically, the stator 116b) and not overlapped with the gas bearing 112c with respect to the axial direction of the rotating shaft 112b. . According to such a position, heat exchange can be suitably performed between the working fluid in the second container 112e and the generator 116 (specifically, the stator 116b).

  In the present embodiment, at least one (specifically, all) of the gas bearings 112c included in the expander 112 is located between the second inlet 106i and the second outlet 106o in the axial direction of the rotating shaft 112b. It is in. In this way, the working fluid can be suitably supplied to the gas bearing 112c. The “position between the second inlet 106i and the second outlet 106o” includes the position of the second inlet 106i and the position of the second outlet 106o.

  The working fluid in a gaseous state is discharged from the internal space 104 through the second outlet 106o after being supplied to the gas bearing 112c. Thereafter, the working fluid flows into the condenser 113.

  In the portion of the second circulation path 202 extending from the first connection point p1 to the second container 112e, the working fluid used for cooling the generator 116 flows. This portion can be referred to as a cooling path 132. The upstream end of the cooling path 132 is connected to the first connection point p1. The downstream end of the cooling path 132 is connected to the second container 112e.

  A portion of the second circulation path 202 extending from the second container 112e to the second inlet 106i of the first container 112d supplies the gaseous working fluid to the internal space 104. This portion can be referred to as a gas supply path 133. The upstream end of the gas supply path 133 is connected to the second container 112e. The downstream end of the gas supply path 133 is connected to the second inlet 106i. In the gas supply path 133, a third valve 143, a heater 119, and a third temperature sensor 153 appear. Specifically, these elements appear in the gas supply path 133 in this order.

  The third valve 143 is a valve whose opening degree can be changed. By changing the opening degree of the third valve 143, the flow rate of the working fluid flowing through the gas supply path 133 can be adjusted. However, an electromagnetic on-off valve may be used as the third valve 143.

  According to the third valve 143, the supply amount of the working fluid in a gaseous state to the internal space 104 of the first container 112d can be controlled. The third valve 143 can be referred to as a gas supply control valve 143.

  The heater 119 heats the working fluid flowing through the gas supply path 133. The heater 119 may be provided inside a pipe that forms the gas supply path 133. In this case, the working fluid can be heated directly. The heater 119 may be provided outside the pipe. In this case, the working fluid can be heated indirectly through the piping.

  When the expander 112 is not operated, the generator 116 does not generate heat. For this reason, the working fluid is not vaporized in the second container 112e. Suppose that a liquid working fluid is supplied from the second container 112e to the gas bearing 112c. When the expander 112 is operated in this state, there is a possibility that seizure occurs in the gas bearing 112c. Therefore, in the present embodiment, the working fluid is heated by the heater 119 during the period from the start of the operation of the expander 112 until the working fluid in the gaseous state is generated in the second container 112e by the heat of the generator 116. Thereby, the working fluid in a gaseous state can be supplied to the first container 112d even during this period.

  The third temperature sensor 153 detects the temperature Tg of the working fluid existing in the gas supply path 133. The third temperature sensor 153 of the present embodiment directly detects the temperature Tg by contacting the working fluid. However, the third temperature sensor 153 may indirectly detect the temperature Tg by detecting the temperature of the wall forming the gas supply path 133. The wall is typically constituted by piping.

  The position of the third temperature sensor 153 is not particularly limited as long as the third temperature sensor 153 can detect the temperature Tg. The third temperature sensor 153 can be provided at any location in the gas supply path 133. Further, the third temperature sensor 153 can be provided at any location on the wall forming the portion.

  In the gas supply path 133 of the present embodiment, the third temperature sensor 153 is on the downstream side of the heater 119. For this reason, the amount of heating by the heater 119 can be confirmed by the third temperature sensor 153.

  The third temperature sensor 153 transmits a signal (detection signal) indicating the temperature Tg to the control device 150.

  The working fluid in the gaseous state is discharged from the internal space 104 by the portion of the second circulation path 202 that extends from the second outlet 106o of the first container 112d to the fourth connection point p4. This portion can be referred to as a gas exhaust path 134. The upstream end of the gas discharge path 134 is connected to the second outlet 106o. The downstream end of the gas discharge path 134 is connected to the fourth connection point p4. Further, the fourth valve 144 appears in the gas discharge path 134.

