CN116378879A - Device for measuring pulsating pressure of rotor blade - Google Patents
Device for measuring pulsating pressure of rotor blade Download PDFInfo
- Publication number
- CN116378879A CN116378879A CN202310611252.7A CN202310611252A CN116378879A CN 116378879 A CN116378879 A CN 116378879A CN 202310611252 A CN202310611252 A CN 202310611252A CN 116378879 A CN116378879 A CN 116378879A
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- Prior art keywords
- rotor blade
- water
- impeller
- pressure sensor
- measuring
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 113
- 230000007246 mechanism Effects 0.000 claims abstract description 39
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000000741 silica gel Substances 0.000 claims abstract description 6
- 229910002027 silica gel Inorganic materials 0.000 claims abstract description 6
- 230000001681 protective effect Effects 0.000 claims description 10
- 230000000149 penetrating effect Effects 0.000 claims description 6
- 230000008878 coupling Effects 0.000 claims description 2
- 238000010168 coupling process Methods 0.000 claims description 2
- 238000005859 coupling reaction Methods 0.000 claims description 2
- 238000012545 processing Methods 0.000 abstract description 9
- 230000010349 pulsation Effects 0.000 abstract description 6
- 230000002596 correlated effect Effects 0.000 abstract 1
- 238000002474 experimental method Methods 0.000 description 12
- 238000000034 method Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 8
- 230000008859 change Effects 0.000 description 6
- 239000007788 liquid Substances 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 230000005611 electricity Effects 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 238000009530 blood pressure measurement Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000035485 pulse pressure Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03B—MACHINES OR ENGINES FOR LIQUIDS
- F03B11/00—Parts or details not provided for in, or of interest apart from, the preceding groups, e.g. wear-protection couplings, between turbine and generator
- F03B11/008—Measuring or testing arrangements
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
The invention discloses a device for measuring the pulsating pressure of a rotor blade, which comprises: the hydraulic model, the water diversion mechanism, the diversion mechanism to and data acquisition and analysis unit, data acquisition and analysis unit are connected with pressure sensor, stopper, diversion mechanism respectively, and the hydraulic model includes: the rotor blade, at least one pressure sensor that is correlated with rotor blade, rotatory impeller are equipped with a plurality of and rotor blade matched with constant head tank on the rotatory impeller lateral wall, and the bottom central point of constant head tank puts and is equipped with the wire casing hole that runs through rotatory impeller, is equipped with the silica gel plug in the wire casing hole, and constant head tank and rotor blade grafting department is equipped with the screw, impeller shaft, and the impeller shaft drives rotatory impeller rotates, and through the relevant parameter of adjustment rotor blade, pressure sensor is with the pulsation pressure feedback on the rotor blade to data acquisition and the processing in the analysis unit, finds out the law, makes the blade can more reasonable distribution on the impeller, keeps the stability of unit.
Description
Technical Field
The invention belongs to the technical field of machine testing, and particularly relates to a device for measuring the pulsating pressure of a rotor blade.
Background
Along with the increase of the single-machine capacity of the water turbine and the components of the water turbine, the safe and stable operation of the water turbine is particularly important, the factors influencing the stable operation of the water turbine are many, the pulsating pressure is one of the important factors, the pulsating pressure of the water turbine possibly forms excessive mechanical stress on the instantaneous excessive load of the convection component and alternating stress on the water turbine, so that certain components of the water turbine are fatigued and damaged, in addition, if the pulsating pressure frequency coincides with the fixed frequency of the components of the water turbine, the resonance of the mechanical components can be caused, the safety and stability of the water turbine and even the whole plant can be directly influenced, and therefore, the measuring precision of the pulsating pressure should be improved in the simulation experiment of the water turbine.
At present, only the pulsation pressure on a fixed rotor blade on the turbine is measured for data acquisition and analysis, however, when relevant parameters of the rotor blade are adjusted, the rule of how the pulsation pressure on the rotor blade generates is unknown.
