JP2017020941A - Dynamic characteristic measurement apparatus for centrifugal rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dynamic characteristic measurement apparatus for a centrifugal rotary machine for suppressing rise of temperature in a magnetic force generating device.SOLUTION: A dynamic characteristic measurement apparatus 20 for a centrifugal rotary machine 1 for compressing or pressure-feeding fluid with rotation of impellers 3 and 4 attached to a shaft end part of a rotation shaft 2 comprises: a magnetic force generating device 21 which oscillates the impellers 3 and 4 by magnetic force; and a cooling device 30 which cools the magnetic force generating device 21 by a cooling medium.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a dynamic characteristic measuring apparatus for a centrifugal rotating machine that compresses or pumps fluid by rotation of an impeller attached to an end of a rotating shaft.

  For example, in a centrifugal rotating machine such as a centrifugal turbo compressor, the rotor causes self-excited vibration due to the excitation force of the compressed fluid (compressed gas) acting on the rotor with the impeller attached to the rotating shaft, and compression You may have to stop the machine. Whether or not the rotor generates self-excited vibration is determined by the damping ratio of the rotor (shaft vibration system). If the damping ratio is a positive value, self-excited vibration does not occur. Is known to be stable.

  Therefore, in order to operate the centrifugal rotating machine stably, it is important to appropriately grasp the damping ratio of the rotor. Therefore, Patent Document 1 discloses a dynamic characteristic measuring device that includes a magnetic force generator that vibrates the impeller with a magnetic force, and calculates the dynamic characteristic of the rotor in a state where the impeller is vibrated with the magnetic force generator. . It is possible to evaluate the stability of the rotor by obtaining the damping ratio of the rotor using such a dynamic characteristic measuring device.

JP 2014-102117 A

  By the way, as the above-described magnetic force generator, an electromagnet in which a coil is wound around an iron core is used, but the electromagnet is generally resin-molded for insulation. For this reason, when the magnetism generator is heated to a high temperature due to the heat generation of the magnetism generator itself or the temperature rise of the fluid, the resin as the insulator is melted, and there is a possibility that the insulating portion is short-circuited. However, Patent Document 1 does not consider this point at all.

  This invention is made | formed in view of the said subject, and it aims at suppressing the temperature rise of a magnetic force generator in the dynamic characteristic measuring apparatus of a centrifugal rotary machine.

  In order to achieve the above object, the present invention provides a dynamic characteristic measuring apparatus for a centrifugal rotating machine that compresses or pumps fluid by rotation of an impeller attached to an end of a rotating shaft, and And a cooling device for cooling the magnetic force generator with a cooling medium.

  According to the present invention, since the cooling mechanism for cooling the magnetic generator with the cooling medium is provided, the temperature increase of the magnetic generator can be suppressed.

It is a schematic diagram which shows the turbo compressor and dynamic characteristic measuring apparatus of 1st Embodiment. It is a control block diagram which shows the structure of a dynamic characteristic measuring apparatus. It is a schematic diagram which shows the turbo compressor and dynamic characteristic measuring apparatus of 2nd Embodiment. It is a schematic diagram which shows the turbo compressor and dynamic characteristic measuring apparatus of 3rd Embodiment. The schematic diagram which shows the modification of arrangement | positioning of a magnetic generator. The schematic diagram which shows the modification of arrangement | positioning of a magnetic generator. The schematic diagram which shows the modification of arrangement | positioning of a magnetic generator. The schematic diagram which shows the modification of arrangement | positioning of a magnetic generator. The schematic diagram which shows the modification of arrangement | positioning of a magnetic generator.

  Embodiments of a dynamic characteristic measuring apparatus for a centrifugal rotating machine according to the present invention will be described below with reference to the drawings. In each of the following embodiments, the case where the centrifugal rotary machine is a centrifugal turbo compressor has been described. However, the dynamic characteristic measuring apparatus according to the present invention includes a centrifugal turbo pump, The present invention can be applied to a centrifugal rotating machine such as a blower.

[First Embodiment]
FIG. 1 is a schematic diagram illustrating a turbo compressor and a dynamic characteristic measuring apparatus according to the first embodiment. In order to avoid complication of the figure, in FIG. 1, some reference numerals are omitted for the same components (the same applies to FIGS. 3 and 4).