  The fourth valve 144 is a valve whose opening degree can be changed. By changing the opening degree of the fourth valve 144, the flow rate of the working fluid flowing through the gas discharge channel 134 can be adjusted. However, an electromagnetic on-off valve may be used as the fourth valve 144.

  According to the fourth valve 144, the discharge amount of the working fluid in a gaseous state from the second outlet 106o of the first container 112d can be controlled. The fourth valve 144 can be referred to as a gas discharge control valve 144.

  In the present embodiment, the fourth connection point p4, which is the connection destination of the gas discharge path 134, is in the portion between the third connection point p3 and the inlet of the condenser 113 in the first circulation path 201. In this way, it is difficult to hinder the flow of the working fluid flowing out from the internal space 104 of the first container 112d through the first outlet 105o. However, the fourth connection point p4 can be set at any part of the first circulation path 201 between the first outlet 105o and the inlet of the condenser 113. Further, the fourth connection point p4 can be set at any part of the bypass path 131 between the outlet of the second valve 142 and the third connection point p3.

  The control device 150 acquires the detected temperature Tp of the first temperature sensor 151, the detected temperature Te of the second temperature sensor 152, and the detected temperature Tg of the third temperature sensor 153 as signals. The control device 150 can control the components of the Rankine cycle device 200 using these signals. Further, the control device 150 can control the components of the Rankine cycle device 200 based on the power generation amount of the generator 116.

  For example, the control device 150 increases or decreases the rotation speed of the pump 115, increases or decreases the rotation speed of the expander 112, or increases or decreases the cooling amount of the working fluid in the condenser 113 based on the detected temperature Tp. In addition, the control device 150 estimates the temperature of the working fluid flowing into the second container 112e based on the detected temperature Tp. The control device 150 adjusts the opening degrees of the third valve 143 and the fourth valve 144 based on the estimated temperature. Through the adjustment of the opening, the cooling amount of the generator 116 in the second container 112e can be controlled. In one specific example, the control device 150 decreases the opening degree of the third valve 143 and the fourth valve 144 as the detected temperature Tp of the first temperature sensor 151 is lower.

  For example, when the detected temperature Te exceeds a preset threshold temperature, the control device 150 opens the third valve 143 (and the fourth valve 144) and starts heating by the heater 119. Thereby, the working fluid in a gaseous state starts to be supplied to the gas bearing 112 c in the internal space 104.

  For example, the control device 150 opens the first valve 141 and starts the operation of the expander 112 when the detected temperature Tg exceeds a preset threshold temperature. The control device 150 controls the heating amount of the heater 119 based on the detected temperature Tg.

  Control based on the power generation amount of the generator 116 will be described. In one example, the opening degree of the third valve 143 is adjusted according to the amount of power generation. Specifically, the opening degree of the third valve 143 is increased as the power generation amount is larger. By doing so, the flow rate of the working fluid flowing through the gas supply path 133 increases as the power generation amount increases. Thereby, it can prevent that the temperature of the generator 116 rises excessively.

  Further, the opening degree of the fourth valve 144 can be controlled according to the amount of power generated by the generator 116 while controlling the opening degree of the third valve 143 in this way. Specifically, the opening degree of the fourth valve 144 can be increased as the power generation amount increases. Thereby, it is possible to avoid a situation in which the pressure in the internal space 104 of the first container 112d continues to rise as the flow rate of the working fluid flowing through the gas supply path 133 increases.

  As described above, in the first circulation path 201, the pump 115 pumps and circulates the working fluid. The evaporator 111 heats the working fluid using heat from the heat source. Thereby, a working fluid will be in the state of gas, specifically superheated steam. A working fluid of superheated steam flows into the expander 112. The inflowing working fluid is adiabatically expanded in the expander 112. Thereby, a driving force is generated in the expansion mechanism 112a of the expander 112, and the expansion mechanism 112a operates. That is, the expansion energy is converted into mechanical energy by the expansion mechanism 112a. Along with the operation of the expansion mechanism 112a, the generator 116 operates to generate power. That is, mechanical energy is converted into electric energy by the generator 116. In short, the expansion mechanism 112a and the generator 116 convert the expansion energy into electric energy. The condenser 113 cools the working fluid discharged from the expansion mechanism 112a using cooling air, cooling water, or the like. As a result, the working fluid is condensed into a liquid state. The liquid working fluid is sucked into the pump 115.