Disclosure of Invention
Aiming at the defects of the prior art, the embodiment of the application provides a device for measuring the pulsation pressure of a rotor blade, which solves the technical problem of how the pulsation pressure on the rotor blade generates a change rule when relevant parameters of the rotor blade are adjusted, and a conclusion is obtained through data acquisition and analysis, so that the rotor blade can be more reasonably distributed on an impeller, and the stability of a unit is maintained.
An embodiment of the present application provides an apparatus for measuring rotor blade pulsating pressure, comprising: the hydraulic model, the water guide mechanism, the delivery port of water guide mechanism just faces rotor blade direction, the water guide mechanism water outlet end with the water inlet end of water guide mechanism is connected, the outside water inlet is connected to the water inlet end of water guide mechanism to and data acquisition and analysis unit, data acquisition and analysis unit respectively with pressure sensor the stopper the water guide mechanism electricity is connected.
The hydraulic model comprises: the rotor blade, be equipped with the location arch on the rotor blade, at least one pressure sensor that associates with rotor blade, at least one pressure sensor location is in on the rotor blade, and keep away from rotor blade's blade root position department, rotatory impeller, be equipped with a plurality of with rotor blade location arch matched with positioning groove on the rotatory impeller lateral wall, positioning groove's bottom central point puts and is equipped with and runs through rotatory impeller, and be used for the wire casing hole that the cable passed through, be equipped with the silica gel plug in the wire casing hole, positioning groove with rotor blade grafting department one side is equipped with the screw, the impeller axle, impeller axle one end is connected with the stopper through the shaft coupling, the other end of impeller axle with rotatory impeller is connected, just the impeller axle drives rotatory impeller rotates.
Preferably, the embodiment of the application also discloses that the inside of the impeller shaft is of a hollow structure and is used for penetrating through a connecting cable connected with the pressure sensor, and the impeller shaft and the connecting cable synchronously rotate.
Preferably, the embodiment of the application also discloses that an electric conduction slip ring is arranged in the coupler, and the data acquisition and analysis unit is electrically connected with the pressure sensor through the electric conduction slip ring.
Preferably, the embodiment of the application also discloses that the water guide mechanism comprises a body and a water inlet pipe, wherein the front end of the body is provided with a rotating body penetrating through a plurality of fine holes, one end far away from the fine holes is embedded into the body, and the outer surface of the rotating body is provided with anti-skid protruding points.
Preferably, the embodiment of the application also discloses a water tank further comprising an n-shaped protective cover and an upper cover opening, wherein the n-shaped protective cover is sleeved on the rotary impeller, two sides of the bottom of the n-shaped protective cover are positioned in the water tank, and the water tank is connected with the water inlet end of the water diversion mechanism, so that a closed circulation system is formed, and the water resource can be reasonably recycled while the environment is protected.
Preferably, the embodiment of the application also discloses that one side of the water tank is provided with a water level gauge, the change of the water level is observed at any time, and the bottom of the water tank is provided with a water outlet, so that the liquid in the water tank is conveniently treated.
Preferably, the embodiment of the application further discloses that the water outlet end of the water diversion mechanism is connected with the water inlet pipe of the water diversion mechanism through a first hose, and the water inlet end of the water diversion mechanism is connected with the water tank through a second hose.
According to the technical scheme provided by the embodiment of the application, the remarkable effect is achieved:
(1) The rotor blade is fixedly arranged in the positioning groove of the rotating impeller by threads, the number, arrangement position and angle among the rotor blades are adjusted, the generated pulsating pressure data are collected and analyzed, the change rule of the pulsating pressure generated by adjusting the parameters of the rotor blades is confirmed, and the rotor blades can be reasonably distributed on the rotating impeller, so that the stability of the unit is maintained.
(2) Because the n-shaped protective cover is sleeved on the rotary impeller, two sides of the bottom of the protective cover are arranged in the water tank, and the water tank is connected with the water inlet end of the water diversion mechanism, the whole device forms a closed loop circulation system, and related data can be repeatedly collected.
