JP5119017B2 - Multistage compressor and refrigerator - Google Patents

Description

The present invention, multi-stage compressor with intermediate cooling, relates 及 beauty refrigerator.

  In a multistage compressor, intermediate stage cooling for cooling a compressed fluid flowing through a flow path between stages is known. Effective intermediate stage cooling leads to a reduction in compression power.

In the intermediate stage cooling, there is a system in which a liquid is directly supplied to a compressed fluid flowing through a flow path between stages (see, for example, Patent Document 1). In the intermediate stage cooling of the liquid supply type (direct supply type), when the supplied liquid is vaporized in the flow path between the stages, heat corresponding to latent heat of evaporation is taken away from the compressed fluid.
JP 2006-17116 A

  An object of this invention is to provide the multistage compressor and refrigerator which can cool a compressed fluid effectively using the liquid supply type intermediate stage cooling.

  According to an aspect of the present invention, there is an interstage duct through which a fluid flows, and a liquid holding body that is disposed in the interstage duct and holds a liquid, and the liquid holding at which a part of the liquid vaporizes the liquid. There is provided a multistage compressor including a body and a liquid supply unit that supplies the liquid to the liquid holding body.

  According to this aspect, the liquid from the liquid supply unit is held by the liquid holding body arranged in the interstage duct. When the liquid is vaporized on the surface of the liquid holder, heat corresponding to latent heat of evaporation is taken away from the compressed fluid flowing through the interstage duct, and the compressed fluid is effectively cooled.

  According to another aspect of the present invention, a refrigerator including the multistage compressor of the above aspect is provided.

  According to this aspect, the coefficient of performance (COP) can be improved by reducing the compression power.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic partial cross-sectional view of a two-stage centrifugal compressor 12. The compressor 12 includes a rotating shaft 20, first and second impellers 31 and 32 attached to the rotating shaft 20, a driving device 25 that drives the rotating shaft, and a casing 40. The casing 40 rotatably supports the rotary shaft 20 and surrounds the first and second impellers 31 and 32. In the present embodiment, the driving device 25 has a built-in type electric motor (built-in motor). The built-in motor is advantageous for making the compressor 12 compact. In other embodiments, the driving device 25 may have an electric motor different from the built-in motor, and may be disposed at the shaft end.

  In the present embodiment, the casing 40 includes an interstage duct 45 that guides the compressed fluid from the first impeller 31 to the second impeller 32, a discharge duct 47 that discharges the compressed fluid from the second impeller 32, and the like. A diffuser guide vane 42 is disposed in the interstage duct 45, and a diffuser guide vane 44 is disposed in the discharge duct 47. The diffuser guide vanes 42 and 44 are used for converting the velocity energy of the compressed fluid into pressure energy. A guide vane (suction guide vane) 43 may be disposed in the interstage duct 45.

  In the present embodiment, the compressor 12 includes an intermediate stage cooling system 60 that includes a liquid holder 70 disposed in the interstage duct 45 and a liquid supply unit 80 that supplies a liquid for cooling to the liquid holder 70. Prepare.

  FIG. 2 is a schematic cross-sectional view of the liquid holder 70. The liquid holding body 70 includes a plurality of passages 71 through which the compressed fluid passes, and a plurality of surface portions 72 respectively facing the passages 71. In the present embodiment, each surface portion 72 extends at least in the radial direction and the axial direction. Further, as will be described later, each surface portion 72 may have a contour having at least one of a bend and a curve.

  In the present embodiment, each passage 71 is a space surrounded by at least two surface portions 72. The coolant from the liquid supply unit 80 is supplied to each surface portion 72 and spreads over the entire surface portion 72. The liquid holding body 70 can hold the liquid over substantially the entire surface portion 72. A liquid film is formed on the surface of each surface portion 72. The compressed fluid flowing through the flow path in the interstage duct 45 flows through each passage 71 of the liquid holding body 70. The surface of the surface portion 72 of the liquid holding body 70 is in contact with the compressed fluid flowing through the passage 71. When the liquid is vaporized from the surface portion 72 of the liquid holding body 70, heat corresponding to latent heat of vaporization is taken away from the compressed fluid.

  In the present embodiment, the compressed fluid flows in the interstage duct 45, whereas the liquid holding body 70 holding the liquid is stationary. A part of the compressed fluid continuously moves along the surface of the surface portion 72 of the liquid holding body 70. That is, the compressed fluid existing on one position of the surface portion 72 of the liquid holding body 70 is continuously refreshed. This is advantageous for increasing the relative amount of contact between the coolant and the compressed fluid.

  On the other hand, in the conventional system in which the cooling liquid is diffused and discharged into the interstage duct, a part of the discharged liquid is carried to the compressed fluid (main flow). Around the mainstream droplet, heat exchange between the liquid and the gas becomes inactive from a certain point in time. Part of the liquid carried to the main stream collides with the wall of the duct or the next impeller. In the diffusion discharge method, it is difficult to exchange heat uniformly between the compressed fluid and the liquid in the entire main stream.

