JP5797586B2 - Scroll type fluid machinery - Google Patents

Description

  The present invention relates to a scroll type fluid machine.

  2. Description of the Related Art Conventionally, a scroll type fluid machine that is an expander using a working medium as water is known. The output shaft is rotated by expanding water (hereinafter simply referred to as “steam”), which is a high-temperature and high-pressure gas phase, in an expansion chamber formed by a fixed scroll and an orbiting scroll.

  In such a scroll type fluid machine, in order to increase the output, a liquid film is interposed in the sliding portion of the expansion chamber to ensure sealing performance and lubricity, thereby preventing leakage of steam and frictional resistance of the sliding portion. Need to be reduced. On the other hand, when lubricating oil is mixed with steam in order to ensure the sealing performance and lubricity of the expansion chamber, a device for separating the lubricating oil from the steam discharged from the expansion chamber is required. Therefore, water that is a liquid phase generated by condensation in the process of expansion of saturated steam (hereinafter simply referred to as “water”) is used as a liquid film for ensuring sealing performance and lubricity. is there. For example, as described in Patent Document 1.

  However, the technique disclosed in Patent Document 1 performs sealing and lubrication with water generated by condensation caused by the process of expansion of steam in the expansion chamber. For this reason, sufficient sealability and lubricity cannot be ensured until the amount of water necessary for sealing and lubrication is generated. In particular, the steam immediately after being supplied to the expansion chamber may not have sufficient sealability and lubricity of the expansion chamber because there is almost no liquid phase. In other words, in the steam before expansion, it is difficult to interpose a liquid film in the sliding portion of the expansion chamber, so that the leakage of the steam and the frictional resistance of the sliding portion increase, and the output of the scroll fluid machine decreases. There was a problem that was a factor.

JP 2007-170288 A

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a scroll type fluid machine that uses water as a liquid phase of a working medium for sealing and lubricating an expansion chamber and increases output.

In claim 1, a scroll wrap projects from each end plate, and a fixed scroll and a movable scroll are arranged to face each other so as to mesh with each other, and the end plate of both scrolls and the scroll wrap A scroll-type fluid machine in which an expansion chamber is formed and steam is supplied to the expansion chamber, wherein the end plate of at least one of the movable scroll and the fixed scroll is provided with a steam heater, and the steam heater After being supplied and heating the steam in the expansion chamber, the steam in the steam heater is supplied to the expansion chamber, the steam heater forms a steam passage through which the steam passes, and the steam passage forms an orifice. And the middle of the steam passage is communicated with the orifice by a condensed water passage. It is those that.

According to a second aspect of the present invention, the steam passage is formed in a spiral shape in which the orifice is disposed at a central portion, and a steam supply port is disposed at an outer peripheral portion thereof.

According to a third aspect of the present invention, the steam passage is arranged at a position overlapping the scroll wrap of the end plate on which the steam heater is provided in a plan view of the end plate.

  As effects of the present invention, the following effects can be obtained.

  According to the first aspect of the present invention, the steam whose temperature has been lowered by expanding in the expansion chamber can be heated again by the high-temperature steam before being supplied to the expansion chamber. This increases the output of the scroll fluid machine.

  Moreover, since the vapor | steam supplied to the steam heater provided in at least one of a fixed scroll and a movable scroll can be supplied to an expansion chamber as it is, piping becomes easy.

Further , heat exchange is performed between the steam in the expansion chamber and the steam in the steam heater. Then, water generated by condensation in the steam heater can be sucked through the orifice and supplied into the expansion chamber. As a result, a liquid film is generated at the sliding portion in the expansion chamber immediately after the steam is supplied, and the sealing performance and lubricity of the expansion chamber are maintained.

According to the invention which concerns on Claim 2 , high temperature steam can be supplied from the outer edge part of the fixed scroll in which the steam temperature in an expansion chamber has fallen most. Thereby, the vapor | steam in an expansion chamber is heated efficiently, and an output increases.

According to the invention which concerns on Claim 3 , a scroll wrap can be heated preferentially. As a result, the scroll wrap acts as a heat radiating fin, and the steam in the expansion chamber is efficiently heated to increase the output.