(3) Because the liquid level meter is arranged on one side of the water tank, the change of the water level can be observed at any time, and the water outlet is arranged at the bottom of the water tank, so that the liquid in the water tank can be conveniently treated.
Drawings
FIG. 1 is a front view of a rotor blade pulse pressure measurement in an embodiment of the present application.
FIG. 2 is a top view of one embodiment of the present application for measuring rotor blade pulsating pressure.
FIG. 3 is a plan view of an impeller model in an embodiment of the present application.
Fig. 4 is a plan view of experiment 1 of the embodiment of the present application.
Fig. 5 is a plan view of experiment 2 of the embodiment of the present application.
Fig. 6 is a plan view of experiment 3 of the embodiment of the present application.
Fig. 7 is a plan view of experiment 4 of the embodiment of the present application.
Fig. 8 is a plan view of experiment 5 of the present embodiment.
Fig. 9 is a plan view of experiment 6 of the present embodiment.
Wherein the reference numerals are as follows:
1. the hydraulic system comprises a hydraulic model, 11, rotor blades, 12, a pressure sensor, 13, a rotary impeller, 131, a positioning groove, 132, a wire slot hole, 133, a silica gel plug, 14, an impeller shaft, 15, a protective cover, 2, a water guide mechanism, 3, a water guide mechanism, 4, a data acquisition and analysis unit, 5 and a water tank.
Description of the embodiments
The embodiment of the application solves the technical problem of a change rule of the pulsating pressure on the blade when the relevant parameters of the blade are adjusted by providing the device for measuring the pulsation of the rotor blade, and the technical scheme in the embodiment of the application is as follows:
the rotor blades 11 are clamped in the positioning grooves 131 of the rotating impeller 13 and are fixed by threads, the number and arrangement positions of the rotor blades 11 and the angles among the rotor blades 11 are adjusted, the data of the generated pulsating pressure are collected and analyzed, the change rule of the pulsating pressure generated by adjusting the parameters of the rotor blades 11 is confirmed, the rotor blades 11 can be more reasonably distributed on the rotating impeller 13, and the stability of the unit is maintained.
As shown in fig. 1-3, an embodiment of the present application provides an apparatus for measuring rotor blade pulsating pressure, comprising: the hydraulic model 1, the water guide mechanism 2, the delivery port of water guide mechanism 2 just faces rotor blade 11 direction, water guide mechanism 2 includes body and inlet tube, the front end of body is equipped with the rotator that runs through a plurality of pore, keep away from the one end of pore and imbeds in the body, and the rotator surface is equipped with anti-skidding bump, water guide mechanism 3 goes out the water end and is connected with the water inlet of water guide mechanism 2, water guide mechanism's water inlet end connects outside water inlet, and data acquisition and analysis unit 4, data acquisition and analysis unit 4 respectively with pressure sensor 12, the stopper, water guide mechanism 3 electricity is connected.
The hydraulic model 1 includes: the rotor blade 11 is provided with a positioning bulge, at least one pressure sensor 12 associated with the rotor blade 11 is positioned on the rotor blade 11 and far away from the blade root position of the rotor blade 11, the rotor blade 13 is provided with a plurality of positioning grooves 131 matched with the positioning bulge of the rotor blade 11 on the outer side wall of the rotor blade 13, the bottom center position of the positioning grooves 131 is provided with a wire slot hole 132 penetrating the rotor blade and used for passing a cable, a silica gel plug 133 is arranged in the wire slot hole 132, and one side of the splicing position of the positioning grooves 131 and the rotor blade 11 is provided with a screw hole;
the impeller shaft 14, one end of the impeller shaft 14 is connected with a brake through a coupler, the other end of the impeller shaft 14 is connected with the rotary impeller 13, and the impeller shaft 14 drives the rotary impeller 13 to rotate.
The inside of the impeller shaft 14 is of a hollow structure and is used for penetrating through a connecting cable connected with the pressure sensor 12, the impeller shaft 14 and the connecting cable synchronously rotate, a conductive slip ring is arranged in the coupler, and the data acquisition and analysis unit 4 is electrically connected with the pressure sensor 12 through the conductive slip ring.