  A part of the second circulation path 202 overlaps with a part of the first circulation path 201. In the second circulation path 202, a part of the working fluid in a liquid state flowing out from the pump 115 flows into the second container 112e via the first connection point p1 and the cooling path 132. The working fluid in the second container 112e and the generator 116 exchange heat. The working fluid in a gaseous state obtained after the heat exchange flows into the internal space 104 of the first container 112d via the gas supply path 133 and is supplied to the gas bearing 112c. Thereafter, the working fluid flows into the condenser 113 via the gas discharge path 134. The condenser 113 cools the working fluid that has passed through the second container 112e together with the working fluid that has passed through the expansion mechanism 112a. By opening the third valve 143 and the fourth valve 144, the working fluid passes through the second circulation path 202 based on the difference between the pressure of the working fluid at the outlet of the pump 115 and the pressure of the working fluid at the inlet of the condenser 113. Can circulate.

  In the generator 116, when electric energy is generated, iron loss and copper loss occur. These losses become thermal energy. That is, heat is generated in the generator 116 by the amount of energy corresponding to these losses, and the temperature of the generator 116 rises. If this temperature rise is left unattended, the material of the members constituting the generator 116 may be deteriorated by heat, or the members may be damaged. However, in the present embodiment, the generator 116 is cooled by heat exchange between the working fluid in the second container 112e and the generator 116. For this reason, deterioration and breakage of the constituent members of the generator 116 can be prevented.

  On the other hand, the working fluid in the second container 112e is heated and vaporized by heat exchange between the working fluid in the second container 112e and the generator 116. Thereby, it becomes possible to supply the working fluid in a gaseous state to the gas bearing 112 c existing in the accommodation space 104 of the expander 112.

  The working fluid supplied to the gas bearing 112c is discharged out of the internal space 104 of the first container 112d via the gas discharge path 134. Thereby, the pressure of the internal space 104 rises, the pressure difference between the outlet of the pump 115 and the internal space 104 is eliminated, and the situation where the working fluid cannot be supplied to the internal space 104 can be avoided.

  As described above, according to the present embodiment, the liquid working fluid can be supplied from the pump 115 to the second container 112e via the first connection point p1 by the second circulation path 202. The second container 112e is attached to the first container 112d, and the generator 116 is accommodated in the internal space 104 of the first container 112d. For this reason, heat exchange can be performed between the working fluid in the second container 112e and the generator 116. By this heat exchange, the generator 116 can be cooled, and the working fluid can be heated and vaporized. Further, the working fluid in a gaseous state can be supplied from the second container 112e to the internal space 104 of the first container 112d by the second circulation path 202. For this reason, the working fluid in a gaseous state can be supplied to the gas bearing 112 c housed in the internal space 104.

  Thus, according to this Embodiment, the working fluid of a gaseous state can be supplied to the gas bearing 112c. Moreover, not the heat of the evaporator 111 but the heat of the generator 116 can be used to vaporize the working fluid. For this reason, it is easy to ensure rotational power in the expansion mechanism 112a. For the above reasons, the technology according to the present embodiment is suitable for supplying the working fluid in the gaseous state to the gas bearing 112c while securing the rotational power in the expander 112. It is also suitable for securing the amount of power generated by the generator 116.

(Embodiment 2)
Next, the Rankine cycle apparatus of Embodiment 2 is demonstrated. FIG. 2 is a configuration diagram of Rankine cycle apparatus 300 according to the second embodiment. In the second embodiment, description of parts common to the first embodiment may be omitted.

  Rankine cycle apparatus 300 does not have heater 119. On the other hand, the Rankine cycle apparatus 300 includes a gas-liquid separator 117. The Rankine cycle device 300 includes a fifth valve 145 and a sixth valve 146.

  In the Rankine cycle device 300 of the present embodiment, in the first circulation path 201, the pump 115, the first connection point p1, the evaporator 111, the fifth connection point p5, the second temperature sensor 152, and the second Connection point p2, first inlet 105i, expansion mechanism 112a, first outlet 105o, third connection point p3, sixth connection point p6, fourth connection point p4, condenser 113, first The temperature sensor 151 appears in this order.

  In the Rankine cycle device 300, a second circulation path 302 is configured instead of the second circulation path 202. The second circulation path 302 is a path through which the working fluid flows. In the second circulation path 302, the pump 115, the first connection point p1, the second container 112e, the inlet 117i of the gas-liquid separator 117, the gas outlet 117og of the gas-liquid separator 117, and the second inlet 106i The internal space 104, the second outlet 106o, and the condenser 113 appear in this order. Specifically, in the second circulation path 302, the pump 115, the first connection point p1, the second container 112e, the inlet 117i, the gas outlet 117og, the third temperature sensor 153, the third valve 143, The second inlet 106i, the internal space 104, the second outlet 106o, the fourth valve 144, the fourth connection point p4, and the condenser 113 appear in this order.