  In the present embodiment, the compressed fluid (main flow) flows through the plurality of passages 71. In each passage 71, almost the entire compressed fluid (main flow) can come into contact with the liquid in the liquid holding body 70. As will be described later, the passages 71 can be fluidly connected to each other. The configuration in which the plurality of passages 71 are intricate can uniformly form a favorable disturbance in the entire mainstream. Further, in the present embodiment, when the main flow reaches the saturated vapor pressure, the liquid holding body 70 does not vaporize, so that unnecessary droplets are prevented from being carried to the main flow. With the vaporization of the liquid at the surface portion 72 of the liquid holding body 70, the heat of the compressed fluid is deprived throughout the mainstream.

  Therefore, in the present embodiment, the compressed fluid can be effectively cooled using liquid supply type (direct type) intermediate stage cooling. Further, it is advantageous in terms of cost as compared with a method using a relatively expensive injector.

  Returning to FIG. 1, in the present embodiment, the liquid holding body 70 is disposed in the vicinity of the middle between the first impeller 31 and the second impeller 32 in the interstage duct 45. The position of the liquid holding body 70 in the axial direction of the compressor 12 may be relatively close to the first impeller 31 as shown in FIG. 3A and relatively close to the second impeller 32 as shown in FIG. 3B. Also good. In addition, as shown in FIG. 3C, a plurality of liquid holding bodies 70 that are separated from each other may be arranged in the interstage duct 45. In the present embodiment, the arrangement area of the liquid holding body 70 has a predetermined length in the axial direction of the compressor 12. In addition, the arrangement area of the liquid holding body 70 has the same length as the flow path area of the interstage duct 45 in the radial direction of the compressor 12. In another embodiment, the radial arrangement area of the liquid holding body 70 can be made smaller than the flow path area of the interstage duct 45.

  In the present embodiment, the flow path area (flow path cross section) of the interstage duct 45 has a substantially annular shape in the arrangement range of the liquid holding body 70. The overall silhouette of the liquid holder 70 projected along the axial direction of the compressor 12 has a substantially annular shape corresponding to the flow path area of the interstage duct 45. That is, the liquid holding body 70 has an annular silhouette that is substantially the same as or substantially similar to the flow channel area.

  In the present embodiment, the liquid holding body 70 is arranged over the entire flow path cross section of the interstage duct 45 because the liquid holding body 70 has substantially the same silhouette as the flow path area of the interstage duct 45. As a result, the entire compressed fluid (main stream) is cooled. As will be described later, the liquid holding body 70 is made of a material that is relatively easy to process. Therefore, the shape of the liquid holding body 70 can be set relatively easily according to the flow path shape of the interstage duct 45.

  4A, the flow path area of the interstage duct 45 expands along the mainstream flow direction. In this case, the liquid holding body 70 can have a circumferential shape 70 a along the radially inner wall of the interstage duct 45 and a circumferential shape 70 b along the radially outer wall of the interstage duct 45.

  In the other form shown in FIG. 4B, the liquid holding body 70 is disposed at the bent portion of the interstage duct 45. Also in this case, the liquid holding body 70 can have a circumferential shape 70 c along the radially inner wall of the interstage duct 45 and a circumferential shape 70 d along the radially outer wall of the interstage duct 45. .

  In FIG. 1, the compressed fluid enters the inside of the liquid holding body 70 through one end portion in the axial direction of the liquid holding body 70. In addition, the compressed fluid exits from the liquid holding body 70 through the other end of the liquid holding body 70 in the axial direction.

  5A, the liquid holding body 70 is disposed relatively near the first impeller 31. In the other form shown in FIG. In the arrangement range of the liquid holding body 70, the compressed fluid (main flow) flows substantially radially in the interstage duct 45. The liquid holding body 70 has an overall shape (silhouette) that is substantially the same as or substantially similar to the flow path area. Even in this case, the entire silhouette of the liquid holding body 70 projected along the axial direction of the compressor 12 has a substantially annular shape corresponding to the flow path area of the interstage duct 45. The compressed fluid enters the inside of the liquid holder 70 through the radially inner end of the liquid holder 70. Further, the compressed fluid exits from the liquid holding body 70 through the other end portion of the liquid holding body 70 radially outward.

  5B, the liquid holding body 70 is disposed relatively near the second impeller 32 (near the inlet of the second impeller 32). In the arrangement range of the liquid holding body 70, the compressed fluid (main flow) flows substantially radially in the interstage duct 45. The liquid holding body 70 has an overall shape (silhouette) that is substantially the same as or substantially similar to the flow path area. Even in this case, the entire silhouette of the liquid holding body 70 projected along the axial direction of the compressor 12 has a substantially annular shape corresponding to the flow path area of the interstage duct 45. The compressed fluid enters the inside of the liquid holding body 70 through the radially outer end of the liquid holding body 70. Further, the compressed fluid exits from the liquid holding body 70 via the other end portion inward in the radial direction of the liquid holding body 70.

  FIG. 5C shows a form in which the shaft of the first impeller 31 (see FIG. 1) is not disposed at the suction port center of the second impeller 32. The liquid holding body 70 is disposed relatively near the second impeller 32 (near the inlet of the second impeller 32). In the arrangement range of the liquid holding body 70, the compressed fluid (main flow) flows substantially radially in the interstage duct 45. The liquid holding body 70 has an overall shape (silhouette) that is substantially the same as or substantially similar to the flow path area. Even in this case, the entire silhouette of the liquid holding body 70 projected along the axial direction of the compressor 12 has a substantially annular shape corresponding to the flow path area of the interstage duct 45. The compressed fluid enters the inside of the liquid holding body 70 through the radially outer end of the liquid holding body 70. Further, the compressed fluid exits from the liquid holding body 70 via the other end portion inward in the radial direction of the liquid holding body 70.

