CN211397988U - Asymmetric centrifugal impeller fan - Google Patents
Asymmetric centrifugal impeller fan Download PDFInfo
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- CN211397988U CN211397988U CN201922296216.8U CN201922296216U CN211397988U CN 211397988 U CN211397988 U CN 211397988U CN 201922296216 U CN201922296216 U CN 201922296216U CN 211397988 U CN211397988 U CN 211397988U
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Abstract
The utility model provides an asymmetric centrifugal impeller fan. Comprises a shell, an impeller and a motor; the impeller is arranged in the shell and connected with an output shaft of the motor so as to realize the rotation of the impeller; the impeller comprises a front wheel disc, blades and a rear wheel disc which are sequentially connected along the axial direction of the impeller; the edge contour line of the free end part of the blade is an irregular curve and is used for reducing the rotation noise of the fan. The utility model discloses a set the edge contour line of the free end tip of the blade of impeller to the irregular curve, make the impeller when rotatory, the air current forms different pulse excitation at the free end tip of single blade, avoids producing single pulse excitation stack and produces concentrated frequency channel noise because of the free end tip of blade, and this fan reduces about 5dB than the fan noise of the adoption symmetrical formula impeller of equal aerodynamic performance.
Description
Technical Field
The utility model relates to a transformer cooling heat dissipation technical field, concretely relates to asymmetric centrifugal impeller fan.
Background
China railways are developing in a crossing mode, high-speed motor train units are distributed all over the country, and the traveling mode of people is more convenient and faster. In order to ensure the riding comfort of people and reduce the damage of the running of rolling stock to the environment along the line, the requirements of the motor train unit on noise and vibration are stricter, and even higher control requirements are provided according to different environmental conditions of the motor train unit during high-speed running, starting and stopping. The traction transformer needs to be cooled on the motor train unit. The cooling device takes away a large amount of heat generated by the traction transformer during working, and normal operation of equipment is guaranteed, so that running safety of the motor train unit is guaranteed. The cooling device of the traction transformer generally adopts a fan for forced air cooling, high noise generated by high-speed operation of the fan is a main source of noise of the cooling device, and the noise generated by the airflow machine is higher than 20dB of that generated by other equipment. With the increase of the traction weight and speed of different motor train units, the required traction power is also increased, the heat dissipation capacity required by the traction transformer is increased, the air volume and the air pressure of the air flow machine are correspondingly improved, but the generated noise and vibration quantity cannot be increased, and the conventional centrifugal ventilator for the traction transformer cooling device cannot meet the working conditions.
In view of the foregoing, there is a need for an asymmetric centrifugal impeller fan to solve the problems in the prior art.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide an asymmetric centrifugal impeller fan to solve the big problem of noise among the fan cooling process.
In order to achieve the purpose, the utility model provides an asymmetric centrifugal impeller fan, which comprises a casing, an impeller and a motor; the impeller is arranged in the shell and connected with an output shaft of the motor so as to realize the rotation of the impeller;
the impeller comprises a front wheel disc, blades and a rear wheel disc which are sequentially connected along the axial direction of the impeller; the edge contour line of the free end part of the blade is an irregular curve and is used for reducing the rotation noise of the fan.
Preferably, the impeller is provided with a plurality of blades which are irregularly distributed along the circumference of the impeller; the edge contour lines of the free end parts of the blades are different, so that the rotating noise of the fan is reduced.
Preferably, in a cross section perpendicular to the axial direction of the impeller, edge contour lines of free end portions of adjacent blades are arranged in a concavo-convex alternating state.
Preferably, a clamping groove is formed in the rear wheel disc, and clamping teeth are arranged at the connecting end of the blade and the rear wheel disc and used for improving the mounting and positioning accuracy of the blade on the rear wheel disc.
Preferably, the edge contour lines of the front wheel disc outer ring and the rear wheel disc outer ring are annular irregular curves so as to reduce the rotation noise of the fan.
Preferably, the cabinet includes an air inlet duct; the air inlet duct is trumpet-shaped, and the tail end of the air inlet duct extends into the air inlet end of the front wheel disc to smoothly guide external air into the impeller.
Preferably, the tail end of the air inlet duct and the air inlet end of the front wheel disc are 2-3 mm in radial clearance along the front wheel disc, so that air quantity leakage loss is reduced.
Preferably, the casing is provided with offset impeller mounting seats for forming a narrow acceleration zone and a wide pressure expansion zone of the airflow inside the casing.
