High-speed centrifugal compressor backward flow air cooling system
The technical field is as follows:
the invention relates to a backflow air cooling system of a high-speed centrifugal compressor.
Background art:
at present, the development of new energy fuel cell automobiles is considered as an important link of traffic energy power conversion, in order to ensure the normal work of a fuel cell engine, the engine generally needs auxiliary systems such as a hydrogen supply subsystem, an air supply subsystem and a circulating water cooling management subsystem, and a large number of researches show that the high-pressure and large-flow air supply has an obvious effect of improving the power output of the existing fuel cell engine. Therefore, before air enters the engine, the air intake is pressurized, and a centrifugal air compressor is an energy conversion device for achieving the aim, and is one of important parts of an air supply system of a fuel cell engine.
The structure of the conventional high-speed centrifugal compressor mainly comprises a shell, a stator and a main shaft, wherein a first-stage bearing seat and a second-stage bearing seat which are used for supporting the main shaft are respectively installed on the inner sides of two ends of the shell, a first-stage diffuser and a second-stage diffuser are respectively installed on the outer sides of two ends of the shell, a first-stage worm wheel and a second-stage worm wheel are respectively installed on two ends of the main shaft through the first-stage diffuser and the second-stage diffuser, and a first-stage volute and a second-stage volute are installed outside the first-stage worm wheel and the second-stage worm wheel. During operation, the main shaft rotating speed exceeds 10000r/min, because its rotational speed is very high, the during operation is inside can produce a large amount of heats, if these heats form the heat accumulation in time to discharge, can appear leading to the condition of being forced to shut down because of inside high temperature. At present generally all cool down centrifugal compressor through two kinds of forms of outside water-cooling and inside air-cooling, wherein, inside air-cooling form requires that the centrifugal compressor internals has the wind-guiding function, inside forms the reasonable route of conducting that supplies the air to march and just can fully cool down each part, and present inside air-cooling structure, inside route of conducting is single, the design is unreasonable, can only cool down individuality part, can't cool down each functional unit, the cooling effect is poor, therefore, need improve the design again to inside air-cooling structure.
In summary, the design problem of the internal air cooling structure of the high-speed centrifugal compressor has become a technical problem to be solved urgently in the industry.
The invention content is as follows:
the invention provides a high-speed centrifugal compressor backflow air cooling system for making up the defects of the prior art, and solves the problems that the conventional internal air cooling structure has a single conduction path, can only cool individual parts, cannot cool all functional parts and is poor in cooling effect.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a backflow air cooling system of a high-speed centrifugal compressor comprises a shell, a stator and a main shaft, wherein a first-stage bearing seat and a second-stage bearing seat for supporting the main shaft are respectively arranged on the inner sides of two ends of the shell, a first-stage diffuser and a second-stage diffuser are respectively arranged on the outer sides of two ends of the shell, a first-stage worm wheel and a second-stage worm wheel are respectively arranged on two ends of the main shaft which penetrate through the first-stage diffuser and the second-stage diffuser, a first-stage volute and a second-stage volute are respectively arranged outside the first-stage worm wheel and the second-stage worm wheel,
the primary diffuser comprises a diffuser body, an air inlet communicated with an inner cavity of the primary volute is formed in the diffuser body, a worm wheel hole is formed in the center of the diffuser body, a cooling air backflow cavity is formed in one side of the diffuser body, a plurality of air guide grooves are formed in the bottom of the cooling air backflow cavity and communicated with the worm wheel hole, a first annular air guide groove is formed in the diffuser body on the other side of the periphery of the cooling air backflow cavity, the cooling air backflow cavity is communicated with the first annular air guide grooves through a plurality of first air guide holes, the first air guide holes are communicated with the air guide grooves, a plurality of first bosses corresponding to thrust bearings are arranged on the other side of the diffuser body, a first air guide channel is formed between every two adjacent first bosses, and the first air guide channels are communicated with the worm wheel hole;
the first-stage bearing block comprises a bearing block body, a spindle hole is formed in the center of the bearing block body, a thrust bearing mounting groove is formed in one side of the bearing block body, a second annular air guide groove communicated with an air inlet hole is formed in the bearing block body on the periphery of the thrust bearing mounting groove, the thrust bearing mounting groove and the second annular air guide groove are communicated through a plurality of second air guide holes, a plurality of second bosses corresponding to the thrust bearing are arranged at the bottom of the thrust bearing mounting groove, second air guide channels communicated with the spindle hole are formed between every two adjacent second bosses, and a plurality of through holes communicated with the first annular air guide groove are formed in the bearing block body between the thrust bearing mounting groove and the second annular air guide groove;
the air in the inner cavity of the primary volute enters a second annular air guide groove from an air inlet, enters a thrust bearing mounting groove through a second air guide hole, one part of the air in the thrust bearing mounting groove enters a main shaft hole through a second air guide channel and is discharged to a gap between the stator and the main shaft through a radial air bearing, the other part of the air in the thrust bearing mounting groove enters a worm wheel hole through a first air guide channel and flows back to a cooling air backflow cavity, then enters a first air guide hole through the air guide groove, enters a first annular air guide groove from the first air guide hole, is discharged to the gap between the stator and the main shaft through a through hole from the first annular air guide groove, then enters a cavity between the secondary bearing seat and the secondary diffuser through a radial air bearing through a main shaft hole of the secondary bearing seat and is discharged outwards, and then is discharged to the outside the housing through a small hole on the housing.