  Alternatively or additionally, in another form shown in FIG. 5C, the liquid holding body 70 can be disposed relatively close to the second impeller 32, as shown in FIG. 5D. In the arrangement range of the liquid holder 70, the compressed fluid (main flow) flows in the interstage duct 45 substantially in the axial direction. The liquid holding body 70 has an overall shape (silhouette) that is substantially the same as or substantially similar to the flow path area. In this case, the entire silhouette of the liquid holding body 70 projected along the axial direction of the compressor 12 has a substantially annular shape, a column shape, or a disk shape corresponding to the flow path area of the interstage duct 45. The compressed fluid enters the inside (passage) of the liquid holding body 70 through one end portion in the axial direction of the liquid holding body 70. In addition, the compressed fluid exits from the liquid holding body 70 through the other end of the liquid holding body 70 in the axial direction.

  6, 7 </ b> A, and 7 </ b> B are diagrams schematically illustrating the configuration of the liquid holding body 70. In FIG. 6, the liquid holding body 70 has a configuration in which a plurality of plate members 75 are arranged. Each plate member 75 has a wavy outline and a wall (surface portion 72) extending substantially along the axial direction of at least the interstage duct 45. The passage 71 described above is formed between the two plate members 75.

  As shown in FIGS. 7 and 7B, the axis of each unit wave (for example, a concave or convex central axis) in one plate member 75 is parallel to each other, and is arranged in the same plane as the wave axis. The reference axis 100 is inclined at a predetermined angle. In the present embodiment, for example, the reference shaft 100 is the axial direction of the interstage duct 45 (generally coincides with the mainstream flow direction). The plurality of plate members 75 include a plurality of first members 76 having an axis having an inclination angle α1 with respect to the reference axis 100, and a plurality of second members 77 having an axis having an inclination angle α2, and are orthogonal to the plane. The first member 76 and the second member 77 are alternately and repeatedly stacked along the direction in which the first member 76 and the second member 77 overlap.

  In the present embodiment, for example, the contour axis of the first member 76 is inclined outward in the radial direction of the compressor 12 (see FIG. 1) with respect to the axial direction of the interstage duct 45 along the mainstream flow direction. . The contour axis of the second member 77 is inclined inward in the radial direction of the compressor 12 with respect to the axial direction of the interstage duct 45 along the flow direction of the main flow. The inclination angle α1 may be the same as or different from the angle α2. The inclination angles α1 and α2 can be set to 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, and 85 °, for example. The above numerical value is an example, and the present invention is not limited to this.

  In the present embodiment, the inclination angles α1 and α2 being 65 ° or less are advantageous for suppressing an increase in pressure loss. When the inclination angles α1 and α2 are 5 ° or more, it is advantageous for the occurrence of preferable disturbance in the mainstream. The inclination angles α1 and α2 can be optimized according to design conditions. In the example under a certain condition according to the present embodiment, when the inclination angles α1 and α2 are both around 30 °, it was most effective for cooling the mainstream.

  In the present embodiment, the plate member 75 has a wavy contour, thereby promoting turbulent flow and enlarging the heat transfer area. In addition, since the wave axis of the plate member 75 has an inclination with respect to the axial direction of the interstage duct 45, it is effective for reliable contact between the compressed fluid and the plate member 75 and promotion of turbulence.

  In the present embodiment, the contact portion between the adjacent first member 76 and second member 77 has a relatively small area. As described above, the wave axis of the first member 76 and the wave axis of the second member 77 intersect at a predetermined angle. Therefore, one small region (point region) at the top of the wave of the first member 76 is in contact with one small region (point region) at the bottom of the wave of the second member 77. The passage surrounded by one concave wall of the first member 76 is fluidly connected to a plurality of passages surrounded by the respective concave walls of the adjacent second member 77. A part of the main flow flowing through the passage surrounded by the unit concave wall of the first member 76 can enter each of the plurality of passages surrounded by the unit concave wall of the second member 77.

  In FIG. 6, in the liquid holding body 70 having such a configuration in which a plurality of passages are complicated, a large number of partial disturbances occur in the entire liquid holding body 70, and as a result, the compressed fluid and the plate member 75 are reliably connected. Contact and acceleration of turbulence are realized.

  The plane passing through the top of the wave of one plate member 75 is substantially parallel or non-parallel to that of the other plate member 75. In the present embodiment, as shown in FIG. 2, the plurality of plate members 75 each have an overall shape extending along the radial direction of the interstage duct 45, and are spaced apart from each other along the circumferential direction. Yes. The plurality of plate members 75 can be arranged in the interstage duct 45 after being configured integrally as one element in advance.

  Alternatively, as shown in FIGS. 8A and 8B, a plurality of components (blocks) each composed of a plurality of plate members 75 can be arranged in the interstage duct 45 in the circumferential direction and / or the axial direction. In FIG. 8A, the plurality of plate members 75 in the interstage duct 45 have an overall shape extending along the radial direction of the interstage duct 45. In FIG. 8B, in one block having a plurality of plate members 75, the plane passing through the top of the wave of one plate member 75 is substantially parallel to that of the other plate member 75.

