Ejector

Abstract

To suppress the occurrence of abnormal noise due to the self-excited vibration of the tip side of an inner nozzle by the pressure of a working fluid flowing in a clearance flow passage between the tip side of an outer nozzle and the tip side of the inner nozzle, in an ejector in which the base end side of the inner nozzle is press-fitted and fixed to the base end side of the outer nozzle.SOLUTION: The ejector 1 ejects the working fluid supplied to each supply port 11,12 from the corresponding outer nozzle 21 and inner nozzle 22, generates a negative pressure in the negative pressure generation chamber 14 to suck the target fluid, and discharges the target fluid from the discharge port 16. A flow passage 23 for the working fluid is provided between both nozzles 21,22, and a flow passage 24 for the working fluid is provided in the inner nozzle 22. The outer nozzle 21 includes an inflow hole 29 through which the working fluid flows from the supply port 11 into the flow path 23. A base end side 22a of the inside nozzle 22 includes a press-in part 47 press-fitted and fixed to a base end side 21a of the outside nozzle 21. The 21a on the base end side of the outer nozzle 21 includes a press-fitted portion 48 to which the press-fitting portion 47 is press-fitted and fixed, and a part of the press-fitted portion 48 is adjacent to the inflow hole 29.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to an ejector configured to generate negative pressure by supplying a working fluid, and to suck in and cause a target fluid to flow by the action of the negative pressure. [Background technology]

[0002] A known example of this type of technology is an ejector described in Patent Document 1 (see below). FIG. 4 shows a cross-sectional view of a portion of this ejector. This ejector includes a main casing 70 and two nozzles 71 and 72 that inject a working fluid into the main casing 70. Each nozzle 71 and 72 receives a working fluid from a different supply port (a first supply port 73 and a second supply port 74) formed in the main casing 70. One of the two nozzles 71 and 72 is an outer nozzle 71, and the other is an inner nozzle 72 disposed within the outer nozzle 71. A gap is formed between the tip of the outer nozzle 71 and the tip of the inner nozzle 72, forming a first flow path 75 through which the working fluid flows. The inner nozzle 72 also serves as a second flow path 76 through which the working fluid flows. Each supply port 73 and 74 receives a working fluid from a different injector. Each injector is driven by duty control that alternately opens and closes its valve. The working fluid supplied to each supply port 73, 74 flows through the corresponding flow paths 75, 76 and is sprayed from the corresponding nozzles 71, 72. This spraying of the working fluid generates negative pressure in the negative pressure generating chamber 77. This negative pressure causes the target fluid to be sucked into the negative pressure generating chamber 77 from the target fluid supply port 78. The target fluid then flows together with the working fluid to the diffuser and is discharged from the discharge port. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-56355 Summary of the Invention [Problem to be solved by the invention]

[0004] In the ejector described in Patent Document 1, a large diameter portion 72a on the base end side of the inner nozzle 72 is press-fitted and fixed into a large diameter portion 71a on the base end side of the outer nozzle 71. The press-fit position of the inner nozzle 72 relative to the outer nozzle 71 is farther away from the nozzle tip than a first supply port 73 corresponding to the outer nozzle 71. In addition, in a first flow path 75 between the two nozzles 71, 72, a small diameter portion 72b on the tip side of the inner nozzle 72 forms a free end relative to the press-fitted large diameter portion 72a. For this reason, when working fluid flows from the first supply port 73 to the first flow path 75, the pressure of the working fluid may vibrate the tip side (small diameter portion 72b) of the inner nozzle 72, raising concerns about the generation of abnormal noise due to self-excited vibration.

[0005] This disclosed technology has been made in consideration of the above circumstances, and its purpose is to suppress vibration of the tip side of the inner nozzle due to the pressure of the working fluid flowing through the gap flow path between the tip side of the outer nozzle and the tip side of the inner nozzle, in an ejector that is equipped with an outer nozzle and an inner nozzle that inject working fluid into a negative pressure generating chamber, and in which the base end side of the inner nozzle is press-fitted and fixed into the base end side of the outer nozzle, thereby suppressing the generation of abnormal noise due to self-excited vibration. [Means for solving the problem]