Preferably, the casing is provided with an air outlet with a filter screen to prevent external foreign matters from entering the fan to damage the impeller rotating at high speed.
Preferably, the connecting part of the shell and the locomotive body is provided with a shock pad for reducing vibration and impact of the locomotive body on the fan and preventing the vibration of the fan from being transmitted to the locomotive body.
Use the technical scheme of the utility model, following beneficial effect has:
(1) the utility model discloses in, set the edge contour line of the free end tip through the blade with the impeller to the irregular curve, make the impeller when rotatory, the air current forms different pulse excitation at the free end tip of single blade, avoids producing because of the free end tip of blade single pulse excitation stack and produces concentrated frequency channel noise, and this fan reduces about 5dB than the fan noise of the adoption symmetrical formula impeller of equal aerodynamic performance.
(2) The utility model discloses in, the edge contour line of the free end tip of each blade on the impeller is all inequality for the air current is when the different blades of flowing through, and the pulse excitation of production is all inequality, and the pulse excitation that the air current produced in different blade departments can subduct or eliminate each other, thereby has reduced the rotational noise of fan.
(3) The utility model discloses in, the unsmooth state of curve that the edge profile line of the free end tip of adjacent blade is in following 2 axial same blocks of sections is opposite, and adjacent blade can produce opposite pulse excitation in the same blocks of sections of impeller axial, and pulse excitation between the adjacent blade can subdue by a wide margin or even offset completely, reduces the rotational noise of fan.
(4) The utility model discloses in, through the positioning channel section who sets up the blade on the rim plate of back, the blade passes through the latch and is connected with the back rim plate, has promoted the installation positioning accuracy of blade.
(5) The utility model discloses in, the edge profile line of preceding rim plate outer lane and back rim plate outer lane is cyclic annular irregular curve, when the airflow flows through the different radial position of preceding rim plate and back rim plate, produces different pulse excitation, can reduce the rotatory noise of fan.
(6) The utility model discloses in, the air inlet duct on the casing is loudspeaker form, rim plate air inlet end before the air inlet duct end stretches into, and the end of air inlet duct is 2 ~ 3mm along preceding rim plate radial gap with the air inlet end of preceding rim plate, the terminal outline line of air inlet duct is identical basically with the air inlet end outline line of preceding rim plate, can be with leading-in impeller of outside air fluently, make the air current get into the impeller with 2 ~ 5 attack angle, reduce the air current impact of the air inlet end of preceding rim plate, reach the mesh that reduces the vortex noise, reducible amount of wind leakage loss simultaneously, promote fan efficiency.
(7) The utility model discloses in, for eccentric settings between impeller and the casing, because the casing needs to satisfy the installation requirement, the external shape of casing is the box, and during impeller and casing eccentric settings, can be at the inside narrow district with higher speed and the spacious nip that expands of forming the air current of casing, ensure that the fan has sufficient air-out pressure.
(8) The utility model discloses in, through set up the shock pad in casing and locomotive body junction, set up the sealing washer between air-supply line and automobile body air-supply line, reducible locomotive automobile body is to the vibration and the impact that the fan produced, and the vibration of fan self has also been separated to the locomotive automobile body propagation simultaneously.
In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be described in further detail with reference to the drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. In the drawings:
FIG. 1 is a partial cross-sectional view of an asymmetric centrifugal impeller fan of the present application;
FIG. 2 is a schematic illustration of an irregular distribution of blades;
FIG. 3 is a schematic view of a blade configuration;
FIG. 4 is a schematic view of the eccentric arrangement of the casing and the impeller mounting seat;
FIG. 5 is a schematic diagram of the dislocation arrangement of the edge profiles of the outer rings of the front wheel disc and the rear wheel disc;
the air conditioner comprises a shell 1, a casing 1.1, an air inlet duct 1.2, an air outlet 1.3, a shock pad 2, an impeller 2.1, a front wheel disc 2.2, blades 2.2.1, a first blade, a second blade, a third blade, a fourth blade, a 2.2.5, a fifth blade, a 2.2.6, a sixth blade, a 2.2.7, a seventh blade, a 2.3, a rear wheel disc 3 and a motor.
Detailed Description
The embodiments of the invention will be described in detail hereinafter with reference to the accompanying drawings, but the invention can be implemented in many different ways, which are defined and covered by the claims.
Referring to fig. 1 to 5, the present embodiment is applied to cooling and heat dissipation of a locomotive traction transformer.