  8C, the plurality of plate members 75 each have an overall shape extending along the circumferential direction of the interstage duct 45, and are spaced apart from each other along the radial direction. Also in this form, an integral configuration type element may be used, or a plurality of blocks may be combined.

  In other embodiments, as shown in FIGS. 9, 10, and 11, the plurality of plate members 75 can have contours other than wavy. In FIG. 9, the plurality of plate members 75 have a substantially linear outline. The liquid holding body 70 has a plurality of passages 71 having a slit-shaped channel cross section. 10 and 11, the plurality of plate members 75 have a plurality of bends. In FIG. 10, the liquid holding body 70 has a plurality of passages 71 having a substantially rhombic channel cross section. In FIG. 11, the liquid holding body 70 has a hexagonal lattice structure or a honeycomb structure, and has a substantially hexagonal channel cross section.

  In another embodiment, as shown in FIGS. 12 and 13, the liquid holding body 70 can be constituted by one member. In FIG. 12, the liquid holding body 70 has a porous member 75A having a relatively high opening ratio. In FIG. 13, the liquid holding body 70 includes a sheet-like porous member 75B that is repeatedly folded. The porous member 75B preferably has a relatively high opening ratio, and has, for example, a mesh shape or a lattice shape. It is also possible to arrange a plurality of porous members 75B along the mainstream flow direction.

  In the present embodiment, the liquid holding body 70 has a structure in which a capillary phenomenon works and is excellent in liquid absorption. In the present embodiment, the plate member 75 can be made of a fiber material. A structure made of a fiber material is excellent in at least liquid absorbency, moldability, and shape maintenance after molding.

  In the present embodiment, the plate member 75 can be made of a porous material having high liquid absorbency. In this embodiment, the board member 75 is comprised from a nonwoven fabric. The material is appropriately selected according to the use conditions of the plate member 75 and the like. For example, the plate member 75 may have a structure in which an inorganic fiber is used as a skeleton, and a filler and a binding material cover the skeleton while forming voids. Alternatively, the plate member 75 can have a structure in which inorganic fibers and organic fibers are used as a skeleton, and the skeleton is covered with a filler and a binder while forming voids. Examples of the material used for the plate member 75 include inorganic fibers, natural fibers, semi-synthetic fibers, synthetic fibers, or a combination of two or more thereof. The nonwoven fabric applied to the board member 75 can be comprised from the fiber which has a structure which has the unusual cross section excellent in liquid absorption. In a nonwoven fabric having a large number of cavities or voids, capillarity works remarkably. In addition, the fall of the rigidity of the nonwoven fabric at the time of contacting with a liquid is suppressed because the hygroscopicity of the fiber raw material surface is low.

  In another embodiment, the plate member 75 can be made of a material other than the nonwoven fabric. The plate member 75 can include a reinforcing member that supports the liquid absorbing member in addition to a member made of a material excellent in liquid absorbing property. For example, the plate member 75 can be composed of a fiber object other than the nonwoven fabric and a resin object that holds the fiber object.

  FIGS. 14, 15, 16, 17 </ b> A, and 17 </ b> B are schematic diagrams illustrating configuration examples of the liquid supply unit 80. In the present embodiment, the liquid supply unit 80 includes a liquid supply source 82 and a local supply mechanism 84 that locally supplies the liquid to the liquid holding body 70. If necessary, the liquid supply unit 80 may include other elements such as a pump and a control valve. When the capillary action works, the liquid spreads throughout the liquid holding body 70 having high liquid absorbency. The local supply mechanism 84 can employ various local supply methods such as a method of dropping a liquid toward the liquid holder 70 and a method of immersing the end of the liquid holder 70 in the liquid. It is also possible to combine a plurality of supply methods.

  In FIG. 14, the local supply mechanism 84 has a spray pipe 85 having a plurality of nozzles. For example, the sprinkling pipe 85 can spray liquid on one surface of the liquid holding body 70. In FIG. 15, the local supply mechanism 84 has a liquid storage part 86. The end of the liquid holding body 70 contacts the liquid stored in the liquid storage section 86.

  In FIG. 16, the local supply mechanism 84 includes a spray pipe 87A, a liquid holding auxiliary body 87B, and a drain pipe 87C. The spray pipe 87A sprays the liquid holding auxiliary body 87B. The liquid holding auxiliary body 87B has high liquid holding properties and forms a liquid film with the liquid holding body 70 in the interstage duct 45. The excess liquid is sent to the drain pipe 87C. The local supply mechanism 84 shown in FIG. 16 can be preferably applied particularly to a duct through which a fluid flows substantially in the axial direction.