Schematic which shows the structure of the Rankine cycle power generation system which is one Embodiment of this invention. (A) Sectional drawing of the scroll type fluid machine which is one Embodiment of this invention, (b) X arrow directional view in FIG. 2 (a) of a scroll type fluid machine similarly. The figure showing the phase change of the working medium (water) in the Rankine cycle power generation system which is one embodiment of the present invention. Schematic which shows the operation | movement aspect of the movable scroll in the scroll type fluid machine which concerns on one Embodiment of this invention. (A) An enlarged sectional view showing an operation mode of a steam heater of a scroll type fluid machine which is one embodiment of the present invention, (b) formed in an expansion chamber of the scroll type fluid machine which is one embodiment of the present invention. Schematic which shows a liquid film.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  First, the configuration of a Rankine cycle power generation system 100 including a scroll type fluid machine according to an embodiment of the present invention will be described with reference to FIG.

  Rankine cycle power generation system 100 drives generator 3 using a scroll-type fluid machine whose working medium is water (steam) as an expander. As shown in FIG. 1, the Rankine cycle power generation system 100 includes a scroll fluid machine 1, a generator 3, a steam generator 4, a working medium supply pump 6, and a condenser 8.

  The scroll fluid machine 1 is supplied with high-temperature and high-pressure steam as a working medium from a steam generator 4 through a working medium passage 2. The scroll fluid machine 1 generates electricity by driving the generator 3 using the supplied steam as a working medium. The steam generator 4 is supplied with water from a working medium supply pump 6 through a working medium passage 5. The working medium supply pump 6 sucks water generated by condensing the vapor by the condenser 8 through the working medium passage 7. The condenser 8 is supplied with steam discharged from the expansion chamber C of the scroll type fluid machine 1 through the working medium passage 9.

  In the Rankine cycle power generation system 100 having such a configuration, the scroll type fluid machine 1 drives the generator 3 by converting the energy of high-temperature and high-pressure steam generated by the steam generator 4 into rotational force. The steam discharged from the scroll type fluid machine 1 is condensed into water by the condenser 8 and then supplied again to the scroll type fluid machine 1 as high temperature and high pressure steam by the steam generator 4.

  Below, the structure of the scroll type fluid machine 1 which concerns on one Embodiment of this invention is demonstrated with reference to FIG. In addition, the white arrow in FIG. 2 has shown the flow direction of the vapor | steam which is a working fluid.

  The scroll type fluid machine 1 is an expander that converts high-temperature and high-pressure steam energy into rotational power and outputs it. As shown in FIG. 2A, the scroll fluid machine 1 mainly includes a fixed scroll 11, a movable scroll 14, and a crankshaft 15.

  The fixed scroll 11 is a member constituting the expansion chamber C. The fixed scroll 11 includes a mirror plate 11a and a spiral partition plate (hereinafter referred to as a fixed scroll wrap 11b) from the center of the mirror plate 11a formed on one side plate surface of the mirror plate 11a toward the end. The fixed scroll wrap 11b is formed based on a so-called involute curve. The fixed scroll 11 constitutes an expansion chamber C in combination with a movable scroll 14 described later. The fixed scroll 11 is fixed to a frame 16 that supports the crankshaft 15. A steam discharge port 11 c is provided at the outer edge of the fixed scroll 11. The condenser 8 is connected to the vapor discharge port 11 c through the working medium passage 9.

  The steam heater 12 heats the steam in the expansion chamber C. As shown in FIGS. 2A and 2B, the steam heater 12 is provided on the other side plate surface of the end plate 11 a of the fixed scroll 11. The steam heater 12 includes an end plate 11 a of the fixed scroll 11, a heater partition plate 12 a, and a heater cover 13. The heater partition plate 12a is formed in a spiral shape on the other side of the end plate 11a from the center of the end plate 11a toward the outer edge. The end face of the heater partition plate 12 a on the side opposite to the end plate is covered with a heater cover 13. Thus, the steam heater 12 includes a spiral steam passage 12b composed of the heater partition plate 12a and the heater cover 13. The heater partition plate 12a is formed between the fixed scroll wrap 11b and the fixed scroll wrap 11b in a plan view of the end plate 11a. That is, the steam passage 12b is disposed at a position overlapping the fixed scroll wrap 11b in plan view on the end plate 11a.