[0006] In order to achieve the above object, the technology described in claim 1 comprises a main body casing, the main body casing including a first working fluid supply port and a second working fluid supply port for receiving a supply of working fluid, a target fluid supply port for receiving a supply of target fluid, a negative pressure generating chamber for generating negative pressure by the working fluid, a diffuser communicating with the negative pressure generating chamber and through which the working fluid and the target fluid flow, and one discharge port for discharging the working fluid and the target fluid that have flowed through the diffuser to the outside, an outer nozzle provided corresponding to the first working fluid supply port and having a tip portion disposed in the negative pressure generating chamber for injecting the working fluid, an inner nozzle provided corresponding to the second working fluid supply port and disposed within the outer nozzle for injecting the working fluid, a first working fluid flow path through which the working fluid supplied from the first working fluid supply port flows, and a second working fluid flow path through which the working fluid supplied from the second working fluid supply port flows, the outer periphery of the base end side is press-fitted and fixed to the inner periphery of the base end side of the outer nozzle, the tip side of the inner nozzle forms a free end relative to the pressed-in base end side, a first working fluid flow path is formed between the tip side of the outer nozzle and the tip side of the inner nozzle, and a second working fluid flow path is formed in the inner nozzle, and negative pressure is generated in the negative pressure generating chamber by working fluid supplied to each working fluid supply port and sprayed from each corresponding nozzle, the target fluid is sucked from the target fluid supply port into the negative pressure generating chamber by the negative pressure, and the target fluid flows together with the working fluid to a diffuser and is discharged from a discharge port; the outer nozzle further comprises an inlet hole through which the working fluid flows from the first working fluid supply port into the first working fluid flow path, and the base end side of the inner nozzle includes a press-fit portion press-fitted and fixed to the outer nozzle, and the base end side of the outer nozzle includes a press-fit portion into which the press-fit portion is press-fitted, and a part of the press-fit portion is adjacent to the inlet hole.

[0007] According to the configuration of the above technology, the working fluid supplied to the first working fluid supply port flows through the first working fluid flow path to the outer nozzle, is injected from its tip into the negative pressure generating chamber, flows through the diffuser, and is discharged from the discharge port. The working fluid supplied to the second working fluid supply port flows through the second working fluid flow path to the inner nozzle, is injected from its tip into the negative pressure generating chamber, flows through the diffuser, and is discharged from the discharge port. In the negative pressure generating chamber, negative pressure is generated by the injection of the working fluid, and the target fluid supplied to the target fluid supply port is drawn into the negative pressure generating chamber, flows through the diffuser together with the working fluid, and is discharged from the discharge port. Here, the outer nozzle further includes an inlet hole through which the working fluid flows from the first working fluid supply port into the first working fluid flow path. In addition, a portion of the press-fitted portion on the base end of the outer nozzle, into which the press-fitted portion on the base end of the inner nozzle is press-fitted and fixed, is adjacent to the inlet hole. Therefore, the position on the inner nozzle where the pressure of the working fluid flowing from the inlet into the first working fluid flow path acts is near the base end side, which has higher rigidity than the tip end side, making it less likely that vibrations due to the working fluid will occur at the operating position of the inner nozzle.

[0008] In order to achieve the above object, the technology described in claim 2 is the technology described in claim 1, wherein the flow path area of ​​the outlet of the inlet hole is larger than the flow path area of ​​the first working fluid flow path.

[0009] According to the configuration of the above technology, in addition to the effect of the technology described in claim 1, the flow path area of ​​the outlet of the inlet hole is not smaller than the flow path area of ​​the first working fluid flow path, and the flow rate of the working fluid flowing into the first working fluid flow path is not restricted. [Effects of the Invention]

[0010] According to the technology recited in claim 1, it is possible to suppress vibrations at the tip end side of the inner nozzle caused by the pressure of the working fluid flowing into the first working fluid channel, and it is possible to suppress the generation of abnormal noise due to self-excited vibrations.

[0011] According to the technology recited in claim 2, in addition to the effect of the technology recited in claim 1, it is possible to ensure a necessary flow rate of the working fluid flowing into the first working fluid channel. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 3 is a front cross-sectional view showing an ejector according to an embodiment. [Figure 2] FIG. 2 is an enlarged cross-sectional view showing the upstream portion of FIG. 1 according to one embodiment. [Figure 3] FIG. 2 is a cross-sectional view showing the outer nozzle and the inner nozzle before assembly in one embodiment. [Figure 4] FIG. 10 is a cross-sectional view showing a part of an ejector according to a conventional example. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of an ejector will be described in detail with reference to the drawings.