  The local supply mechanism 84 shown in FIGS. 17A and 17B can be preferably applied particularly to a duct through which fluid flows in a generally radial direction. 17A and 17B, the local supply mechanism 84 includes a first spraying pipe 88A, a second spraying pipe 88B, and a liquid holding auxiliary body 89. The liquid holding auxiliary body 89 has a sheet shape and an annular shape, and is disposed between the inner wall of the interstage duct 45 and the liquid holding body 70. That is, the liquid holding auxiliary body 89 is disposed so as to abut on the end face in the axial direction of the liquid holding body 70 (side surface of the annular liquid holding body 70). In the direction of gravity, the first spray pipe 88A is disposed relatively upward, and the second spray pipe 88B is disposed relatively downward. At a relatively upper position, the first sprinkling pipe 88 </ b> A is disposed above the liquid holding body 70 (the outer peripheral surface of the liquid holding body 70) and sprays liquid to the liquid holding auxiliary body 89. At a relatively lower position, the second spraying pipe 88 </ b> B is disposed above the liquid holding body 70 (the inner peripheral surface of the liquid holding body 70), and sprays the liquid onto the liquid holding auxiliary body 89. The liquid holding auxiliary body 87B has high liquid holding properties, holds the liquid from the first and second spray pipes 88A and 88B, and forms a liquid film with the liquid holding body 70. When the capillary action works, the liquid spreads throughout the liquid holding body 70 having high liquid absorbency.

  In the present embodiment, the static pressure in the interstage duct 45 is lower than the atmospheric pressure. When this system is used as a heat pump, the static pressure in the interstage duct 45 is lower than the pressure in the condenser. By using the differential pressure, the suction of the liquid in the liquid supply unit 80 is promoted. That is, the liquid supply part 80 having liquid absorption is preferably applied to the cooling of the interstage duct 45 having a negative pressure (negative pressure).

  In the intermediate stage cooling system 60 described above, the present invention is such that even under a negative pressure, the liquid is vaporized from the liquid holding body 70 in an extremely close to ideal state, and the fluid in the interstage duct 45 can be effectively cooled. Confirmed by the people.

  FIG. 18 is a schematic diagram illustrating the refrigerator 10 including the compressor 12 described above. The refrigerator 10 includes an evaporator 11, a compressor 12, a condenser 13, and a control device 15.

  In general, the working fluid 5 of the refrigerator 10 includes various known media such as chlorofluorocarbons, ammonia, and hydrocarbons. In addition, water can be used as the working fluid 5. In the present embodiment, water is used as the working fluid 5. Additives may be added to water for the purpose of adjusting phase change conditions. When the working fluid 5 is water, a high compression ratio (for example, a compression ratio of about 8 or more) is required in the refrigerator (heat pump). By using a multistage compressor (two stages in FIG. 18) as the compressor 12, it is relatively small and can provide a high compression ratio.

  In the refrigerator 10, the temperature of the input medium 19 can be lowered using the phase change of the working fluid 5. That is, in the evaporator 11, the working fluid 5 evaporates by absorbing the heat of the input medium 19 (heat source outside the cycle). In the compressor 12, the gaseous working fluid 5 (water vapor) from the evaporator 11 is compressed. In the condenser 13, the working fluid 5 deprived of heat by a heat source (cold heat) outside the cycle is condensed. The liquid working fluid 5 exiting the condenser 13 is appropriately returned to the evaporator 11 via a flow control valve (pressure boundary) 188.

  In the present embodiment, the evaporator 11 is a shell and tube type. That is, the evaporator 11 includes a chamber 130, a pump 131, a heat exchange tube 132, a spray mechanism 133, and a mist separator (not shown).

  In the evaporator 11, the working fluid 5 stored in the chamber 130 is caused to flow by the pump 131, and the working fluid 5 circulates through a path including the chamber 130, the pump 131, and the spray mechanism 133. By the heat exchange with the input medium 19 (hot medium) flowing in the heat exchange tube 132, the working fluid 5 evaporates in the chamber 130, and the input medium 19 is cooled. The evaporated working fluid 5 (water vapor) is discharged from the chamber 130 through the outlet. The evaporator using the shell and tube method has an advantage that the pressure loss with respect to the flow of the evaporated working gas is small. In another embodiment, the evaporator 11 is configured such that the gaseous working fluid 5 and the liquid working fluid 5 are in direct contact with each other, and an indirect heat exchange between the input medium 19 and the liquid is performed in a heat exchanger provided outside. You may have a structure to do.

  In the present embodiment, the condenser 13 is also a shell and tube type. That is, the condenser 13 includes a chamber 210, a pump 211, a heat exchange tube 212, and a spray mechanism 213.

  In the condenser 13, the working fluid 5 is condensed in the chamber 210 by heat exchange with the cold medium outside the cycle flowing in the heat exchange tube 212. The condensed liquid working fluid 5 (water) is stored in the chamber 210. The working fluid 5 stored in the chamber 210 is caused to flow by the pump 211, and the working fluid 5 circulates through a path including the chamber 210, the pump 211, and the spray mechanism 213. The circulation channel and the pump can be omitted. The condensed working fluid 5 (water) is appropriately supplied from the chamber 210 to the evaporator 11 via a flow rate adjusting valve (pressure boundary) 188. The above pressure boundary may be realized by using other general methods in addition to the flow rate control valve. In another embodiment, the condenser 13 is configured such that the gaseous working fluid 5 and the liquid working fluid 5 are in direct contact with each other, and the indirect heat between the liquids is provided by a heat exchanger provided downstream of the discharge port of the pump 211. You may have a structure which performs exchange.