  The centrifugal turbo compressor 1 is configured by housing a rotor 5 having a rotating shaft 2 and impellers 3 and 4 attached to both ends of the rotating shaft 2 in a casing 6. Suction ports 7 and 8 are respectively provided outside the impellers 3 and 4 in the axial direction of the rotary shaft 2, and the impellers 3 and 4 rotate from the suction ports 7 and 8 to rotate the impellers 3 and 4. The fluid (gas) sucked in is compressed, and the compressed fluid (compressed gas) is sent out radially outward (see the thick arrow in FIG. 1).

  As will be described later, since the impellers 3 and 4 are vibrated by a magnetic force when determining the dynamic characteristics of the rotor 5, the material of the impellers 3 and 4 is a magnetic body on which a magnetic attractive force acts, or A good conductor that generates eddy current is desirable. Examples of the magnetic material include iron and stainless steel having magnetism, and examples of the good conductor include aluminum, an aluminum alloy, and copper.

  A gear 9 (pinion gear) is provided at the center in the axial direction of the rotary shaft 2, and the gear 9 is meshed with a large-diameter gear (not shown) having a larger diameter than the gear 9. The rotation of the large-diameter gear is transmitted to the rotating shaft 2 through the gear 9, and the rotor 5 including the rotating shaft 2 and the impellers 3 and 4 rotates. Bearings 10 that rotatably support the rotating shaft 2 are provided on both sides of the gear 9 in the axial direction of the rotating shaft 2. A seal 11 is provided between the bearing 10 and the impellers 3 and 4 in the axial direction of the rotating shaft 2 to prevent leakage of compressed fluid.

  In the turbo compressor 1 configured as described above, the rotor 5 may self-excited due to the excitation force of the compressed fluid acting on the rotor 5 and the turbo compressor 1 may have to be stopped. In order to avoid such a situation, dynamic characteristics such as a damping ratio of the rotor 5 are measured by the dynamic characteristic measuring device, and the rotor 5 is less likely to cause self-excited vibration in an assumed operating condition range. Design is done.

  FIG. 2 is a control block diagram showing the configuration of the dynamic characteristic measuring apparatus. As shown in FIGS. 1 and 2, the dynamic characteristic measuring device 20 includes a magnetic force generator 21 that vibrates the impellers 3 and 4 with a magnetic force, a moving device 22 that moves the magnetic force generator 21 in the axial direction, and an impeller. It has a displacement measuring device 23 that measures the displacement in the axial direction of three or four. In FIG. 2, two magnetic force generators 21, moving devices 22, and displacement measuring devices 23, each of which is provided by eight, are illustrated.

  The magnetic force generator 21 is, for example, a resin-molded electromagnet in which a coil is wound around an iron core, and is arranged so that the axial direction of the iron core is substantially parallel to the axial direction of the rotary shaft 2. The magnetic force generators 21 are provided at intervals of 90 degrees in the rotation direction of the rotary shaft 2 at positions facing the outer peripheral portion of the rear surfaces of the impellers 3 and 4 (surfaces opposite to the suction ports 7 and 8). That is, four magnetic force generators 21 are provided for each impeller 3 and 4.

  The moving device 22 is, for example, a stretchable piezoelectric element, and is attached to each magnetic force generator 21. The moving device 22 moves the magnetic force generator 21 in the axial direction in response to a command from the control device 25 (see FIG. 2), and changes the distance between the tip of the magnetic force generator 21 and the rear surfaces of the impellers 3 and 4. can do. The moving device 22 is not limited to a piezoelectric element, and other means such as a cylinder or an inchworm actuator may be employed.

  The displacement measuring device 23 is an eddy current displacement sensor, for example, and is attached to the casing 6. Similarly to the magnetic force generator 21, the displacement measuring device 23 is also provided at intervals of 90 degrees in the rotation direction of the rotary shaft 2. Each displacement measuring device 23 may be arranged at a position shifted by about 20 degrees in the rotation direction from each magnetic force generator 21, or may be arranged radially inside each magnetic force generator 21. The displacement measuring device 23 is not limited to the eddy current type, and other means such as an optical displacement sensor may be employed.

  As shown in FIG. 2, the dynamic characteristic measurement device 20 further controls the operation of the pair of vibration sensors 24 that detect the vibration of the rotating shaft 2 and output a vibration signal, and the magnetic force generator 21 and the moving device 22. And a control device 25. The pair of vibration sensors 24 are arranged at positions 90 degrees apart from each other in the rotation direction of the rotary shaft 2.