  In the Rankine cycle device 300, a third circulation path 303 through which the working fluid flows is configured. In the third circulation path 303, the pump 115, the first connection point p1, the second container 112e, the inlet 117i of the gas-liquid separator 117, the liquid outlet 117ol of the gas-liquid separator 117, the condenser 113, Appear in this order. Specifically, in the third circulation path 303, the pump 115, the first connection point p1, the second container 112e, the inlet 117i of the gas-liquid separator 117, the liquid outlet 117ol of the gas-liquid separator 117, The fifth valve 145, the sixth connection point p6, and the condenser 113 appear in this order.

  A gas-liquid two-phase working fluid can flow into the gas-liquid separator 117 from the inlet 117i. The gas-liquid separator 117 separates this working fluid into a gaseous working fluid and a liquid working fluid. The working fluid in the gas state flows out from the gas outlet 117 og. The working fluid in a liquid state flows out from the liquid outlet 117ol.

  The working fluid in the liquid state is discharged from the gas-liquid separator 117 by the portion of the third circulation path 303 that extends from the liquid outlet 117ol to the sixth connection point p6. This portion can be referred to as a liquid discharge path 135. The upstream end of the liquid discharge path 135 is connected to the liquid outlet 117ol. The downstream end of the liquid discharge path 135 is connected to the sixth connection point p6. A fifth valve 145 appears in the liquid discharge path 135.

  The fifth valve 145 is a valve whose opening degree can be changed. By changing the opening degree of the fifth valve 145, the flow rate of the working fluid flowing through the liquid discharge path 135 can be adjusted. However, an electromagnetic on-off valve may be used as the fifth valve 145.

  According to the fifth valve 145, the discharge amount of the working fluid in a liquid state from the liquid outlet 117ol of the gas-liquid separator 117 can be controlled. The fifth valve 145 can be referred to as a liquid discharge control valve 145.

  In the present embodiment, the sixth connection point p6, which is the connection destination of the liquid discharge path 135, is in the portion between the third connection point p3 and the inlet of the condenser 113 in the first circulation path 201. In this way, it is difficult to hinder the flow of the working fluid flowing out from the internal space 104 of the first container 112d through the first outlet 105o. However, the sixth connection point p6 can be set at any part of the first circulation path 201 between the first outlet 105o and the inlet of the condenser 113. Further, the sixth connection point p6 can be set at any part of the bypass path 131 between the outlet of the second valve 142 and the third connection point p3.

  By opening the fifth valve 145, the working fluid can circulate through the third circulation path 303 based on the difference between the pressure of the working fluid at the outlet of the pump 115 and the pressure of the working fluid at the inlet of the condenser 113. .

  The opening degree of the fifth valve 145 is controlled such that the working fluid in the liquid state accumulated in the gas-liquid separator 117 is discharged. Specifically, the opening degree of the fifth valve 145 is increased under the condition that the working fluid in the liquid state increases. More specifically, the opening degree of the fifth valve 145 is increased as the detected temperature Tg of the third temperature sensor 153 is lower. The control device 150 is responsible for controlling the opening degree of the fifth valve 145.

  In the Rankine cycle device 300, a fifth circulation path 305 in which the working fluid flows is configured. In the fifth circulation path 305, the pump 115, the first connection point p1, the evaporator 111, the fifth connection point p5, the sixth valve 146, the third inlet 107i of the first container 112d, and the internal space 104. Then, the second outlet 106o and the condenser 113 appear in this order. Specifically, in the fifth circulation path 305, the pump 115, the first connection point p1, the evaporator 111, the fifth connection point p5, the sixth valve 146, the third inlet 107i, and the internal space 104 The second outlet 106o, the fourth valve 144, the fourth connection point p4, and the condenser 113 appear in this order.

  A working fluid in a gaseous state for preheating the internal space 104 is supplied to the internal space 104 by a portion of the fifth circulation path 305 extending from the fifth connection point p5 to the third inlet 107i. This portion can be referred to as a preheated gas supply path 136. The upstream end of the preheating gas supply path 136 is connected to the fifth connection point p5. The downstream end of the preheating gas supply path 136 is connected to the third inlet 107i. A sixth valve 146 appears in the preheating gas supply path 136.