  The steam heater 12 is formed with an orifice 12c in such a manner that one end plate surface (expansion chamber C side) of the end plate of the fixed scroll 11 and the other side plate surface (steam heater 12 side) communicate with the end plate 11a at the center. Is done. That is, the steam heater 12 communicates with the expansion chamber C through the orifice 12c. The orifice 12c is configured to reduce the diameter from the steam heater 12 side toward the expansion chamber C side. In addition, the middle part of the orifice 12c is communicated with the middle part of the steam passage 12b through a condensed water passage 11d formed in the end plate 11a. That is, when the fluid (steam) flows from the steam heater 12 side to the expansion chamber C side through the orifice 12c, the pressure in the orifice 12c portion is lower than the pressure in the steam heater 12 due to the venturi effect.

  The condensed water passage 11 d is formed so as to go from the outer edge of the steam heater 12 (fixed scroll 11) to the orifice 12 c in the center of the steam heater 12. The condensed water passage 11d communicates with at least one of the adjacent steam passages 12b. That is, a plurality of communication holes are opened at predetermined intervals in the radial direction between the condensed water passage 11d and the steam passage 12b. In the steam heater 12, a steam supply port 12d is formed at the end of the steam passage 12b at the outer edge. A steam generator 4 is connected to the steam supply port 12d through the working medium passage 2.

  The movable scroll 14 is a member constituting the expansion chamber C. The movable scroll 14 includes a mirror plate 14a and a spiral partition plate (hereinafter referred to as a movable scroll wrap 14b) formed on one side plate surface of the mirror plate. The movable scroll wrap 14b is formed based on a so-called involute curve. The movable scroll 14 is disposed so as to face the fixed scroll 11. If it demonstrates in detail, the movable scroll 14 will be arrange | positioned in the state which the movable scroll wrap 14b facing the clearance gap between the fixed scroll wraps 11b was inserted, and was mutually combined. The fixed scroll 11 is disposed such that a minute gap is formed between one side plate surface of the end plate 14a of the movable scroll 14 and the end surface of the fixed scroll wrap 11b facing the fixed scroll 11. Similarly, the movable scroll 14 is arranged so that a minute gap is formed between one side plate surface of the end plate 11a of the fixed scroll 11 and the end surface of the movable scroll wrap 14b facing the movable scroll wrap 14b.

  The crankshaft 15 is a member having an eccentric shaft (hereinafter referred to as a pin portion 15a) formed at an end portion. Since the pin portion 15a is eccentric with respect to the crankshaft 15, the pin portion 15a is configured to revolve around the outer periphery of the crankshaft 15. The crankshaft 15 is rotatably supported by the frame 16. The pin portion 15 a supports the end plate 14 a of the movable scroll 14 via the bearing portion 17. Therefore, the pin portion 15 a revolves around the outer periphery of the crankshaft 15 as the movable scroll 14 turns. That is, the crankshaft 15 is rotated by the turning motion of the movable scroll 14.

  Next, the phase change of the working medium (water) in the Rankine cycle power generation system 100 will be described with reference to FIG.

  FIG. 3 is a TS diagram (temperature-entropy diagram) in the present embodiment. The arrows in the figure indicate the Rankine cycle of water or steam as the working medium.

  As shown in FIG. 3, the temperature T1 is the inlet temperature of the condenser 8, and the temperature T2 is the steam temperature. Point A1 is the state of the working medium at the inlet of the steam generator 4 (outlet of the condenser 8). Point A <b> 2 is a steam generation start point in the steam generator 4. Point A3 is the state of the working medium at the outlet of the steam generator 4 (supply port of the scroll type fluid machine 1). Point A4 is the state of the working medium at the vapor outlet 11c (inlet of the condenser 8) of the scroll type fluid machine 1.

  Between point A1 and point A2, the working medium exists as water which is a liquid phase and is heated and pressurized by the steam generator 4. And in the state of point A2, a working medium starts the phase change from water to the vapor | steam which is a gaseous phase.