Still include n shape protection casing 15 and upper cover open-ended water tank 5, n shape protection casing 15 cover is established on rotatory impeller 13, and n shape protection casing 15 bottom both sides are located the inside of water tank 5, and water tank 5 is connected with the water inlet end of diversion mechanism 3, makes it form closed circulation system, and one side of water tank 5 is equipped with the fluviograph, observes the water level variation at any time, and the bottom of water tank 5 is equipped with the outlet, conveniently handles the liquid in its water tank 5.
The working process comprises the following steps:
before the work starts, the positioning protrusions arranged on the rotor blades 11 are clamped in the positioning grooves 131 of the rotating impeller 13, the positioning protrusions are fixed through threads, part of water is injected into the water tank 5, the silica gel plug 133 in the wire slot hole 132 is opened, the conveying cable of the pressure sensor 12 associated with the rotor blades 11 enters the hub of the rotating impeller 13 through the wire slot hole 132 which is arranged at the center position of the bottom of the positioning grooves 131, the conveying cable rotates synchronously with the rotating impeller 13 during the work, the positioning grooves 131 of the rotor blades 11 are not arranged, the wire slot hole 132 is in a closed state, the starting device starts to operate, the water diversion mechanism 3 enables the water tank 5 to flow into the water diversion mechanism 2, water flow ejected by the water diversion mechanism 2 is in a stable state through adjusting the rotating body of the water diversion mechanism 2, the water diversion mechanism 2 is opposite to the rotating impeller 13, at the moment, the pressure sensor 12 receives signals to feed back the pressure value of the pressure sensor to the data acquisition and analysis unit 4 for processing, the sprayed water flow flows into the water tank 5 again through the n-shaped protective cover 15 during the rotating process of the rotating impeller 13, and a closed circulation system is formed, and water resources can be recycled reasonably.
As shown in fig. 4, in experiment 1, the number of rotor blades 11 is 3, the included angle between the rotor blades 11 is 120 degrees, and the rotor blades are symmetrically distributed, and the same process is not described in detail, and the pressure sensor 12 feeds back signals to the data acquisition and analysis unit 4 for processing.
As shown in fig. 5, in experiment 2, the number of rotor blades 11 is 6, the included angle between the rotor blades 11 is 60 degrees, and the rotor blades are symmetrically distributed, and the same process is not described in detail, and the pressure sensor 12 feeds back signals to the data acquisition and analysis unit 4 for processing.
As shown in fig. 6, in experiment 3, the number of rotor blades 11 is 9, the included angle between the rotor blades 11 is 60 degrees, and the rotor blades are symmetrically distributed, and the same process is not repeated. The pressure sensor 12 feeds back signals to the data acquisition and analysis unit 4 for processing.
As shown in fig. 7, in experiment 4, the number of rotor blades 11 is 3, the included angles between the rotor blades 11 are set values, and the rotor blades are asymmetrically distributed, and the same process is not described in detail, and the pressure sensor 12 feeds back signals to the data acquisition and analysis unit 4 for processing.
As shown in fig. 8, in experiment 5, the number of rotor blades 11 is 6, the included angles between the rotor blades 11 are set values, and the rotor blades are asymmetrically distributed, and the same process is not described in detail, and the pressure sensor 12 feeds back signals to the data acquisition and analysis unit 4 for processing.
As shown in fig. 9, in experiment 6, the number of rotor blades 11 is 9, the included angles between the rotor blades 11 are set values, and the rotor blades are asymmetrically distributed, and the same process is not described in detail, and the pressure sensor 12 feeds back signals to the data acquisition and analysis unit 4 for processing.
By analogy, the rules are found out by processing the data, so that the rotor blades 11 can be more reasonably distributed on the rotary impeller 13, and the stability of the unit is maintained.
While the preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts, and it is therefore intended that the appended claims be interpreted as including the preferred embodiments and all such variations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention, and it is intended that the invention encompass such modifications and variations as fall within the scope of the appended claims and their equivalents.