  The sixth valve 146 is a valve whose opening degree can be changed. By changing the opening degree of the sixth valve 146, the flow rate of the working fluid flowing through the preheating gas supply path 136 can be adjusted. However, an electromagnetic on-off valve may be used as the sixth valve 146.

  According to the sixth valve 146, the amount of the preheating gas working fluid supplied to the internal space 104 can be controlled. The sixth valve 146 may be referred to as a preheated gas supply control valve 146.

  In the present embodiment, the fifth connection point p5, which is the connection destination of the preheating gas supply path 136, is in the portion between the outlet of the evaporator 111 and the second connection point p2 in the first circulation path 201. However, the fifth connection point p5 can be set at any part of the first circulation path 201 between the outlet of the evaporator 111 and the first inlet 105i. Further, the fifth connection point p5 can be set at any part of the bypass path 131 between the second connection point p2 and the inlet of the second valve 142.

  By opening the sixth valve 146, the working fluid may circulate through the fifth circulation path 305 based on the difference between the pressure of the working fluid at the outlet of the evaporator 111 and the pressure of the working fluid at the inlet of the condenser 113. it can.

  When the expander 112 is not operated, the generator 116 does not generate heat. For this reason, the working fluid is not vaporized in the second container 112e. Suppose that a liquid working fluid is supplied from the second container 112e to the gas bearing 112c. When the expander 112 is operated in this state, there is a possibility that seizure occurs in the gas bearing 112c. Therefore, in the present embodiment, during the period from the start of operation of the expander 112 to the generation of the working fluid in the gaseous state in the second container 112e due to the heat of the generator 116, the first container 112d is passed through the preheating gas supply path 136. A working fluid in a gaseous state is supplied to the internal space 104. Thereby, the working fluid in a gaseous state can be supplied to the internal space 104 of the first container 112d even during this period. In the present embodiment, the opening degree of the third valve 143 is set to zero during this period.

  When time elapses from the start of power generation by the generator 116, heat is stably generated by the generator 116. With this heat, the working fluid in the second container 112e is heated, and the working fluid vaporized into the internal space 104 via the gas supply path 133 is stably supplied. After it is determined that such supply can be performed, the gas supply amount to the internal space 104 through the preheating gas supply path 136 is gradually reduced. In addition, after such a determination is made, the gas supply amount to the internal space 104 through the gas supply path 133 is gradually increased.

  The preheating gas supply path 136 and the sixth valve 146 are also applicable to the first and third embodiments.

  Also in the second embodiment, similarly to the first embodiment, the working fluid in a gaseous state is supplied to the internal space 104 of the first container 112d through the second circulation path 302. Further, in the second embodiment, a gas-liquid separator 117 is provided in preparation for a case where the amount of heat generated by the generator 116 is small. When the calorific value of the generator 116 is small, the working fluid flowing out from the second container 112e may not be in a completely gaseous state but may include a liquid. In such a case, the gas-liquid separator 117 separates the working fluid into a gaseous working fluid and a liquid working fluid. The working fluid in a gaseous state is supplied to the internal space 104 of the first container 112d. The working fluid in a liquid state is supplied to the condenser 113 via the liquid discharge path 135. The condenser 113 cools the working fluid together with the working fluid that has passed through the expansion mechanism 112a and the working fluid that has passed through the second container 112e.

  During a period when the power generation amount of the generator 116 is small, the heat generation amount of the generator 116 is small. In this period, the working fluid flowing out from the second container 112e can be in a gas-liquid two-phase state. Even in such a case, according to the gas-liquid separator 117 of the second embodiment, the working fluid in the gas-liquid two-phase state can be separated into the working fluid in the gas state and the working fluid in the liquid state. it can. And the working fluid in a gaseous state can be supplied to the gas bearing 112c.

(Embodiment 3)
Next, the Rankine cycle apparatus of Embodiment 3 is demonstrated. FIG. 3 is a configuration diagram of Rankine cycle apparatus 400 according to the third embodiment. In the third embodiment, description of portions common to the first embodiment may be omitted.

  Rankine cycle apparatus 400 includes a reheater 118. The reheater 118 includes a heat recovery path 118a and a heat application path 118b. In the reheater 118, the working fluid in the heat recovery path 118a exchanges heat with the working fluid in the heat application path 118b. A relatively low temperature working fluid flows into the heat recovery path 118a. A relatively high temperature working fluid flows into the heat application path 118b.