  In this embodiment, both the chamber 130 of the evaporator 11 and the chamber 210 of the condenser 13 are vacuum chambers, and the internal space of the chamber 130 and the chamber 210 is set to a negative pressure. In the present embodiment, the heat exchange tubes 132 and 212 are arranged in the chambers 130 and 210 in a single-stage or multi-stage layer along the axial direction (gravity direction) of the chambers 130 and 210. As a constituent member of the heat exchange tubes 132 and 212, a metal tube (for example, a copper tube or an aluminum tube) having a high thermal conductivity is preferably used.

  In the present embodiment, the compressor 12 includes the intermediate stage cooling system 60 described above. That is, the intermediate stage cooling system 60 includes a liquid holder 70 disposed in the interstage duct 45 and a liquid supply unit 80 that supplies the liquid to the liquid holder 70.

  In the present embodiment, the liquid supply unit 80 includes a liquid supply source 82 and a local supply mechanism 84 that locally supplies the liquid to the liquid holding body 70. In the present embodiment, the chamber 130 of the condenser 13 and the chamber 210 of the evaporator 11 serve as a liquid supply source (82). The local supply mechanism 84 includes a spray pipe 181, a first supply pipe 182, a second supply pipe 183, a first valve 184, a second valve 185, and a drain pipe 186.

  In FIG. 18, the spray pipe 181 supplies liquid (water) from the chamber 210 of the condenser 13 or the chamber 130 of the evaporator 11 to the liquid holding body 70. A liquid holding auxiliary body may be disposed between the spray pipe 181 and the liquid holding body 70 as shown in FIG. In FIG. 18, the liquid (water) held in the liquid holding body 70 is vaporized in the interstage duct 45, whereby heat corresponding to the latent heat of vaporization is taken from the working fluid 5, and the working fluid 5 is cooled. By the intermediate stage cooling, the compression efficiency of the compressor 12 is improved and the compression power is reduced.

  In FIG. 18, the first supply pipe 182 is a pipe branched from the circulation path of the spray mechanism 133 of the evaporator 11, and the chamber 130 of the evaporator 11 and the spray pipe 181 of the liquid supply unit 80 are fluidized. Connect. One end of the second supply pipe 183 is connected to the bottom of the chamber 210 of the condenser 13. The second supply pipe 183 fluidly connects the chamber 130 of the condenser 13 and the spray pipe 181 of the liquid supply unit 80. The first valve 184 is disposed on the first supply pipe 182, and the second valve 185 is disposed on the second supply pipe 183.

  When the pressure in the condenser 13 is equal to or higher than a predetermined value, the first valve 184 is closed and the second valve 185 is opened. The opening degree of the second valve 185 can be adjusted as necessary. Liquid can be discharged from the sprinkling pipe 181 using the pressure difference between the chamber 210 of the condenser 13 and the sprinkling pipe 181.

  When the pressure of the condenser 13 is less than a predetermined value, the first valve 184 is opened and the second valve 185 is closed. The opening degree of the first valve 184 can be adjusted as necessary. The liquid can be discharged from the sprinkling pipe 181 using the pressure of the pump 131 of the evaporator 11.

  In the local supply mechanism 84, the excess liquid flows into the drain pipe 186. The drain pipe 186 is provided with a flow rate adjusting valve 187, which serves as a pressure boundary and the liquid flowing into the drain pipe 186 is guided into the chamber 130 of the evaporator 11. In addition, you may implement | achieve said pressure boundary by methods other than a flow regulating valve.

  In the present embodiment, the liquid used for the intermediate stage cooling is a liquefied product (water) of the working fluid (compressed fluid). As a result, the occurrence of problems associated with the mixing of the two, such as the chemical reaction between the gas and the liquid to produce impurities, is suppressed.

  The positional relationship among the evaporator, the compressor, and the condenser in the refrigerator is not limited to the example in FIG.

  Further, the compressor is not limited to two stages. The number of stages of the compressor can be 3, 4, 5, 6, 7, 8, 9, or 10 or more.

  FIG. 19 is a schematic diagram showing a refrigerator 310 including a four-stage compressor 312. In the following description, the same components as those in the refrigerator 10 of FIG. 18 are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  In the refrigerator 310 shown in FIG. 19, the compressor 312 includes the rotary shaft 20, the drive device 25, the first impeller 31, the second impeller 32, the third impeller 33, the fourth impeller 34, and the casing 40.

  The casing 40 includes an inlet duct 41 that guides the compressed fluid from the chamber 130 of the evaporator 11 to the first impeller 31, an interstage duct 45 that guides the compressed fluid from the first impeller 31 to the second impeller 32, and the second impeller 32. The interstage duct 46 that guides the compressed fluid to the third impeller 33, the interstage duct 48 that guides the compressed fluid from the third impeller 33 to the fourth impeller 34, and the compressed fluid from the fourth impeller 34 to the chamber of the condenser 13. It has an outlet duct 49 leading to 210.

  The liquid holding bodies 70 of the intermediate stage cooling system 60 are disposed in the interstage ducts 45, 46, and 48, respectively. In the present embodiment, the local supply mechanism 84 of the liquid supply unit 80 includes the spray pipe 181, the first supply pipe 371, the second supply pipe 372, the third supply pipe 373, the fourth supply pipe 374, and the fifth supply pipe 375. A sixth supply pipe 376, a first valve 381, a second valve 382, a third valve 383, a fourth valve 384, a fifth valve 385, a sixth valve 386, a first drain pipe 391, a second drain pipe 392, and A third drain pipe 393 is provided.