An asymmetric centrifugal impeller fan comprises a casing 1, an impeller 2 and a motor 3; the impeller 2 is arranged in the shell 1 and connected with an output shaft of the motor 3 to realize the rotation of the impeller 2;
the impeller 2 comprises a front wheel disc 2.1, blades 2.2 and a rear wheel disc 2.3 which are sequentially connected along the axial direction of the impeller 2; referring to fig. 1 and 3, the edge contour line of the free end of the blade 2.2 is an irregular curve, and the irregular curve is formed by arcs with different curvature radii, so as to avoid that when the edge contour line of the free end of the blade 2.2 is a straight line, a single pulse excitation superposition is generated along the axial direction of the impeller 2 when the airflow flows through the free end of the blade 2.2, and concentrated frequency band noise is generated.
Referring to fig. 2, the impeller 2 is provided with a plurality of blades 2.2, and the plurality of blades 2.2 are distributed irregularly along the circumference of the impeller 2; the distribution included angle alpha between one end of the adjacent blade 2.2 close to the wheel center (the rotation center of the impeller 2) and the wheel center connecting line is selected in the range:
360°/n±(360°/n×8％)
where n is the number of blades 2.2 on the impeller 2. The mounting position of the blade 2.2 is determined by modeling and analyzing the dynamic balance of the impeller 2, and the eccentricity of the wheel center of the impeller 2 is enabled to be less than or equal to 0.01mm during modeling and analyzing. In this embodiment, when the impeller 2 is provided with seven blades 2.2, the distribution included angles between the adjacent blades 2.2 are respectively 48 °, 52.6 °, 54.3 °, 48.9 °, 55 °, 51.1 °, and 50.1 ° according to modeling analysis.
Referring to fig. 3, the edge profiles of the free end portions of the blades 2.2 are different, and in this embodiment, the blades one 2.2.1, two 2.2.2, three 2.2.3, four 2.2.4, five 2.2.5, six 2.2.6 and seven 2.2.7, which are different from each other in the edge profile of the free end portion of the impeller 2, may cause the airflow to generate different pulse excitations when flowing through the different blades 2.2, so that the harmonic propagation of the airflow velocity flowing out of the impeller 2 is eliminated or blocked, thereby reducing the rotational noise of the impeller 2.
Referring to fig. 3, in a cross section perpendicular to the axial direction of the impeller 2, the edge contour lines of the free end portions of the adjacent blades 2.2 are arranged in a concave-convex alternating state, that is, the curved concave-convex states of the edge contour lines of the free end portions of the adjacent blades 2.2 in the same section along the axial direction of the impeller 2 are opposite, and fig. 3 is selected to describe that the blade six 2.2.6, the blade five 2.2.5 adjacent to the blade six 2.2.6 and the blade seven 2.2.7 are: the impeller is characterized in that three sections are axially divided along the impeller 2 and respectively comprise an AB section, a BC section and a CD section, in the AB section, the edge contour line of the free end part of the fifth blade 2.2.5 is in a convex state, the edge contour line of the free end part of the sixth blade 2.2.6 is in a concave state, and the edge contour line of the free end part of the seventh blade 2.2.7 is in a convex state; in the BC section, the edge contour line of the free end part deviated from the fifth blade 2.2.5 is in an inward concave state, the edge contour line of the free end part of the sixth blade 2.2.6 is in an outward convex state, and the edge contour line of the free end part of the seventh blade 2.2.7 is in an inward concave state; in the CD segment, the edge contour of the free end portion of vane five 2.2.5 which deviates from is convex, the edge contour of the free end portion of vane six 2.2.6 is concave, and the edge contour of the free end portion of vane seven 2.2.7 is convex. The arrangement can offset the pulse excitation formed by the airflow in different sections in the axial direction of the impeller 2, thereby reducing the rotation noise of the fan.
The rear wheel disc 2.3 is provided with a clamping groove, the connecting end of the blade 2.2 and the rear wheel disc 2.3 is provided with clamping teeth, the blade 2.2 is installed by determining the position of the clamping groove on the rear wheel disc 2.3, and the installation and positioning accuracy of the blade 2.2 on the rear wheel disc 2.3 can be improved.