[0014] [Ejector configuration] FIG. 1 shows a front cross-sectional view of an ejector 1. This ejector 1 is used, for example, in a fuel cell system to supply hydrogen gas to a fuel cell. The ejector 1 shown in FIG. 1 is properly positioned upside down. However, the ejector 1 can also be positioned tilted relative to the horizontal position shown in FIG. 1. As shown in FIG. 1, the ejector 1 includes a tubular main casing 10 for carrying a working fluid and a target fluid. For example, in a fuel cell system, hydrogen gas corresponds to the working fluid, and hydrogen off-gas corresponds to the target fluid. The main casing 10 includes an upstream section 10a and a downstream section 10b. In FIG. 1, the upstream section 10a corresponds to approximately the right half of the main casing 10, and the downstream section 10b corresponds to approximately the left half of the main casing 10.

[0015] The upstream section 10a is provided with a first working fluid supply port 11 and a second working fluid supply port 12 that receive a supply of working fluid, a target fluid supply port 13 that receives a supply of target fluid, and a negative pressure generation chamber 14 that generates negative pressure by the working fluid. The upstream section 10a is provided with two coaxial nozzles 21 and 22 that inject the working fluid into the negative pressure generation chamber 14. The two nozzles 21 and 22 are provided corresponding to the first working fluid supply port 11 and the second working fluid supply port 12, respectively. The tip of each nozzle 21 and 22 is positioned corresponding to the negative pressure generation chamber 14.

[0016] The downstream portion 10b is provided with a diffuser 15 that communicates with the negative pressure generating chamber 14 and through which the working fluid and the target fluid flow, and a single discharge port 16 for discharging the working fluid and the target fluid that have flowed through the diffuser 15 to the outside.

[0017] The ejector 1 injects the working fluid supplied to the working fluid supply ports 11 and 12 from the nozzles 21 and 22, generating a negative pressure in the negative pressure generating chamber 14. The ejector 1 also uses the generated negative pressure to suck the target fluid from the target fluid supply port 13 into the negative pressure generating chamber 14. The target fluid then flows together with the working fluid to the diffuser 15 and is discharged from the discharge port 16 toward downstream equipment.

[0018] In this embodiment, the two nozzles 21, 22 include an outer nozzle 21 and an inner nozzle 22. In this embodiment, the outer nozzle 21 and the inner nozzle 22 are arranged so that their axes coincide with the axis of the diffuser 15. The outer nozzle 21 is provided corresponding to the first working fluid supply port 11 for injecting the working fluid. The tip of the outer nozzle 21 opens into the negative pressure generating chamber 14. The inner nozzle 22 is provided corresponding to the second working fluid supply port 12 for injecting the working fluid. The inner nozzle 22 is arranged inside the outer nozzle 21, and its tip opens into the negative pressure generating chamber 14.

[0019] The first working fluid supply port 11 and the second working fluid supply port 12 are arranged in the main casing 10 along the axial direction of the nozzles 21, 22. The first working fluid supply port 11 is arranged adjacent to the tip side of the nozzles 21, 22 relative to the second working fluid supply port 12. The second working fluid supply port 12 is arranged away from the nozzles 21, 22.

[0020] Figure 2 shows an enlarged cross-sectional view of the upstream portion 10a of Figure 1. As shown in Figures 1 and 2, a gap is formed between the outer nozzle 21 and the inner nozzle 22. This gap communicates with the first working fluid supply port 11 and serves as a first working fluid flow path 23 through which the working fluid supplied from the first working fluid supply port 11 flows. The outer nozzle 21 is formed with a plurality of inlet holes 29 that communicate with the first working fluid supply port 11 and through which the working fluid flows into the first working fluid flow path 23. The first working fluid flow path 23 has an annular cross section.

[0021] The inside of the inner nozzle 22 is connected to the second working fluid supply port 12 and forms a second working fluid flow path 24 through which the working fluid supplied from the second working fluid supply port 12 flows.