The bottom of the second-stage diffuser is provided with an exhaust passage, the bottom of the shell is provided with an exhaust hole communicated with the exhaust passage, and air between the second-stage bearing seat and the second-stage diffuser is exhausted through the exhaust passage and the exhaust hole.
And a plurality of air guide blades are arranged on the diffuser body at the same side of the periphery of the cooling air backflow cavity along the circumference.
And a plurality of air outlet holes are formed between the first annular air guide groove and the outer end surface of the diffuser body.
And a radial air bearing mounting groove is formed in the bearing seat body.
And the bearing seat bodies on two sides of the radial air bearing mounting groove are provided with stop block grooves for mounting radial air bearings.
By adopting the scheme, the invention has the following advantages:
through improving the structure to one-level diffuser, one-level bearing frame, make inside forced air cooling structure optimize more, can cool down two thrust air bearings, two radial air bearing, main shaft and stator in the high-speed centrifugal compressor, the cooling effect is good, and inside heat can in time be discharged and can not form the heat and pile up, has avoided appearing leading to being forced the circumstances of shutting down because of inside high temperature.
Description of the drawings:
FIG. 1 is a schematic diagram of the internal air cooling route and the principle structure of the present invention.
Fig. 2 is a schematic front perspective view of a one-stage diffuser according to the present invention.
Fig. 3 is a schematic cross-sectional view of a one-stage diffuser according to the present invention.
Fig. 4 is a rear perspective view of the first-stage diffuser according to the present invention.
Fig. 5 is a schematic front perspective view of the primary bearing seat of the present invention.
FIG. 6 is a schematic sectional view of a primary bearing seat of the present invention.
Fig. 7 is a rear perspective view of the primary bearing seat of the present invention.
In the figure, 1, a shell, 2, a stator, 3, a main shaft, 4, a first-stage bearing seat, 5, a second-stage bearing seat, 6, a first-stage diffuser, 7, a second-stage diffuser, 8, a first-stage worm wheel, 9, a second-stage worm wheel, 10, a first-stage volute, 11, a second-stage volute, 12, a diffuser body, 13, an air inlet hole, 14, a worm wheel hole, 15, a cooling air backflow cavity, 16, an air guide groove, 17, a first annular air guide groove, 18, a first air guide hole, 19, a first boss, 20, a first air guide channel, 21, a bearing seat body, 22, a main shaft hole, 23, a thrust bearing mounting groove, 24, a second annular air guide groove, 25, a second air guide hole, 26, a second boss, 27, a second air guide channel, 28, a through hole, 29, an exhaust channel, 30, an exhaust hole, 31, an air guide vane, 32, an air outlet hole, 33, a radial air bearing mounting groove, 34 and a block groove are included in the figure.
The specific implementation mode is as follows:
in order to clearly explain the technical features of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings.