  In the Rankine cycle device 400, a first circulation path 401 is configured instead of the first circulation path 201. The first circulation path 401 is a path through which the working fluid flows. In the first circulation path 401, the pump 115, the first connection point p1, the heat recovery path 118a, the evaporator 111, the first inlet 105i, the expansion mechanism 112a, the first outlet 105o, and the heat application path 118b. And the condenser 113 appear in this order. Specifically, in the first circulation path 401, the pump 115, the first connection point p1, the heat recovery path 118a, the evaporator 111, the second temperature sensor 152, the second connection point p2, and the first connection point p1 The inlet 105i, the expansion mechanism 112a, the first outlet 105o, the third connection point p3, the fourth connection point p4, the heat application path 118b, the condenser 113, and the first temperature sensor 151 are arranged in this order. appear.

  In the Rankine cycle device 400, a second circulation path 402 is configured instead of the second circulation path 202. The second circulation path 402 is a path through which the working fluid flows. In the second circulation path 402, the pump 115, the first connection point p1, the second container 112e, the second inlet 106i, the internal space 104, the second outlet 106o, the heat application path 118b, and the condenser 113 are provided. And appear in this order. Specifically, in the second circulation path 402, the pump 115, the first connection point p1, the second container 112e, the third valve 143, the heater 119, the third temperature sensor 153, and the second inlet 106i. The internal space 104, the second outlet 106o, the fourth valve 144, the fourth connection point p4, the heat application path 118b, and the condenser 113 appear in this order.

  In the present embodiment, the reheater 118 is a so-called internal heat exchanger that performs heat exchange between working fluids at different points in the first circulation path 401. As the reheater 118, for example, a plate heat exchanger can be used.

  In the present embodiment, the fourth connection point p4, which is the connection destination of the gas discharge path 134, is in the portion of the first circulation path 401 between the third connection point p3 and the inlet of the heat application path 118b. In this way, the working fluid flowing out from the internal space 104 of the first container 112d through the second outlet 106o is supplied to the heat applying path 118b. The working fluid and the working fluid in the heat recovery path 118a can exchange heat. In this way, it is difficult to hinder the flow of the working fluid flowing out from the internal space 104 of the first container 112d through the first outlet 105o. However, the fourth connection point p4 can be set at any part of the first circulation path 401 between the first outlet 105o and the inlet of the heat application path 118b. Further, the fourth connection point p4 can be set at any part of the bypass path 131 between the outlet of the second valve 142 and the third connection point p3.

  As described above, in the present embodiment, the working fluid heated in the second container 112e flows into the heat application path 118b of the reheater 118 via the internal space 104 of the first container 112d. In the reheater 118, heat is exchanged between the working fluid in the heat application path 118b and the working fluid in the heat recovery path 118a. By this heat exchange, the working fluid in the heat recovery path 118a is heated. The heated working fluid flows to the evaporator 111 and the expansion mechanism 112a. For this reason, the rotational power obtained by the expansion mechanism 112a can be increased by the amount of heat given to the working fluid in the heat recovery path 118a. Further, the amount of power generation in the generator 116 can be increased by this amount. Thus, according to this Embodiment, the heat of a generator can be contributed to rotation power increase and electric power generation amount increase.

  The reheater 118 can also be applied to the second and fourth embodiments.

(Embodiment 4)
Next, the Rankine cycle apparatus of Embodiment 4 is demonstrated. FIG. 4 is a configuration diagram of a Rankine cycle apparatus 500 according to the fourth embodiment. In the fourth embodiment, description of parts common to the second embodiment may be omitted.

  The Rankine cycle apparatus 500 includes a decompressor 147. The decompressor 147 appears in the cooling path 132.

  Instead of the second circulation path 302, a second circulation path 502 is configured. The second circulation path 502 is a path through which the working fluid flows. In the second circulation path 502, the pump 115, the first connection point p1, the decompressor 147, the second container 112e, the second inlet 106i, the internal space 104, the second outlet 106o, and the condenser 113 , Appear in this order. Specifically, in the second circulation path 502, the pump 115, the first connection point p1, the decompressor 147, the second container 112e, the inlet 117i, the gas outlet 117og, the third temperature sensor 153, The third valve 143, the second inlet 106i, the internal space 104, the second outlet 106o, the fourth valve 144, the fourth connection point p4, and the condenser 113 appear in this order.