Referring to fig. 5, the edge contour lines of the outer ring of the front wheel disc 2.1 and the outer ring of the rear wheel disc 2.3 are annular irregular curves, and the air flow does not generate single pulse excitation on the outer ring of the front wheel disc 2.1 and the outer ring of the rear wheel disc 2.3, so that the rotation noise of the fan is reduced. In this embodiment, the edge contour line of preceding rim plate 2.1 outer lane is the same and dislocation set with the edge contour line of back rim plate 2.3 outer lane, be about to the edge contour line of preceding rim plate 2.1 outer lane aligns the back with the edge contour line of back rim plate 2.3 outer lane, 2.1 rim plate along the rotation certain angle of wheel center before with, make the same radial position of the edge contour line of preceding rim plate 2.1 outer lane and the edge contour line of back rim plate 2.3 outer lane take place the dislocation, be used for forming in the front rim plate 2.1 and the same radial position of back rim plate 2.3 produce different pulse excitation, thereby reduce fan noise.
Referring to fig. 1, the cabinet 1 includes an air inlet duct 1.1; the air inlet duct 1.1 is horn-shaped, the tail end of the air inlet duct 1.1 extends into the air inlet end of the front wheel disc 2.1, the contour line of the tail end of the air inlet duct 1.1 is basically matched with the contour line of the air inlet end of the front wheel disc 2.1, so that external air is smoothly guided into the impeller 2, air flow enters the impeller 2 at an attack angle of 2-5 degrees, air flow impact of the air inlet end of the front wheel disc 2.1 is reduced, and the purpose of reducing eddy current noise is achieved.
The tail end of the air inlet duct 1.1 and the air inlet end of the front wheel disc 2.1 are in radial clearance of 2-3 mm along the front wheel disc 2.1, the air inlet duct 1.1 does not influence the rotation of the impeller 2 and simultaneously reduces air leakage loss, the efficiency of the fan is improved, and meanwhile, the generation of vortex can be reduced, and the vortex noise is reduced.
Referring to fig. 4, the casing 1 is provided with an offset impeller mount to form a narrow acceleration region and a wide pressure expansion region of the air flow inside the casing 1. In fig. 4, O is the axis of the output shaft of the motor 3, i.e., the axis of the impeller mounting seat; o' in fig. 4 is the center of the impeller mounting panel of the casing 1; wherein the eccentricity of O relative to O' satisfies the following relationship:
e1≤0.1l，e2≤0.1h
where l represents a lateral length dimension of the impeller mounting panel of the casing 1 and h represents a height dimension of the impeller mounting panel of the casing 1. Thus, the box-type casing 1 has a function similar to a spiral volute relative to the impeller 2, so that high-speed airflow from the impeller 2 is further accelerated in a relatively narrow area of the casing 1 to obtain larger kinetic energy, then the speed of the airflow flowing to a relatively wide area through the casing 1 is rapidly reduced, dynamic pressure is converted into static pressure, the fan is ensured to have enough outlet air pressure, and heat absorbed from a traction transformer is discharged to the atmosphere through the airflow.
Referring to fig. 1, the casing 1 is provided with an air outlet 1.2 having a screen, and the fan absorbs heat of the traction transformer from the air inlet duct 1.1 and discharges hot air to the atmosphere through the air outlet 1.2, thereby cooling the traction transformer. In the embodiment, rectangular meshes of 15 multiplied by 7mm are uniformly distributed on the plane of the screen plate, the screen plate mainly plays a role in filtering and protecting, and the fan impeller is prevented from being damaged by splashed foreign matters when the train moves forwards at a high speed.
Referring to fig. 1, a shock pad 1.3 is arranged at the joint of the casing 1 and the locomotive body to reduce the vibration and impact of the locomotive body on the fan and simultaneously prevent the vibration of the fan from being transmitted to the locomotive body. A sealing ring is arranged between the air inlet duct 1.1 and an air inlet pipeline of the locomotive body, so that the air inlet duct 1.1 is sealed, and vibration and impact between the air inlet duct 1.1 and the locomotive body are absorbed.
In this embodiment, the casing part of casing 1 adopts and to need only 4 weld welds to form after diversified bending, the turn-ups of air outlet 1.2 outwards being handled, and the casing mounting bracket is through bending the shaping many times to this has guaranteed that casing 1 has sufficient rigidity and good outward appearance, has promoted casing 1's vibration resistance, makes the fan have the little characteristics of vibration.