  Based on the vibration mode selected by the operator via the operation unit 26, the control device 25 outputs a vibration signal to each magnetic force generator 21 to drive each magnetic force generator 21. As a driving method of the magnetic generator 21, there are, for example, sweep excitation in which the excitation frequency is changed, or impulse excitation in which a shocking input is applied to the impellers 3 and 4. As the vibration mode, for example, various rigid body modes and bending modes described in Patent Document 1 can be selected.

  The control device 25 performs frequency analysis and mode analysis of the rotor 5 based on the vibration signal from the magnetic force generator 21 and the vibration signal from the vibration sensor 24, and calculates the dynamic characteristics of the rotor 5. The calculation result is displayed on the display unit 27. Examples of the dynamic characteristics of the rotor 5 obtained by the control device 25 include a change in the damping ratio with respect to the load of the turbo compressor 1 such as gas power and a change in the damping ratio with respect to the driving time of the turbo compressor 1. Then, based on the calculation result, the rotor 5 that does not easily cause self-excited vibration is designed.

  Here, when the turbo compressor 1 is in operation, a thrust load acts on the rotor 5 and the rotor 5 may be displaced in the axial direction. For this reason, the space | interval of the impellers 3 and 4 and the magnetic force generator 21 changes, and there exists a possibility that the front-end | tip of the magnetic force generator 21 may contact the back surface of the impellers 3 and 4 in the worst case. Then, since the dynamic characteristic of the rotor 5 cannot be measured appropriately, the control device 25 drives each moving device 22 according to the axial displacement of the impellers 3 and 4 measured by the displacement measuring device 23. By doing so, the space | interval between the impellers 3 and 4 and the magnetic force generator 21 is maintained in a predetermined range.

  By the way, if the magnetic force generator 21 is heated to a high temperature due to the heat generated by the magnetic force generator 21 itself or the temperature of the fluid, the resin in which the electromagnet is molded is melted, and there is a possibility that the insulating portion is short-circuited. Therefore, the dynamic characteristic measuring device 20 is provided with a cooling device 30 that cools the magnetic force generator 21 with a cooling medium.

  As shown in FIG. 1, the cooling device 30 includes a storage chamber 31 that stores the magnetic force generator 21 and the moving device 22, a refrigerant supply channel 32 that supplies a cooling medium to the storage chamber 31, and a cooling medium from the storage chamber 31. And a refrigerant discharge passage 33 for discharging the refrigerant. The storage chamber 31 is embedded in a portion of the casing 6 that faces the back of the impellers 3 and 4. The magnetic force generator 21 accommodated in the accommodating chamber 31 passes through the wall surface 31 a facing the impellers 3, 4 of the accommodating chamber 31, and the tip of the magnetic force generator 21 faces the back of the impellers 3, 4. Is exposed.

  The refrigerant supply channel 32 is configured by appropriately combining channels formed in the hose or the casing 6, for example, and has an upstream end connected to the suction ports 7 and 8 and a downstream end connected to the storage chamber 31. Has been. For this reason, a relatively low temperature fluid before being compressed by the impellers 3 and 4 is taken into the refrigerant supply flow path 32 at the suction ports 7 and 8, and this fluid is supplied to the storage chamber 31 as a cooling medium. Note that the upstream end of the refrigerant supply flow path 32 is sucked so that the fluid before compression is smoothly taken into the refrigerant supply flow path 32 and the cooling medium is efficiently supplied to the storage chamber 31 by the dynamic pressure of the fluid. It is preferable that the openings 7 and 8 face each other in the fluid flow direction.

  For example, the refrigerant discharge flow path 33 is configured by appropriately combining the flow paths formed in the hose and the casing 6, and the upstream end is connected to the storage chamber 31 and the downstream end is outside the turbo compressor 1. It is open to the atmosphere. For this reason, the cooling medium supplied from the refrigerant supply channel 32 to the storage chamber 31 cools the magnetic generator 21 and the moving device 22 in the storage chamber 31 and is then discharged into the atmosphere from the refrigerant discharge channel 33. . Note that it is not essential to open the downstream end of the refrigerant discharge passage 33 to the outside of the turbo compressor 1, and in the internal space of the turbo compressor 1, the space is lower in pressure than the pressure in the storage chamber 31. You may make it open.