[0022] 1, the main casing 10 is substantially cylindrical, and its hollow 25 has a different inner diameter in the longitudinal direction. The hollow 25 in the downstream portion 10b includes the negative pressure generating chamber 14, the diffuser 15, and the discharge port 16.

[0023] As shown in FIGS. 1 and 2 , the hollow 25 of the upstream section 10a includes a nozzle accommodating section 27 and an assembly space 28 with an inner diameter larger than that of the nozzle accommodating section 27. The nozzle accommodating section 27 includes the negative pressure generating chamber 14 and accommodates the outer nozzle 21 and the inner nozzle 22. The assembly space 28 is an operating space for assembling the nozzles 21 and 22 into the nozzle accommodating section 27. After the nozzles 21 and 22 are assembled into the nozzle accommodating section 27, a plug 41 is installed in the assembly space 28 to close the space 28. The plug 41 has a bottomed cylindrical shape and a multi-step outer diameter. The plug 41, installed in the assembly space 28, is fastened to the main casing 10 with bolts 43. A communication passage 30 that connects the second working fluid passage 24 and the second working fluid supply port 12 is formed between the inner wall of the assembly space 28 and the plug 41. In addition, a spring 44 for pressing the outer nozzle 21 against the step of the nozzle accommodating portion 27 is provided in the assembly space 28 between the plug 41 and the base end of the outer nozzle 21 .

[0024] In this embodiment, the first working fluid flow path 23 between the outer nozzle 21 and the inner nozzle 22 has a larger flow path area than the second working fluid flow path 24 in the inner nozzle 22. The first working fluid flow path 23 communicates with the first working fluid supply port 11 via an inlet 29. A linear solenoid valve (LSV) 31 is provided in the main casing 10 in correspondence with the first working fluid supply port 11. An outlet 31a of the LSV 31 is provided so as to communicate with the first working fluid supply port 11. The working fluid is supplied to an inlet 31b of the LSV 31. The LSV 31 is a solenoid valve that can linearly adjust the flow rate of the working fluid in a range where the required flow rate is high. In this embodiment, the LSV 31 has a well-known configuration, so a detailed description of the configuration will be omitted.

[0025] The second working fluid supply port 12 communicates with the second working fluid flow path 24 via the communication flow path 30. The main casing 10 is provided with an injector 32 corresponding to the second working fluid supply port 12 for injecting working fluid into the supply port 12. An outlet 32a of the injector 32 is disposed so as to communicate with the second working fluid supply port 12. The working fluid is supplied to an inlet 32b of the injector 32. The injector 32 is an electromagnetic valve that is driven to alternately open and close by duty control in a region where the required flow rate is small. In other words, the injector 32 is an electromagnetic valve that can intermittently inject working fluid in a region where the required flow rate is small. In this embodiment, the injector 32 has a well-known configuration, and therefore a detailed description of the configuration will be omitted.

[0026] [About the shapes of the outer and inner nozzles] FIG. 3 shows a cross-sectional view of the outer nozzle 21 and the inner nozzle 22 before assembly. As shown in FIGS. 2 and 3, the outer nozzle 21 is cylindrical and includes a base end side 21a and a tip end side 21b. A flange 21c is formed at the open end of the base end side 21a. A converging portion 21d, whose outer diameter converges toward the open end, is formed at the tip end side 21b. A sealing member 45 is fitted in a circumferential groove 21e formed on the outer periphery of the tip end side 21b. An inlet hole 29 of the outer nozzle 21 is formed at the boundary between the base end side 21a and the tip end side 21b. The outer nozzle 21 has the same inner diameter at the base end side 21a and the tip end side 21b. However, the inner diameter of the tip end side 21b decreases toward the tip at the converging portion 21d.