  In the Rankine cycle device 500, a third circulation path 503 is configured instead of the third circulation path 303. The third circulation path 503 is a path through which the working fluid flows. In the third circulation path 503, the pump 115, the first connection point p1, the decompressor 147, the second container 112e, the inlet 117i of the gas-liquid separator 117, the liquid outlet 117ol of the gas-liquid separator 117, The condenser 113 appears in this order. Specifically, in the third circulation path 503, the pump 115, the first connection point p1, the decompressor 147, the second container 112e, the inlet 117i of the gas-liquid separator 117, and the gas-liquid separator 117 The liquid outlet 117ol, the fifth valve 145, the sixth connection point p6, and the condenser 113 appear in this order.

  The decompressor 147 can supply the decompressed working fluid to the second container 112e. Examples of the pressure reducer 147 include a pressure reducing valve and a capillary tube. When a pressure reducing valve is used as the pressure reducing device 147, the amount of pressure reduction can be adjusted by changing the opening of the pressure reducing valve.

  The operation of the decompressor 147 will be described with reference to the Mollier diagram of FIG. FIG. 5 shows the difference between the case with and without the pressure reducer 147. The horizontal axis in FIG. 5 indicates the enthalpy h. The vertical axis in FIG.

In FIG. 5, a point A3 represents the state of the working fluid at the inlet of the pump 115. Point B1 represents the state of the working fluid at the outlet of the pump 115. As shown in FIG. 5, the pressure of the working fluid is increased from the pressure P ₃ to the pressure P ₁ by the pump 115.

When the decompressor 147 is not provided, the working fluid having the pressure P ₁ is supplied to the second container 112e. Here, it is assumed that the heat quantity Q = h _C −h _B is given from the generator 116 to the working fluid in the second container 112e. Point C1 represents the state of the working fluid after the amount of heat Q is given. Point C1 is in the region to the left of the saturated liquid line. This means that the working fluid is not vaporized in the second container 112e. That is, this means that the working fluid at the outlet of the second container 112e is maintained in a liquid state.

In order to change the working fluid in the state of the point C <b> 1 to a gas state, it is conceivable to reduce the opening degrees of the third valve 143, the fourth valve 144, and the fifth valve 145. In this way, the flow rate of the working fluid in the cooling path 132 is reduced. As the flow rate of the working fluid decreases, the amount of heating per unit mass of the working fluid in the second container 112e by the generator 116 increases. And the rise of the temperature of a working fluid becomes large. However, in this case, the working fluid does not enter a gaseous state until the temperature of the working fluid reaches T ₁ or more. Therefore, until the temperature Tg is above T _1, it is impossible to supply the working fluid in a gaseous state to the first container 112d.

In contrast, in the present embodiment, the pressure of the working fluid flowing through the cooling path 132 can be reduced from P ₁ to P ₂ by the pressure reducer 147. Point B2 in FIG. 5 represents the state of the working fluid after the pressure reduction. The working fluid having the pressure P ₂ obtained by this decompression is supplied to the second container 112e. It is assumed that the amount of heat Q = h _C −h _B is given from the generator 116 to the working fluid in the second container 112e. Point C2 represents the state of the working fluid after the amount of heat Q is given. The point C2 is in the gas-liquid two-phase region sandwiched between the saturated liquid line and the saturated air line. This means that the working fluid at the outlet of the second container 112e is in a gas-liquid two-phase state. The gas-liquid two-phase working fluid includes a gas-state working fluid indicated by a point D2 and a liquid-state working fluid indicated by a point D2 ′. The working fluid in the gaseous state at the point D2 can be extracted by the gas-liquid separator 117.

  As understood from the above description, when the pressure reducer 147 is used, the working fluid can be vaporized in the second container 112e even when the temperature of the working fluid at the outlet of the second container 112e is relatively low. it can. For this reason, even when the amount of heat exchange with the generator 116 and the working fluid in the second container 112e is relatively small, the working fluid in a gaseous state can be supplied to the gas bearing 112c.

  As described above, according to the decompressor 147 of the present embodiment, the decompressed working fluid can be supplied to the second container 112e. This decompression reduces the saturation temperature of the working fluid. Here, the saturation temperature refers to a temperature at which the working fluid starts to evaporate. Since the saturation temperature is lowered, the working fluid in the second container 112e can be vaporized even when the heat given from the generator 116 is relatively small. For this reason, according to this Embodiment, it is easy to vaporize the working fluid in the 2nd container 112e also in the period when the heat_generation | fever of the generator 116 is small and the temperature of the generator 116 is low.