  The working medium is further heated and pressurized by the steam generator 4 between the points A2 and A3. During this time, the working medium is a mixture of water that is a liquid phase and steam that is a gas phase. The working medium has completed the phase change to steam in the state of point A3. Between points A3 and A4, the working medium works (swivels the movable scroll 14) while expanding in the expansion chamber C of the scroll type fluid machine 1. Since the expansion of the working medium in the expansion chamber C is an approximate adiabatic expansion, the temperature of the working medium decreases. During this time, a part of the working medium condenses and starts a phase change from vapor that is a gas phase to water that is a liquid phase.

  Between point A4 and point A1, the working medium is cooled by the condenser 8 and condensed at a constant pressure. During this time, the working medium starts a phase change from vapor as a gas phase to water as a liquid phase. As a result, the phase change of the working medium into water that is a liquid phase in the state of the point A1 is completed.

  Next, the operation | movement aspect of the movable scroll 14 is demonstrated using FIG. Specifically, a mode in which the movable scroll 14 performs a turning motion by the supplied steam will be described. In addition, the arrow in a figure has shown the turning direction of the movable scroll 14. FIG. Moreover, the shaded portion in the figure indicates the supplied steam.

  FIG. 4A shows a state where steam is supplied to the expansion chamber C composed of the fixed scroll 11 and the movable scroll 14. Here, the expansion chamber C is a space formed by contacting the plate surfaces of the end plates 11a and 14a of the fixed scroll 11 and the movable scroll 14 and the side surfaces of the fixed scroll wrap 11b and the side surfaces of the movable scroll wrap 14b (steam Is a confined space). Steam is supplied to the expansion chamber C from the steam heater 12 through the orifice 12c.

  FIG. 4B shows a state in which the movable scroll 14 is turned from the state shown in FIG. 4A with respect to the fixed scroll 11. The movable scroll 14 is moved by the expansion of steam so that the position on the fixed scroll wrap 11b with which the movable scroll wrap 14b contacts is directed toward the outer edge of the fixed scroll 11 along the fixed scroll wrap 11b. That is, the movable scroll 14 is turned by a force that expands the steam supplied to the expansion chamber C and tries to expand the expansion chamber C. Thereby, the movable scroll 14 is turned around the rotation axis L. At this time, the temperature of the steam decreases with expansion. As the movable scroll 14 moves, the orifice 12c of the steam heater 12 communicating with the expansion chamber C is closed by the end surface of the movable scroll wrap 14b. That is, the expansion chamber C is sealed.

  FIG. 4C shows a state in which the movable scroll 14 is further turned from the state shown in FIG. 4B with respect to the fixed scroll 11. The movable scroll 14 is rotated by a force that further expands the steam supplied to the expansion chamber C and tries to expand the expansion chamber C. The expansion chamber C is continuously moved toward the outer edge while increasing its volume by the movement of the position on the fixed scroll wrap 11b with which the movable scroll wrap 14b is in contact. Thereby, the movable scroll 14 is further turned around the rotation axis L. At this time, the temperature of the steam further decreases as the steam expands. As the movable scroll 14 moves, a separate expansion chamber C is formed at the center of the fixed scroll 11. The separate expansion chamber C communicates with the steam heater 12 through the orifice 12c and is supplied with steam.

  FIG. 4D shows a state in which the movable scroll 14 is further turned from the state shown in FIG. 4C with respect to the fixed scroll 11. The movable scroll 14 is further swung by the expansion of the steam supplied to the expansion chamber C and the separate expansion chamber C. Thereby, the movable scroll 14 is further turned around the rotation axis L. At this time, the temperature of the steam further decreases as the steam expands. The expansion chamber C is further moved toward the outer edge portion and communicated with the steam discharge port 11 c of the fixed scroll 11. As a result, the steam supplied to the expansion chamber C is discharged to the outside of the scroll type fluid machine 1.