[0027] As shown in Figures 2 and 3, the inner nozzle 22 is cylindrical and includes a base end side 22a and a tip end side 22b. The outer diameter of the inner nozzle 22 gradually decreases from the base end side 22a to the tip end side 22b. The base end side 22a includes a base end large diameter portion 22aa and a base end small diameter portion 22ab. A seal member 46 is fitted in a circumferential groove 22ac formed on the outer periphery of the base end large diameter portion 22aa. The tip end side 22b includes a tip end large diameter portion 22ba and a tip end small diameter portion 22bb. The outer diameter of a boundary portion 22ad between the base end small diameter portion 22ab and the tip end large diameter portion 22ba changes in a tapered shape. The outer diameter of a boundary portion 22bc between the tip end large diameter portion 22ba and the tip end small diameter portion 22bb also changes in a tapered shape. Like the outer diameter, the inner diameter of the inner nozzle 22 gradually decreases from the base end side 22a to the tip end side 22b. The difference in outer diameter and inner diameter between the base end large diameter portion 22aa and the base end small diameter portion 22ab is large, at least 2. However, the difference in outer diameter and inner diameter between the base end large diameter portion 22aa and the base end small diameter portion 22ab does not have to be 2 or more.

[0028] In this embodiment, as shown in Fig. 2, when the inner nozzle 22 is assembled to the outer nozzle 21, the outer periphery of the base end small diameter portion 22ab of the inner nozzle 22 is press-fitted and fixed into the inner periphery of the base end side 21a of the outer nozzle 21, and the entire outer periphery of this portion becomes a press-fit portion 47 (shown by a thick two-dot chain line in Fig. 3). In other words, the base end side 22a of the inner nozzle 22 includes the press-fit portion 47 press-fitted and fixed into the inner periphery of the base end side 21a of the outer nozzle 21. In addition, the entire inner periphery of the base end side 21a of the outer nozzle 21 includes a press-fitted portion 48 (shown by dots in Fig. 3) into which the press-fitted portion 47 is press-fitted and fixed. A part of this press-fitted portion 48 is adjacent to the inlet hole 29. That is, the press-fit portion 47 of the inner nozzle 22 being press-fitted and fixed into the press-fitted portion 48 of the outer nozzle 21 means that the outer periphery of the base end small diameter portion 22ab of the inner nozzle 22 is press-fitted at least up to the boundary 49 with the inlet hole 29 on the inner periphery of the base end side 21a of the outer nozzle 21. Note that the base end small diameter portion 22ab of the inner nozzle 22 may be press-fitted into the inner periphery of the base end side 21a of the outer nozzle 21 beyond the boundary 49 with the inlet hole 29.

[0029] Here, in order to prevent the outlet of the inlet hole 29 from being narrowed, the flow path area of ​​the outlet of the inlet hole 29 is made larger than the flow path area of ​​the first working fluid flow path 23.

[0030] [Ejector action and effects] According to the configuration of the ejector 1 of this embodiment described above, the working fluid supplied to the first working fluid supply port 11 flows through the outer nozzle 21 via the first working fluid flow path 23, is injected from its tip into the negative pressure generating chamber 14, flows through the diffuser 15, and is discharged from the discharge port 16. The working fluid supplied to the second working fluid supply port 12 flows through the inner nozzle 22 via the second working fluid flow path 24, is injected from its tip into the negative pressure generating chamber 14, flows through the diffuser 15, and is discharged from the discharge port 16. Negative pressure is generated in the negative pressure generating chamber 14 by this injection of the working fluid. This negative pressure causes the target fluid to be sucked from the target fluid supply port 13 into the negative pressure generating chamber 14. The target fluid then flows together with the working fluid to the diffuser 15 and is discharged from the discharge port 16.

[0031] Here, the outer nozzle 21 further includes an inlet hole 29 through which the working fluid flows from the first working fluid supply port 11 into the first working fluid flow path 23. A part of a press-fitted portion 48 on the base end side 21a of the outer nozzle 21, into which the press-fit portion 47 on the base end side 22a of the inner nozzle 22 is press-fitted and fixed, is adjacent to the inlet hole 29. Therefore, the position of the inner nozzle 22 on which the pressure of the working fluid flowing from the inlet hole 29 into the first working fluid flow path 23 acts (the portion directly hit by the working fluid) is near the base end side 22a, which has higher rigidity than the tip end side 22b. This makes it difficult for vibrations due to the working fluid to occur at the operating position of the inner nozzle 22. Therefore, vibrations of the tip end side 22b of the inner nozzle 22 due to the pressure of the working fluid flowing into the first working fluid flow path 23 can be suppressed, and noise due to self-excited vibration can be suppressed.