  In the present embodiment, the liquid supply source 82 for the liquid holding body 70 in each interstage duct 45, 46, 48, 49 is the chamber 130 of the condenser 13 and the chamber 210 of the evaporator 11. Similarly to the embodiment of FIG. 18, the liquid (water) from the chamber 210 of the condenser 13 or the chamber 130 of the evaporator 11 is supplied to the liquid holding body 70 by the control of the valves 381 to 386.

  In each local supply mechanism 84, the excess liquid flows to the first to third drain pipes 391 to 393. The liquid that has flowed into the drain pipes 391 to 393 is guided into the chamber 130 of the evaporator 11 through flow rate adjusting valves 387 to 389 serving as pressure boundaries provided in the middle of each pipe. In addition, you may implement | achieve said pressure boundary by methods other than a flow regulating valve.

  Also in the present embodiment, the liquid (water) held in the liquid holding body 70 is vaporized in the interstage ducts 45, 46, 48, whereby heat corresponding to the latent heat of evaporation is taken from the working fluid 5, and the working fluid 5 is cooled. By the intermediate stage cooling, the compression efficiency of the compressor 12 is improved and the compression power is reduced.

  Each flow passage area (flow passage cross section) of the interstage ducts 45, 46, 48 has a substantially annular shape in the arrangement range of the liquid holding body 70. In the present embodiment, the flow passage cross-sectional area decreases in the order of the interstage duct 45, the interstage duct 46, and the interstage duct 48. The overall silhouette of the liquid holder 70 projected along the axial direction of the compressor 12 has a substantially annular shape corresponding to the flow path areas of the interstage ducts 45, 46, and 48. That is, the size of the corresponding liquid holding body 70 becomes smaller in the order of the interstage duct 45, the interstage duct 46, and the interstage duct 48.

  In the present embodiment, the liquid holding body 70 has substantially the same silhouette as the flow path area of the interstage ducts 45, 46, and 48, so that the entire flow path cross section of the interstage ducts 45, 46, and 48 is covered. A liquid holding body 70 is disposed. As a result, the entire compressed fluid (main stream) is cooled.

  In the trial calculation example, when the intermediate cooling of the liquid supply type (direct type) is applied to the two-stage compression, the COP is 4.896. As a comparative example, COP was 4.511 in the indirect intermediate stage cooling in which the refrigerant flows inside the tube disposed in the interstage duct. In the three-stage compression, when the turbine single-stage efficiency was the same as that of the second stage, the indirect COP was 4.366 and the direct COP was 4.947. In the case of three-stage compression, when the turbine single-stage efficiency was improved to three stages, the indirect COP was 4.617 and the direct COP was 5.244. The above numerical values are examples for understanding, and the present invention is not limited thereto.

  In addition, the compressor of this invention can also be applied to a heat pump. The heat pump is applied to an air conditioner having at least one function of cooling, heating, dehumidification, and humidification, for example. The heat pump also transfers heat to and from a heat source such as a cooling device (such as a heat sink), a heating device (such as a floor heating device), a hot water supply device, a refrigeration device, a dehydration device, a heat storage device, a snow melting device, or a drying device. It can be applied to various heat utilization devices (including plants and systems). By adopting a heat pump having high compression efficiency in a heat utilization device, the device can be made compact and energy efficiency can be improved. In addition, since the working medium is water, energy efficiency is improved and various environmental advantages are obtained.

  The numerical value used in the above description is an example, and the present invention is not limited to this.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention. The present invention is not limited by the above description, but only by the appended claims.

FIG. 1 is a schematic partial cross-sectional view of a two-stage centrifugal compressor. FIG. 2 is a schematic cross-sectional view of the liquid holder. FIG. 3A is a schematic diagram illustrating another example of the arrangement of the liquid holders. FIG. 3B is a schematic diagram illustrating another example of the arrangement of the liquid holders. FIG. 3C is a schematic diagram illustrating another example of the arrangement of the liquid holders. FIG. 4A is a schematic diagram illustrating another example of the liquid holding body. FIG. 4B is a schematic diagram illustrating another example of the liquid holding body. FIG. 5A is a schematic diagram illustrating another example of a liquid holding body. FIG. 5B is a schematic diagram illustrating another example of the liquid holding body. FIG. 5C is a schematic diagram illustrating another example of the liquid holding body. FIG. 5D is a schematic diagram illustrating another example of a liquid holding body. FIG. 6 is a schematic diagram showing the form of the liquid holder. FIG. 7A is a schematic diagram illustrating a form of a liquid holding body. FIG. 7B is a schematic diagram illustrating the form of the liquid holder. FIG. 8A is a schematic diagram illustrating another example of the liquid holding body. FIG. 8B is a schematic diagram illustrating another example of the liquid holding body. FIG. 8C is a schematic diagram illustrating another example of the liquid holding body. FIG. 9 is a schematic diagram showing another example of the liquid holding body. FIG. 10 is a schematic diagram illustrating another example of the liquid holding body. FIG. 11 is a schematic diagram illustrating another example of the liquid holder. FIG. 12 is a schematic diagram illustrating another example of the liquid holding body. FIG. 13 is a schematic diagram illustrating another example of the liquid holder. FIG. 14 is a schematic diagram illustrating an example of the configuration of the liquid supply unit. FIG. 15 is a schematic diagram illustrating a configuration example of the liquid supply unit. FIG. 16 is a schematic diagram illustrating a configuration example of the liquid supply unit. FIG. 17A is a schematic diagram illustrating a configuration example of a liquid supply unit. FIG. 17B is a schematic diagram illustrating a configuration example of a liquid supply unit. FIG. 18 is a schematic diagram showing a refrigerator including a two-stage compressor. FIG. 19 is a schematic diagram showing a refrigerator including a four-stage compressor.