  Here, the compressed fluid compressed by the impellers 3 and 4 has a high temperature and a high pressure. For this reason, the back space of the impellers 3 and 4 facing the storage chamber 31 is also high in pressure, and the storage chamber 31 is formed from the gap between the wall surface 31 a facing the impellers 3 and 4 of the storage chamber 31 and the magnetic force generator 21. Compressed fluid may flow into If it does so, it will become impossible to supply a cooling medium from the refrigerant | coolant supply flow path 32 to the storage chamber 31. FIG.

  In order to avoid such a problem, a seal member 34 is provided between the wall surface 31 a facing the impellers 3 and 4 of the storage chamber 31 and the magnetic force generator 21. The seal member 34 is configured by, for example, a lip seal, an O-ring, an oil seal, or the like that can perform a seal without hindering the movement of the magnetic force generator 21. By providing such a seal member 34, it is possible to prevent high-pressure compressed fluid from flowing into the storage chamber 31 from the back space of the impellers 3 and 4, and to supply the cooling medium to the storage chamber 31 satisfactorily. .

(effect)
As described above, in the present embodiment, since the cooling device 30 that cools the magnetic force generator 21 with the cooling medium is provided, an increase in the temperature of the magnetic force generator 21 can be suppressed.

  In the present embodiment, the cooling device 30 includes a storage chamber 31 that stores the magnetic force generator 21 and a refrigerant supply that supplies the fluid before being compressed or pumped by the impellers 3 and 4 to the storage chamber 31 as a cooling medium. The flow path 32, the wall surface 31a which opposes the impellers 3 and 4 of the storage chamber 31, and the sealing member 34 provided between the magnetic force generator 21 which penetrates the said wall surface 31a are comprised. For this reason, it is not necessary to separately provide a fluid supply source or a blower for supplying the cooling medium, and the power and cost for cooling can be suppressed. In addition, by providing the seal member 34, it is possible to prevent a high-pressure compressed fluid from flowing into the storage chamber 31 from the impellers 3 and 4 side, and to supply the cooling medium to the storage chamber 31 satisfactorily.

  In the present embodiment, a moving device 22 that moves the magnetic force generator 21 in the axial direction of the rotating shaft 2 is further provided, and the cooling device 30 is configured to cool the moving device 22 together with the magnetic force generator 21. ing. For this reason, the temperature rise of the moving device 22 can be suppressed, and by extension, the temperature rise of the magnetic force generator 21 to which the moving device 22 is attached can be more effectively suppressed.

[Second Embodiment]
FIG. 3 is a schematic diagram illustrating a turbo compressor and a dynamic characteristic measuring apparatus according to the second embodiment. In the following description, configurations common to the first embodiment (the same reference numerals are assigned) and effects achieved by the configurations are omitted, and differences from the first embodiment are mainly described.

  In the turbo compressor 1 of the second embodiment, the fluid is first compressed by the impeller 3 (hereinafter referred to as “first impeller 3”), and the fluid compressed by the first impeller 3 is compressed by the intercooler 12. And a fluid cooled by the intercooler 12 is compressed by an impeller 4 (hereinafter referred to as “second impeller 4”) (see a thick arrow in FIG. 3). . The intermediate cooler 12 is disposed on the downstream side of the first impeller 3 and the upstream side of the second impeller 4, and the fluid compressed by the first impeller 3 is temporarily cooled by the intermediate cooler 12. It becomes easier to recompress the fluid by the second impeller 4.

  The cooling device 30 of the second embodiment is configured to supply the fluid cooled by the intermediate cooler 12 to the storage chamber 31 as a cooling medium. That is, the upstream end of the refrigerant supply channel 35 is connected to a pipe between the intermediate cooler 12 and the second impeller 4, and the refrigerant supply channel 35 is a channel branched from the pipe. . The refrigerant supply channel 35 is provided with respect to the storage chamber 31A (the storage chamber 31A facing the first impeller 3) in which the magnetic force generator 21 that vibrates the first impeller 3 is stored. It is not provided for the storage chamber 31B facing the second impeller 4. The reason will be described later.