  The decompressor 147 can also be applied to the first and third embodiments.

  Further, an on-off valve may be provided in the cooling path 132 together with the pressure reducer 147 or instead of the pressure reducer 147. Here, the on-off valve is a valve whose opening degree is selected from two of 0% and 100%. In this way, the flow of the working fluid in the second circulation path 502 can be blocked. The on-off valve can also be applied to the first to third embodiments.

  The Rankine cycle device according to the above embodiment can be applied to a heat recovery system that recovers heat with a working fluid and uses the recovered heat. This Rankine cycle device can also be applied to a cogeneration system such as a CHP system.

104 Internal space 104a, 104b Regions 105i, 106i, 107i, 117i Inlet 105o, 106o, 117og, 117ol Outlet 111 Evaporator 112 Expander 112a Expansion mechanism 112b Rotating shaft 112c Gas bearing 112d, 112e Container 112p Partition 113 Condenser 115 Pump 116 Generator 116a Rotor 116b Stator 117 Gas-liquid separator 118 Reheater 118a Heat recovery path 118b Heat application path 119 Heater 131, 132, 133, 134, 135, 136, 201, 202, 204, 302, 303, 305 , 401, 402, 502, 503 Route 141, 142, 143, 144, 145, 146 Valve 147 Pressure reducer 150 Controller 151, 152, 153 Temperature sensor 200, 300, 400, 50 0 Rankine cycle device p1, p2, p3, p4, p5, p6 Connection point

Claims (5)

Rankine cycle device,
The Rankine cycle device includes a pump, an evaporator, an expander, and a condenser.
The expander includes an expansion mechanism, a generator, a rotating shaft, a gas bearing, a first container, and a second container,
The generator includes a rotor and a stator,
The rotating shaft connects the expansion mechanism and the rotor,
The gas bearing supports the rotating shaft,
The first container includes an internal space, a first inlet, a first outlet, a second inlet, and a second outlet,
The internal space houses the expansion mechanism, the generator, the rotating shaft, and the gas bearing,
The second container is attached to the first container;
In the Rankine cycle device, a first circulation path through which the working fluid flows and a second circulation path through which the working fluid flows are configured,
In the first circulation path, the pump, the first connection point, the evaporator, the first inlet, the expansion mechanism, the first outlet, and the condenser appear in this order,
In the second circulation path, the pump, the first connection point, the second container, the second inlet, the internal space, the second outlet, and the condenser appear in this order. ,
The Rankine cycle apparatus in which the working fluid and the generator in the second container exchange heat. The Rankine cycle device includes a gas-liquid separator,
In the Rankine cycle device, a third circulation path through which the working fluid flows is configured,
In the second circulation path, the pump, the first connection point, the second container, the inlet of the gas-liquid separator, the gas outlet of the gas-liquid separator, the second inlet, An internal space, the second outlet, and the condenser appear in this order,
In the third circulation path, the pump, the first connection point, the second container, the inlet of the gas-liquid separator, the liquid outlet of the gas-liquid separator, and the condenser are: The Rankine cycle apparatus according to claim 1, which appears in this order. The Rankine cycle device includes a reheater,
The reheater includes a heat application path and a heat recovery path,
In the first circulation path, the pump, the first connection point, the heat recovery path, the evaporator, the first inlet, the expansion mechanism, the first outlet, and the heat application path. And the condenser appear in this order,
In the second circulation path, the pump, the first connection point, the second container, the second inlet, the internal space, the second outlet, the heat application path, and the condenser And appear in this order,
The Rankine cycle apparatus according to claim 1 or 2, wherein the working fluid in the heat application path and the working fluid in the heat recovery path exchange heat. The Rankine cycle device includes a decompressor,
In the second circulation path, the pump, the first connection point, the decompressor, the second container, the second inlet, the internal space, the second outlet, and the condenser The Rankine cycle apparatus according to any one of claims 1 to 3, wherein, appear in this order.   The Rankine cycle device has a cross section perpendicular to the axial direction of the rotating shaft, wherein the generator, a wall constituting the first container, and the second container are arranged in this order. Rankine cycle apparatus as described in any one of 1-4.

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