  As described above, the movable scroll 14 is rotated 360 ° by a force that expands the steam supplied to the expansion chamber C and tries to expand the expansion chamber C. Further, the crankshaft 15 is rotated 360 ° by the turning motion of the movable scroll 14. When the movable scroll 14 approaches the vicinity of a predetermined turning angle, the orifice 12c communicates with a separate expansion chamber C that appears in the central portion, and steam is supplied to the expansion chamber C. Thus, the crankshaft 15 is thus rotated by the continuous orbiting motion of the movable scroll 14. In other words, the scroll fluid machine 1 continuously obtains rotational power by repeating such an operation.

  Next, the operation | movement aspect of the steam heater 12 is demonstrated using FIG.2 and FIG.5.

  As shown in FIG. 2, in the steam heater 12, the steam generated by the steam generator 4 is supplied from the steam supply port 12 d to the steam path 12 b via the working medium path 2 (see FIG. 1). At this time, the steam heater 12 heats the fixed scroll wrap 11b with the heat of the steam passing through the steam passage 12b. Since the fixed scroll wrap 11b constitutes a part of the expansion chamber C, heat exchange with the steam in the expansion chamber C is performed. That is, the steam heater 12 supplies heat via the fixed scroll wrap 11b to the steam in the expansion chamber C whose temperature has decreased due to expansion. As a result, the temperature of the steam in the expansion chamber C rises again, and the pressure in the expansion chamber C rises accordingly. That is, the force of turning the steam movable scroll 14 increases.

  In addition, the steam heater 12 has the highest temperature at the outer edge where the steam supply port 12d is formed. On the other hand, the fixed scroll 11 has the lowest temperature at the outer edge where the steam outlet 11c is formed. In other words, the steam heater 12 is supplied with steam from the steam generator 4 from the vicinity of the expansion chamber C at the outer edge portion where the steam whose temperature has decreased most due to expansion is filled (see the white arrow in FIG. 2B). As a result, the steam in the expansion chamber C at the outer edge is heated by the high-temperature steam, and the pressure in the expansion chamber C increases accordingly. That is, the steam heater 12 can efficiently exchange heat with the steam in the expansion chamber C.

  On the other hand, the temperature of the steam in the steam passage 12b decreases due to heat exchange with the steam in the expansion chamber C. As a result, as shown in FIG. 5A, a part of the steam in the steam passage 12b is condensed in the process of passing through the steam passage 12b, and water W is generated. That is, the steam heater 12 has the same effect as the condenser 8 and changes a part of the steam from the gas phase to the liquid phase (refer to the point A1 to the point A1 in FIG. 3).

  The steam that has passed through the steam passage 12b is discharged into the expansion chamber C through the orifice 12c at the center (see the white arrow in FIG. 5A). At this time, the pressure in the orifice 12c portion becomes lower than the pressure in the steam heater 12 due to the venturi effect. Therefore, a flow is generated in the condensed water passage 11d communicating with the middle portion of the orifice 12c toward the orifice 12c having a low pressure. As a result, the water W generated in the steam passage 12b is sucked into the orifice 12c through the condensed water passage 11d (see the arrow in FIG. 5A). That is, the steam heater 12 discharges the vapor in the vapor phase and the water W in the liquid phase into the expansion chamber C in the orifice 12c.

  The water W discharged from the steam heater 12 is supplied into the expansion chamber C together with the steam. As a result, as shown in FIG. 5B, the expansion chamber C includes the plate surfaces of the end plates 11a and 14a of the fixed scroll 11 and the movable scroll 14, and the end surfaces of the fixed scroll wrap 11b and the movable scroll wrap 14b opposite to the plate surfaces. A liquid film F is generated in a minute gap formed between the two. Thereby, as for the expansion chamber C, a micro clearance gap is obstruct | occluded. Similarly, in the expansion chamber C, a liquid film F is generated on the contact surface between the side surface of the fixed scroll wrap 11b and the side surface of the movable scroll wrap 14b. As a result, in the expansion chamber C, a minute gap on the contact surface is closed and friction on the contact surface is suppressed. As a result, in the expansion chamber C, steam leakage and contact surface wear are reduced. That is, the expansion chamber C can ensure sealing performance and lubricity by the liquid film F interposed in the minute gap and the contact surface.