[0032] Furthermore, according to the configuration of this embodiment, the mass of the tip side 22b is reduced by gradually reducing the outer diameter of the tip side 22b of the inner nozzle 22 that is farther from the press-fit portion 47. This increases the natural frequency of the inner nozzle 22, making it possible to suppress the generation of abnormal noise due to self-excited vibration.

[0033] Furthermore, according to the configuration of this embodiment, the flow path area of ​​the outlet of the inlet hole 29 of the outer nozzle 21 is not smaller than the flow path area of ​​the first working fluid flow path 23, and the flow rate of the working fluid flowing into the first working fluid flow path 23 is not restricted. Therefore, the required flow rate of the working fluid flowing into the first working fluid flow path 23 can be ensured.

[0034] The disclosed technology is not limited to the above-described embodiment, and part of the configuration can be appropriately modified within the scope of the disclosed technology.

[0035] (1) In the above embodiment, the outer diameter of the tip end 22b of the inner nozzle 22 is gradually reduced. However, the outer diameter of the tip end 22b of the inner nozzle 22 may be tapered or may be straight and have a constant outer diameter.

[0036] (2) In the above embodiment, the LSV 31 is provided corresponding to the first working fluid supply port 11 formed in the main casing 10, and the injector 32 is provided corresponding to the second working fluid supply port 12. However, an injector may be provided corresponding to the first working fluid supply port formed in the main casing, and an LSV may be provided corresponding to the second working fluid supply port. Alternatively, an LSV may be provided corresponding to each of the first and second working fluid supply ports formed in the main casing, or an injector may be provided corresponding to each of the first and second working fluid supply ports. [Industrial Applicability]

[0037] The disclosed technology can be applied to, for example, a fuel cell system mounted on a vehicle such as a hydrogen automobile. [Explanation of symbols]

[0038] 1 Ejector 10 Main casing 11 First working fluid supply port 12 Second working fluid supply port 13 Target fluid supply port 14 Negative pressure generating chamber 15 Diffuser 16 Outlet 21 Outer nozzle 21a base end 21b Tip side 22 Inner nozzle 22a Base end 22b Tip side 23 First working fluid flow path 24 second working fluid flow path 29 Inflow hole 47 Press-fit section 48 Press-fit part

Claims

1. A main body casing is provided. The main body casing includes: a first working fluid supply port and a second working fluid supply port for receiving a supply of working fluid; a target fluid supply port for receiving a supply of the target fluid; a negative pressure generating chamber for generating negative pressure by the working fluid; a diffuser communicating with the negative pressure generating chamber and through which the working fluid and the target fluid flow; a discharge port for discharging the working fluid and the target fluid that have flowed through the diffuser to the outside; Including, an outer nozzle provided in correspondence with the first working fluid supply port, the tip of which is disposed in the negative pressure generating chamber, and which injects the working fluid; an inner nozzle provided corresponding to the second working fluid supply port, disposed within the outer nozzle, and configured to inject the working fluid; a first working fluid flow path through which the working fluid supplied from the first working fluid supply port flows; a second working fluid flow path through which the working fluid supplied from the second working fluid supply port flows; Equipped with a base end side of the inner nozzle is press-fitted and fixed into a base end side of the outer nozzle, and a tip end side of the inner nozzle forms a free end relative to the press-fitted and fixed base end side; the first working fluid flow path is formed between a tip side of the outer nozzle and the tip side of the inner nozzle, and the second working fluid flow path is formed within the inner nozzle; Negative pressure is generated in the negative pressure generating chamber by the working fluid supplied to each of the working fluid supply ports and sprayed from each of the corresponding nozzles, and the target fluid is sucked into the negative pressure generating chamber from the target fluid supply port by the negative pressure, and the target fluid flows into the diffuser together with the working fluid and is discharged from the discharge port. In the ejector configured as above, the outer nozzle further includes an inlet hole through which the working fluid flows from the first working fluid supply port into the first working fluid flow path, The base end side of the inner nozzle includes a press-fit portion that is press-fitted and fixed to the base end side of the outer nozzle, and the base end side of the outer nozzle includes a press-fitted portion into which the press-fitted portion is press-fitted, and a part of the press-fitted portion is adjacent to the inlet hole. An ejector characterized by:

2. 2. The ejector according to claim 1, The flow path area of ​​the outlet of the inlet hole is larger than the flow path area of ​​the first working fluid flow path. An ejector characterized by:

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