(effect)
In the present embodiment, the cooling device 30 supplies the accommodation chamber 31A in which the magnetic force generator 21 that vibrates the first impeller 3 is accommodated and the fluid cooled by the intermediate cooler 12 to the accommodation chamber 31A as a cooling medium. And a refrigerant supply flow path 35. Here, the pressure in the back space of the first impeller 3 facing the storage chamber 31A is compressed by the first impeller 3 due to the influence of the compressed fluid leaking to the low pressure side (in the axial direction from the seal 11). It is slightly lower than the fluid pressure. On the other hand, since the cooling medium supplied to the storage chamber 31 </ b> A is obtained by cooling the compressed fluid compressed by the first impeller 3, the pressure is higher than the pressure in the back space of the first impeller 3. For this reason, the fluid does not flow into the accommodation chamber 31A from the back space of the first impeller 3, and the seal member 34 used in the first embodiment can be dispensed with.

  The pressure in the back space of the second impeller 4 is higher than the pressure of the cooling medium before the second compression is performed because the second compression is performed by the second impeller 4. Therefore, a storage chamber 31B (a storage chamber 31B facing the second impeller 4) in which the magnetic force generator 21 that vibrates the second impeller 4 is stored using the fluid cooled by the intermediate cooler 12 as a cooling medium. Can not be supplied to. Therefore, in order to supply the cooling medium to the storage chamber 31B facing the second impeller 4, a third embodiment described below can be adopted. Or if the same sealing member 34 as 1st Embodiment is provided in the accommodation chamber 31B facing the 2nd impeller 4, the fluid cooled with the intercooler 12 will be supplied to the accommodation chamber 31B as a cooling medium. Is also possible.

[Third Embodiment]
FIG. 4 is a schematic diagram illustrating a turbo compressor and a dynamic characteristic measuring apparatus according to a third embodiment. In the following description, configurations common to the first embodiment and the second embodiment (the same reference numerals are assigned) and effects produced by the configurations are omitted, and the first embodiment and the second are mainly described. Differences from the embodiment will be described.

  As in the second embodiment, the turbo compressor 1 of the third embodiment first compresses the fluid by the impeller 3 (hereinafter referred to as “first impeller 3”) and compresses the fluid by the first impeller 3. The fluid thus cooled is cooled by the intermediate cooler 12, and the fluid cooled by the intermediate cooler 12 is compressed by the impeller 4 (hereinafter referred to as "second impeller 4"). (See thick arrow in FIG. 4).

  As described in the second embodiment, when the fluid cooled by the intermediate cooler 12 is used as a cooling medium, the cooling medium is accommodated in which the magnetic force generator 21 that vibrates the second impeller 4 is accommodated. It is difficult to supply to the chamber 31B (the accommodation chamber 31B facing the second impeller 4). Therefore, in the third embodiment, the compressed fluid that has been compressed for the second time by the second impeller 4 is cooled by heat exchange with the fluid cooled by the intermediate cooler 12, and this is used as a cooling medium for the storage chamber. It is comprised so that it may supply to 31B.

  The heat exchanger 13 performs heat exchange between the compressed fluid compressed by the second impeller 4 and the fluid cooled by the intermediate cooler 12 (fluid before being recompressed by the second impeller 4). Is called. The heat exchanger 13 is connected to a cooling fluid passage 37 for introducing the cooling fluid cooled by the intermediate cooler 12 and a compressed fluid passage 38 for introducing the compressed fluid compressed by the second impeller 4. ing. Then, heat exchange is performed in the heat exchanger 13, whereby the compressed fluid is cooled by the cooling fluid, and the cooled compressed fluid is supplied as a cooling medium to the accommodation chamber 31 </ b> B through the refrigerant supply channel 39. The cooling fluid used for cooling the compressed fluid may be discharged into the atmosphere, or may be returned to the suction ports 7 and 8 for reuse.

(effect)
In the present embodiment, the cooling device 30 includes a storage chamber 31 </ b> B in which a magnetic force generator 21 that vibrates the second impeller 4 and a fluid compressed or pumped by the second impeller 4. A heat exchanger 13 that cools by heat exchange with the fluid cooled by the fluid, and a refrigerant supply passage 39 that supplies the fluid cooled by the heat exchanger 13 to the storage chamber 31B as a cooling medium. The Here, the pressure in the back space of the second impeller 4 facing the storage chamber 31B is compressed by the second impeller 4 due to the influence of the compressed fluid leaking to the low pressure side (in the axial direction from the seal 11). It is slightly lower than the fluid pressure. On the other hand, since the cooling medium supplied to the storage chamber 31B is obtained by cooling the compressed fluid compressed by the second impeller 4, the pressure is higher than the pressure in the back space of the second impeller 4. For this reason, the fluid does not flow into the accommodation chamber 31B from the back space of the second impeller 4, and the seal member 34 used in the first embodiment can be dispensed with. Note that the fluid cooled by the heat exchanger 13 may be supplied as a cooling medium to the accommodation chamber 31 </ b> A facing the first impeller 3.