Explanation of symbols

  5 ... Working fluid, 10, 310 ... Refrigerator, 11 ... Evaporator, 12, 312 ... Compressor, 13 ... Condenser, 31, 32, 33, 34 ... Impeller, 25 ... Drive device, 40 ... Casing, 45, 46, 48 ... Interstage duct, 60 ... Intermediate cooling system, 70 ... Liquid holding body, 71 ... Passage, 72 ... Face part, 75 ... Plate member, 76 ... First member, 77 ... Second member, 80 ... Liquid supply Part 82, liquid supply source, 84 ... local supply mechanism, 85 ... spraying pipe, 87B ... liquid holding auxiliary body.

Claims (16)

An interstage duct through which fluid flows;
A liquid holder that is disposed in the interstage duct having an annular channel area and holds a liquid; and the liquid holder that vaporizes the liquid on at least a part of a surface thereof;
A liquid supply section for supplying the liquid to the liquid holder;
Equipped with a,
The liquid holding body has a plurality of passages through which the fluid passes, and a plurality of surface portions respectively facing the plurality of passages and supplied with the liquid,
Wherein the plurality of surface portions, a multi-stage compressor, wherein Rukoto extend radially in a radial direction of said interstage duct. An interstage duct through which fluid flows;
A liquid holder that is disposed in the interstage duct having an annular channel area and holds a liquid; and the liquid holder that vaporizes the liquid on at least a part of a surface thereof;
A liquid supply section for supplying the liquid to the liquid holder;
With
The liquid supply unit has a local supply mechanism that locally supplies the liquid to the annular liquid holder,
The local supply mechanism is disposed above the outer peripheral surface of the liquid holding body in the direction of gravity, and a first spray pipe for spraying the liquid onto a liquid holding auxiliary body that abuts on an end surface in the axial direction of the liquid holding body. And a second spray pipe that is disposed below the inner peripheral surface of the liquid holding body in the direction of gravity and sprays the liquid onto the liquid holding auxiliary body . The multistage according to claim 2 , wherein the liquid holding body includes a plurality of passages through which the fluid passes, and a plurality of surface portions that respectively face the plurality of passages and are supplied with the liquid. Compressor. The multistage compressor according to claim 1, wherein the liquid supply unit includes a local supply mechanism that locally supplies the liquid to the liquid holding body. The multistage compressor according to any one of claims 1 to 4, wherein the liquid holding body has a silhouette that is substantially the same as or substantially similar to the flow path area. The multistage compressor according to any one of claims 1 to 5 , wherein at least a part of the liquid holder has liquid absorbency. The multistage compressor according to any one of claims 1 to 6 , wherein the liquid holder has a structure in which a capillary phenomenon works. The multistage compressor according to any one of claims 1 to 7 , wherein a static pressure in the interstage duct is lower than an atmospheric pressure. The multistage compressor according to any one of claims 1 to 8 , wherein at least a part of the liquid holder is made of a nonwoven fabric. The multistage compression according to any one of claims 1 to 9 , wherein the liquid holding body includes a plate member having at least a part of a shape substantially along an axial direction of the interstage duct. Machine. The multistage compressor according to claim 10 , wherein the plate member has a contour having at least one of a bend and a curve. The multistage compressor according to claim 11 , wherein the plate member includes a first member and a second member which are arranged adjacent to each other and each have the contour. At least one of the first axis of the outline of the first member and the second axis of the outline of the second member is inclined with respect to the axial direction of the interstage duct. The multistage compressor according to claim 12 . The multistage compressor according to claim 13 , wherein the first shaft and the second shaft intersect each other at a predetermined angle. An interstage duct through which fluid flows;
A liquid holder that is disposed in the interstage duct and holds a liquid; and the liquid holder that vaporizes the liquid on at least a part of a surface thereof;
A multistage compressor having a liquid supply section for supplying the liquid to the liquid holding body;
An evaporator,
A condenser,
With
The liquid supply unit includes a local supply mechanism that locally supplies the liquid to the liquid holding body,
The local supply mechanism is a spray pipe for supplying the liquid from the evaporator chamber or the condenser chamber to the liquid holder,
A first supply pipe fluidly connecting the chamber of the evaporator and the spray pipe;
A first valve disposed on the first supply pipe;
A second supply pipe fluidly connecting the condenser chamber and the sprinkling pipe;
A second valve disposed on the second supply pipe;
And the liquid is supplied from the spray pipe by adjusting the opening degree of the first valve and the second valve according to the pressure of the condenser . The refrigerator according to claim 15 , wherein the working medium is water.

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