In this embodiment, the motor 3 is a pole-variable motor, and switches the number of poles according to a signal sent by a temperature sensor of the traction transformer, so as to achieve the purpose of energy saving; the motor 3 adopts a maintenance-free bearing, so that the maintenance period of the fan is prolonged, and the maintenance cost is saved; the motor 3 adopts an aluminum alloy base, and the purpose of light weight of the fan device is achieved.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. An asymmetric centrifugal impeller fan is characterized by comprising a casing (1), an impeller (2) and a motor (3); the impeller (2) is arranged in the shell (1) and connected with an output shaft of the motor (3) to realize the rotation of the impeller (2);
the impeller (2) comprises a front wheel disc (2.1), blades (2.2) and a rear wheel disc (2.3) which are sequentially connected along the axial direction of the impeller (2); the edge contour line of the free end part of the blade (2.2) is an irregular curve and is used for reducing the rotating noise of the fan.
2. An asymmetric centrifugal impeller fan according to claim 1, characterized in that the impeller (2) is provided with a plurality of blades (2.2), the plurality of blades (2.2) being distributed irregularly along the circumference of the impeller (2); the edge contour lines of the free end parts of the blades (2.2) are different, so that the rotation noise of the fan is reduced.
3. An asymmetric centrifugal impeller fan according to claim 2, characterized in that the edge contours of the free end portions of adjacent blades (2.2) are arranged in a concavo-convex alternating manner in a cross section perpendicular to the axial direction of the impeller (2).
4. The asymmetric centrifugal impeller fan as claimed in claim 1, wherein the rear wheel disc (2.3) is provided with a clamping groove, and the connecting end of the blade (2.2) and the rear wheel disc (2.3) is provided with a clamping tooth for improving the mounting and positioning accuracy of the blade (2.2) on the rear wheel disc (2.3).
5. An asymmetric centrifugal impeller fan according to claim 1, characterized in that the edge contour lines of the outer ring of the front wheel disc (2.1) and the outer ring of the rear wheel disc (2.3) are annular irregular curves for reducing the rotation noise of the fan.
6. An asymmetric centrifugal impeller fan according to claim 1, characterized in that the casing (1) comprises an air inlet duct (1.1); the air inlet duct (1.1) is horn-shaped, and the tail end of the air inlet duct (1.1) extends into the air inlet end of the front wheel disc (2.1) to smoothly guide external air into the impeller (2).
7. The asymmetric centrifugal impeller fan as claimed in claim 6, wherein the radial gap between the end of the air inlet duct (1.1) and the air inlet end of the front wheel disc (2.1) is 2-3 mm along the front wheel disc (2.1) to reduce the air leakage loss.
8. An asymmetric centrifugal impeller fan according to claim 1, characterized in that the casing (1) is provided with offset impeller mounts for creating a narrow acceleration zone and a wide expansion zone of the airflow inside the casing (1).
9. An asymmetric centrifugal impeller fan according to claim 1, characterized in that the casing (1) is provided with air outlets (1.2) with screens to prevent foreign objects from entering the fan and damaging the impeller (2) rotating at high speed.
10. The asymmetric centrifugal impeller fan as claimed in claim 1, wherein the connection between the casing (1) and the locomotive body is provided with a shock pad (1.3) for reducing the vibration and impact of the locomotive body on the fan and blocking the transmission of the vibration of the fan itself to the locomotive body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922296216.8U CN211397988U (en) | 2019-12-19 | 2019-12-19 | Asymmetric centrifugal impeller fan |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922296216.8U CN211397988U (en) | 2019-12-19 | 2019-12-19 | Asymmetric centrifugal impeller fan |
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| CN211397988U true CN211397988U (en) | 2020-09-01 |
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| CN201922296216.8U Active CN211397988U (en) | 2019-12-19 | 2019-12-19 | Asymmetric centrifugal impeller fan |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021169219A1 (en) * | 2020-02-26 | 2021-09-02 | 中山宜必思科技有限公司 | Fan wheel and fan using fan wheel |
| CN114810671A (en) * | 2022-06-27 | 2022-07-29 | 佛山市南海九洲普惠风机有限公司 | Special high-speed centrifugal fan of small-size dust remover |
-
2019
- 2019-12-19 CN CN201922296216.8U patent/CN211397988U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021169219A1 (en) * | 2020-02-26 | 2021-09-02 | 中山宜必思科技有限公司 | Fan wheel and fan using fan wheel |
| CN114810671A (en) * | 2022-06-27 | 2022-07-29 | 佛山市南海九洲普惠风机有限公司 | Special high-speed centrifugal fan of small-size dust remover |
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