[Other Embodiments]
The present invention is not limited to the above embodiment, and the elements of the above embodiment can be appropriately combined or variously modified without departing from the spirit of the present invention.

  For example, in the second and third embodiments, the turbo compressor 1 that compresses fluid in two stages has been described. However, a plurality of turbo compressors 1 are provided in series, and the fluid is compressed in multiple stages of two or more stages. Also good. When the fluid is compressed in multiple stages, the third embodiment is applied to the cooling of the magnetic force generator 21 that vibrates the impeller for the final stage of compression, and the cooling of the magnetic force generator 21 other than that is applied. By applying 2nd Embodiment, the sealing member 34 becomes unnecessary and can complete the heat exchanger 13 with one.

  Moreover, in the said embodiment, in order to avoid the contact with the magnetic force generator 21 and the impellers 3 and 4 reliably, the moving apparatus 22 which moves the magnetic force generator 21 was provided. However, when the contact between the magnetic force generator 21 and the impellers 3 and 4 is not particularly problematic, the moving device 22 can be omitted.

  Moreover, in the said embodiment, although the refrigerant | coolant discharge flow path 33 shall be open | released by the atmosphere outside the turbo compressor 1, the refrigerant | coolant discharge flow path 33 is made into the suction side (suction inlets 7 and 8 of the impellers 3 and 4). ) May be connected. By doing so, the fluid can be effectively reused, and the operation efficiency of the turbo compressor 1 can be improved. Further, since the fluid is not discharged into the atmosphere, it is possible to use a fluid (for example, nitrogen or carbon monoxide) that is not preferable to be discharged into the atmosphere for the turbo compressor 1.

  When the fluid is taken in from the suction ports 7 and 8 and used as a cooling medium as in the first embodiment, the refrigerant discharge channel 33 is the refrigerant supply channel in the fluid flow direction at the suction ports 7 and 8. It is preferable that it is located downstream from the upstream end of 32. By doing so, it is possible to avoid the cooling medium whose temperature has been increased by cooling the magnetic force generator 21 being taken into the refrigerant supply channel 32 again as the cooling medium.

  Moreover, when connecting the refrigerant | coolant discharge flow path 33 to the suction side of the impellers 3 and 4, More preferably, the refrigerant | coolant discharge flow path 33 is the impeller 3 which the magnetic force generator 21 cooled by the cooling device 30 vibrates. 4 may be connected to the suction side. That is, the downstream end of the refrigerant discharge passage 33 is connected to the suction side (suction port 7) of the impeller 3 in the second embodiment, and to the suction side (suction port 8) of the impeller 4 in the third embodiment. Is preferred. By carrying out like this, compression power loss can be reduced rather than returning to the suction side of another impeller, and the operating efficiency of the turbo compressor 1 can be improved further.

  Moreover, in the said embodiment, although the magnetic force generator 21 shall be arrange | positioned in the position facing the outer peripheral part of the back surface of the impeller 3 (or impeller 4), arrangement | positioning of the magnetic generator 21 is not limited to this. Further, it may be arranged at a position opposite to the outer peripheral portion of the back surface. Furthermore, for example, the magnetic force generator 21 can be disposed at each position shown in FIGS. 5A to 5E. In the following, the arrangement of the magnetic generator 21 corresponding to the impeller 3 is described, but the same applies to the arrangement of the magnetic generator 21 corresponding to the impeller 4. Moreover, illustration of the casing is abbreviate | omitted in FIG. 5A-FIG. 5E.