As shown in fig. 1-7, a high-speed centrifugal compressor backflow air cooling system comprises a housing 1, a stator 2 and a main shaft 3, wherein a first-stage bearing seat 4 and a second-stage bearing seat 5 for supporting the main shaft 3 are respectively installed on the inner sides of two ends of the housing 1, a first-stage diffuser 6 and a second-stage diffuser 7 are respectively installed on the outer sides of two ends of the housing 1, a first-stage worm wheel 8 and a second-stage worm wheel 9 are respectively installed on two ends of the main shaft 3 which penetrate through the first-stage diffuser 6 and the second-stage diffuser 7, a first-stage volute 10 and a second-stage volute 11 are respectively installed outside the first-stage worm wheel 8 and the second-stage worm wheel 9,
the first-stage diffuser 6 comprises a diffuser body 12, an air inlet 13 communicated with the inner cavity of the first-stage volute 10 is formed in the diffuser body 12, a worm wheel hole 14 is formed in the center of the diffuser body 12, a cooling air backflow cavity 15 is formed in one side of the diffuser body 12, a plurality of air guide grooves 16 are formed in the bottom of the cooling air backflow cavity 15, the air guide grooves 16 are communicated with the worm wheel hole 14, a first annular air guide groove 17 is formed in the diffuser body 12 on the other side of the periphery of the cooling air backflow cavity 15, the cooling air backflow cavity 15 is communicated with the first annular air guide grooves 17 through a plurality of first air guide holes 18, the first air guide holes 18 are communicated with the air guide grooves 16, a plurality of first bosses 19 corresponding to thrust bearings are formed in the other side of the diffuser body 12, first air guide channels 20 are formed between adjacent first bosses 19, and the first air guide channels 20 are communicated with the worm wheel hole 14;
the first-stage bearing seat 4 comprises a bearing seat body 21, a spindle hole 22 is formed in the center of the bearing seat body 21, a thrust bearing mounting groove 23 is formed in one side of the bearing seat body 21, a second annular air guide groove 24 communicated with the air inlet hole 13 is formed in the bearing seat body 21 on the periphery of the thrust bearing mounting groove 23, the thrust bearing mounting groove 23 is communicated with the second annular air guide groove 24 through a plurality of second air guide holes 25, a plurality of second bosses 26 corresponding to thrust bearings are arranged at the bottom of the thrust bearing mounting groove 23, a second air guide channel 27 communicated with the adjacent second bosses 26 is formed between the adjacent second bosses 26, the second air guide channel 27 is communicated with the spindle hole 22, and a plurality of through holes 28 communicated with the first annular air guide groove 17 are formed in the bearing seat body 21 between the thrust bearing mounting groove 23 and the second annular air guide groove 24;
the air in the inner cavity of the primary volute 10 enters the second annular air guide groove 24 from the air inlet hole 13 and enters the thrust bearing mounting groove 23 through the second air guide hole 25, after a part of the air in the thrust bearing mounting groove 23 cools one of the thrust bearings, enters the main shaft hole 22 through the second air guide channel 27, is discharged to the gap between the stator 2 and the main shaft 3 through the radial air bearing, and after the other part cools the other thrust bearing, the cooling air flows back to the cooling air return cavity 15 through the first air guide channel 20, enters the worm wheel hole 14, enters the first air guide hole 18 through the air guide groove 16, enters the first annular air guide groove 17 from the first air guide hole 18, is discharged to a gap between the stator 2 and the main shaft 3 from the first annular air guide groove 17 through the through hole 28, and then enters a cavity between the secondary bearing seat 5 and the secondary diffuser 7 through the main shaft hole of the secondary bearing seat 5 and the radial air bearing to be discharged outwards. The bottom of the second-stage diffuser 7 is provided with an exhaust passage 29, the bottom of the shell 1 is provided with an exhaust hole 30 communicated with the exhaust passage 29, and air between the second-stage bearing seat 5 and the second-stage diffuser 7 is exhausted outwards through the exhaust passage 29 and the exhaust hole 30.
A plurality of air guide blades 31 are arranged on the diffuser body 12 on the same side of the periphery of the cooling air return cavity 15 along the circumference, and the air guide blades 31 are matched with the first-stage worm wheel 8, so that the air compression efficiency can be improved.
A plurality of air outlet holes 32 are formed between the first annular air guide groove 17 and the outer end face of the diffuser body 12, one part of air entering the first annular air guide groove 17 is discharged into the centrifugal compressor to cool the inside of the centrifugal compressor, and the other part of air is directly discharged into the first-stage compression cavity from the air outlet holes 32 and is continuously conveyed to the second-stage compression cavity.
The bearing seat body 21 is provided with a radial air bearing installation groove 33, the radial air bearing installation groove 33 is used for installing a radial air bearing, on the other hand, a part of air can enter the radial air bearing installation groove 33 from the spindle hole 22 and is discharged backwards to a gap between the stator 2 and the spindle 3, and the air in the spindle hole 22 can play a cooling role on the radial air bearing.
The bearing seat body 21 on two sides of the radial air bearing mounting groove 33 is provided with a stop groove 34 for mounting the radial air bearing, and a stop is mounted in the stop groove 34 through a screw and used for fixing the radial air bearing.
The above-described embodiments should not be construed as limiting the scope of the invention, and any alternative modifications or alterations to the embodiments of the present invention will be apparent to those skilled in the art.
The present invention is not described in detail, but is known to those skilled in the art.