  The above is the description of the configuration of the scroll fluid machine 1 and the operation mode of the movable scroll 14 according to the present embodiment. Although the scroll type fluid machine 1 is configured such that one crankshaft 15 is rotated by the turning motion of the movable scroll 14, it is not limited to such a configuration. Further, the technical idea of the present invention is not limited to the application to the scroll type fluid machine 1 described above, but can be applied to the scroll type fluid machine 1 having other configurations.

  As described above, the fixed scroll 11 and the movable scroll 14 provided with the scroll wraps 11b and 14b projecting from the respective end plates 11a and 14a are arranged to face each other so as to engage the scroll wraps 11b and 14b. The scroll type fluid machine 1 in which an expansion chamber C is formed by the end plates 11a and 14a and the scroll wraps 11b and 14b, and steam is supplied to the expansion chamber C, and at least one end plate of the movable scroll 14 and the fixed scroll 11 The steam heater 12 is provided, and steam is supplied to the steam heater 12 to heat the steam in the expansion chamber C, and then the steam in the steam heater 12 is supplied to the expansion chamber C. By comprising in this way, the vapor | steam which temperature fell by expanding in the expansion chamber C can be heated again by the high temperature steam before being supplied to the expansion chamber C. Thereby, the output of the scroll type fluid machine 1 increases. Moreover, since the steam supplied to the steam heater 12 provided in at least one of the fixed scroll 11 and the movable scroll 14 can be supplied to the expansion chamber C as it is, piping becomes easy.

  Further, the steam heater 12 is formed with a steam passage 12b through which steam passes, the steam passage 12b communicates with the expansion chamber C through the orifice 12c, and an intermediate portion of the steam passage 12b is formed by the condensed water passage 11d. 12c is communicated. With this configuration, heat exchange is performed between the steam in the expansion chamber C and the steam in the steam heater 12. Then, the water W generated by condensation in the steam heater 12 can be sucked through the orifice 12c and supplied into the expansion chamber C. Thereby, the liquid film F is produced | generated in the sliding part in the expansion chamber C immediately after vapor | steam was supplied, and the sealing performance and lubricity of the expansion chamber C are maintained.

  The steam passage 12b is formed in a spiral shape with an orifice 12c disposed at the center, and a steam supply port 12d is disposed at the outer periphery thereof. By comprising in this way, high temperature steam can be supplied from the outer edge part of the fixed scroll 11 in which the steam temperature in the expansion chamber C is the lowest. Thereby, the vapor | steam in the expansion chamber C is heated efficiently, and an output increases.

  Further, the steam passage 12b is disposed at a position overlapping the scroll wrap 11b provided with the steam heater 12 in a plan view of the end plate 11a. By comprising in this way, a scroll wrap can be heated intensively. Thereby, the scroll wrap 11 serves as a heat radiating fin, the steam in the expansion chamber C is efficiently heated, and the output increases.

DESCRIPTION OF SYMBOLS 1 Scroll type fluid machine 11 Fixed scroll 12 Steam heater 11a End plate 11b Fixed scroll wrap 14 Movable scroll 14a End plate 14b Movable scroll lap C Expansion chamber

Claims (3)

Each end plate is provided with a scroll wrap protruding so that a fixed scroll and a movable scroll are opposed to each other so that the scroll wraps engage with each other, and the end plate and the scroll wrap of both scrolls form an expansion chamber, A scroll type fluid machine in which steam is supplied to the expansion chamber,
A steam heater is provided on the end plate of at least one of the movable scroll and the fixed scroll,
After steam is supplied to the steam heater to heat the steam in the expansion chamber, the steam in the steam heater is supplied to the expansion chamber ,
The steam heater has a steam passage through which steam passes, the steam passage communicates with the expansion chamber via an orifice, and a middle portion of the steam passage communicates with the orifice by a condensed water passage. Scroll type fluid machine. 2. The scroll fluid machine according to claim 1, wherein the steam passage is formed in a spiral shape in which the orifice is disposed at a central portion, and a steam supply port is disposed at an outer peripheral portion thereof . The scroll type fluid machine according to claim 2, wherein the steam passage is arranged at a position overlapping the scroll wrap of the end plate on which the steam heater is provided in a plan view of the end plate .

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