  For example, as shown in FIGS. 5A and 5B, the magnetic force generator 21 is a surface opposite to the back surface 3A of the impeller 3, that is, a surface on the inflow side of the gas to be compressed (hereinafter referred to as “surface 3B”). ) May be arranged substantially parallel to the axial direction. Note that the surface 3B includes not only a plane portion orthogonal to the axial direction (portion indicated by FIG. 5B) but also an inclined surface or a curved surface (portion indicated by FIG. 5A) of the outer peripheral portion. Further, for example, as shown in FIGS. 5C to 5E, the magnetic force generator 21 may be arranged on the radially outer side of the impeller 3. At this time, the magnetic force generator 21 may be arranged substantially parallel to the radial direction as shown in FIGS. 5C and 5D, or the magnetic force generator 21 is arranged obliquely with respect to the axial direction as shown in FIG. 5E. Also good.

  In the above embodiment, the moving device 22 moves the magnetic force generator 21 in the axial direction, that is, moves only with the moving component in the axial direction. However, as long as the moving device 22 moves at least with an axial moving component, for example, the moving device 22 moves the magnetic force generator 21 obliquely with respect to the axial direction, that is, the axial moving component and the radial moving component. It is good also as what moves with a movement component.

1 Turbo compressor (centrifugal rotating machine)
2 Rotating shaft 3 Impeller (1st impeller)
4 impeller (second impeller)
DESCRIPTION OF SYMBOLS 12 Intermediate cooler 13 Heat exchanger 20 Dynamic characteristic apparatus 21 Magnetic force generator 22 Moving apparatus 30 Cooling apparatus 31 Storage chamber 32 Refrigerant supply flow path 33 Refrigerant discharge flow path 34 Seal member 35 Refrigerant supply flow path 39 Refrigerant supply flow path

Claims (7)

A dynamic characteristic measuring device for a centrifugal rotating machine that compresses or pumps fluid by rotation of an impeller attached to a shaft end of a rotating shaft,
A magnetic force generator for exciting the impeller with a magnetic force;
A cooling device for cooling the magnetic force generator with a cooling medium;
An apparatus for measuring dynamic characteristics of a centrifugal rotating machine, comprising: The cooling device is
A storage chamber for storing the magnetic force generator;
A refrigerant supply channel for supplying the fluid before being compressed or pumped by the impeller to the storage chamber as the cooling medium;
A seal member provided between a wall surface of the storage chamber facing the impeller and the magnetic force generator penetrating the wall surface;
The apparatus for measuring dynamic characteristics of a centrifugal rotating machine according to claim 1, comprising: As the impeller, a first impeller that compresses or pumps fluid first, and a second impeller that further compresses or pumps fluid after the first impeller is provided,
When an intermediate cooler for cooling the fluid compressed or pumped by the first impeller is provided on the downstream side of the first impeller and the upstream side of the second impeller,
The cooling device is
A storage chamber in which the magnetic force generator for exciting the first impeller is stored;
A refrigerant supply flow path for supplying the fluid cooled by the intermediate cooler to the storage chamber as the cooling medium;
The apparatus for measuring dynamic characteristics of a centrifugal rotating machine according to claim 1, comprising: As the impeller, a first impeller that compresses or pumps fluid first, and a second impeller that further compresses or pumps fluid after the first impeller is provided,
When an intermediate cooler for cooling the fluid compressed or pumped by the first impeller is provided on the downstream side of the first impeller and the upstream side of the second impeller,
The cooling device is
A storage chamber in which the magnetic force generator for exciting the second impeller is stored;
A heat exchanger that cools the fluid compressed or pumped by the second impeller by heat exchange with the fluid cooled by the intermediate cooler;
A refrigerant supply channel for supplying the fluid cooled by the heat exchanger to the storage chamber as the cooling medium;
The apparatus for measuring dynamic characteristics of a centrifugal rotating machine according to claim 1, comprising:   5. The dynamic characteristic measurement device for a centrifugal rotating machine according to claim 1, wherein a refrigerant discharge passage for discharging the cooling medium from the storage chamber is connected to a suction side of the impeller.   The dynamic characteristic measurement device for a centrifugal rotating machine according to claim 5, wherein the refrigerant discharge channel is connected to a suction side of the impeller that is vibrated by the magnetic force generator cooled by the cooling device. A moving device for moving the magnetic force generator with at least a moving component in the axial direction of the rotating shaft;
The said cooling device is a dynamic characteristic measuring apparatus of the centrifugal rotary machine of any one of Claim 1 thru | or 6 which cools the said moving apparatus with the said magnetic force generator.

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