Claims (7)
1. An apparatus for measuring rotor blade pulsating pressure, comprising:
-a hydraulic model (1), comprising:
a rotor blade (11), wherein a positioning protrusion is arranged on the rotor blade (11);
-at least one pressure sensor (12) associated with the rotor blade (11), the at least one pressure sensor (12) being positioned on the rotor blade (11) at a blade root position remote from the rotor blade (11);
the rotary impeller (13), a plurality of positioning grooves (131) matched with the positioning protrusions of the rotor blades (11) are formed in the outer side wall of the rotary impeller (13), a wire slot hole (132) penetrating through the rotary impeller and used for a cable to pass through is formed in the center of the bottom of the positioning grooves (131), a silica gel plug (133) is arranged in the wire slot hole (132), and a screw hole is formed in one side of the splicing position of the positioning grooves (131) and the rotor blades (11);
the impeller shaft (14), one end of the impeller shaft (14) is connected with a brake through a coupler, the other end of the impeller shaft (14) is connected with the rotary impeller (13), and the impeller shaft (14) drives the rotary impeller (13) to rotate;
the water guide mechanism (2), the water outlet of the water guide mechanism (2) is opposite to the direction of the rotor blade (11);
the water diversion mechanism (3), the water outlet end of the water diversion mechanism (3) is connected with the water inlet end of the water diversion mechanism (2), and the water inlet end of the water diversion mechanism (3) is connected with an external water inlet; and
the data acquisition and analysis unit (4), the data acquisition and analysis unit (4) is respectively connected with the pressure sensor (12), the brake and the water diversion mechanism (3) electrically.
2. A device for measuring the pulsating pressure of a rotor blade according to claim 1, wherein the impeller shaft (14) has a hollow structure inside for passing through a connection cable connected to the pressure sensor (12), and the impeller shaft (14) rotates in synchronization with the connection cable.
3. Device for measuring the pulsating pressure of a rotor blade according to claim 1, wherein an electrically conductive slip ring is provided in the coupling, through which conductive slip ring the data acquisition and analysis unit (4) is electrically connected to the pressure sensor (12).
4. The device for measuring the pulsating pressure of the rotor blade according to claim 1, wherein the water guiding mechanism (2) comprises a body and a water inlet pipe, the front end of the body is provided with a rotating body penetrating through a plurality of fine holes, one end far away from the fine holes is embedded into the body, and the outer surface of the rotating body is provided with anti-slip protruding points.
5. The device for measuring the pulsating pressure of the rotor blade according to claim 1, further comprising an n-shaped protective cover (15) and a water tank (5) with an opening on an upper cover, wherein the n-shaped protective cover (15) is sleeved on the rotary impeller (13), two sides of the bottom of the n-shaped protective cover (15) are arranged inside the water tank (5), and the water tank (5) is connected with the water inlet end of the water diversion mechanism (3).
6. A device for measuring the pulsating pressure of a rotor blade according to claim 5, wherein the water tank (5) is provided with a level gauge on one side and a drain opening on the bottom of the water tank.
7. A device for measuring pulsating pressure of rotor blades according to claim 6, wherein the water outlet end of the water diversion means (3) is connected to the water inlet pipe of the water diversion means (2) by means of a first hose, and the water inlet end of the water diversion means (3) is connected to the water tank (5) by means of a second hose.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310611252.7A CN116378879A (en) | 2023-05-29 | 2023-05-29 | Device for measuring pulsating pressure of rotor blade |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310611252.7A CN116378879A (en) | 2023-05-29 | 2023-05-29 | Device for measuring pulsating pressure of rotor blade |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116378879A true CN116378879A (en) | 2023-07-04 |
Family
ID=86980926
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310611252.7A Pending CN116378879A (en) | 2023-05-29 | 2023-05-29 | Device for measuring pulsating pressure of rotor blade |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116378879A (en) |
-
2023
- 2023-05-29 CN CN202310611252.7A patent/CN116378879A/en active Pending
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