CN110513331A - A kind of low noise spiral case and centrifugal fan - Google Patents
A kind of low noise spiral case and centrifugal fan Download PDFInfo
- Publication number
- CN110513331A CN110513331A CN201910819955.2A CN201910819955A CN110513331A CN 110513331 A CN110513331 A CN 110513331A CN 201910819955 A CN201910819955 A CN 201910819955A CN 110513331 A CN110513331 A CN 110513331A
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- Prior art keywords
- volute tongue
- spacing
- radius
- spiral case
- tongue radius
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- 241000237858 Gastropoda Species 0.000 claims description 4
- 238000009423 ventilation Methods 0.000 claims description 4
- 230000009467 reduction Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 210000001367 artery Anatomy 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 238000013401 experimental design Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 210000003462 vein Anatomy 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
- F04D29/4206—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps
- F04D29/422—Discharge tongues
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
- F04D29/4206—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps
- F04D29/4226—Fan casings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/667—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps by influencing the flow pattern, e.g. suppression of turbulence
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/68—Combating cavitation, whirls, noise, vibration or the like; Balancing by influencing boundary layers
- F04D29/681—Combating cavitation, whirls, noise, vibration or the like; Balancing by influencing boundary layers especially adapted for elastic fluid pumps
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The invention discloses a kind of low noise spiral cases, including front shroud, back shroud, intermediate coaming plate and volute tongue, front shroud, back shroud and intermediate coaming plate surround airflow channel, the width direction of the spiral case is the width direction of volute tongue, in the width direction, volute tongue is divided into four sections, and volute tongue radius is from the first volute tongue radius r that volute tongue one end to the other end includes positioned at initial position1, the second volute tongue radius r2, third volute tongue radius r3, the 4th volute tongue radius r4And the 5th volute tongue radius r5, each volute tongue radius is with third volute tongue radius r3Centered on symmetrical, r1=r5, r2=r4；Spacing of the midpoint of circular arc apart from impeller outer edge corresponds to the first spacing t where each volute tongue radius1, the second spacing t2, third spacing t3, the 4th spacing t4And the 5th spacing t5, each spacing is third spacing t3Centered on symmetrical, t1=t5, t2=t4；Wherein t1> t2, t3> t2.The noise of centrifugal fan rotation is effectively reduced in the present invention.
Description
Technical field
The present invention relates to a kind of spiral case, especially a kind of low noise spiral case.
The present invention relates to a kind of centrifugal fan, especially a kind of centrifugal fan with low noise spiral case.
Background technique
Blade fluid machinery principle: blade is passed to the mechanical energy that prime mover generates therewith by making rotating motion
The gas of interaction makes to improve pressure.It is several that such machinery is divided into centrifugal, axial-flow type, mixed-flow again.Wherein multi-wing centrifugal
Formula blower is answered extensively because having outstanding advantages of biggish discharge coefficient, high pressure force coefficient, small size coefficient and low noise
With.
Noise is a kind of pollution, will affect daily life and work, reduces labor productivity.Centrifugal fan exists
Noise under normal operating conditions is dipole source, is mainly made of rotational noise and eddy current crack.The generation of rotational noise
Mechanism: one, due to strike when gas flows in impeller by blade, causes the pressure fluctuation of gas and generates noise；Two due to
The exit centrifugal fan Ye Dao will appear separation of flow area, the irregular movement of air-flow, and acts on the components such as volute tongue and generate pressure arteries and veins
Movable property gives birth to noise.Eddy current crack is mainly the noise as caused by the separation and radial clearance in boundary layer.
High speed and high pressure centrifugal fan noise is based on rotational noise, and conventional centrifugal ventilation blower is generally straight volute tongue
Structure, single structure are larger to the reduction limitation of noise, are unfavorable for the upgrading and progress of product.
Summary of the invention
For overcome the deficiencies in the prior art, the present invention provides a kind of low noise spiral cases that operation noise can be effectively reduced.
The technical solution adopted by the present invention to solve the technical problems is: a kind of low noise spiral case, including front shroud, rear cover
Plate, the intermediate coaming plate for connecting front shroud and back shroud and the volute tongue positioned at intermediate coaming plate air flow outlet, front shroud, after
Cover board and intermediate coaming plate surround airflow channel, and the width direction of the spiral case is the width direction of volute tongue, in the width direction
On, volute tongue is divided into four sections, and volute tongue radius is from the first snail that volute tongue one end to the other end includes positioned at initial position
Tongue radius r1, the second volute tongue radius r positioned at a quarter position2, third volute tongue radius r positioned at half position3, four
The radius of/tri- positions is the 4th volute tongue radius r4, and the 5th volute tongue radius r positioned at final position5, each volute tongue radius is with
Three volute tongue radius r3Centered on symmetrical, r1=r5, r2=r4；
Spacing of the midpoint of circular arc apart from impeller outer edge is the first spacing t where first volute tongue radius1, the second volute tongue
Spacing of the midpoint of circular arc apart from impeller outer edge is the second spacing t where radius2, where third volute tongue radius in circular arc
The spacing of point positional distance impeller outer edge is third spacing t3, the midpoint of circular arc is apart from impeller outer where the 4th volute tongue radius
The spacing of edge is the 4th spacing t4, between spacing of the midpoint of circular arc apart from impeller outer edge is the 5th where the 5th volute tongue radius
Away from t5, each spacing is third spacing t3Centered on symmetrical, t1=t5, t2=t4；
Wherein, 7mm≤r1=r5≤ 15mm, 7mm≤r2=r4≤ 15mm, 7mm≤r3≤ 15mm, r1> r2, r3> r2；
10mm≤t1=t5≤ 20mm, 10mm≤t2=t4≤ 20mm, 10mm≤t3≤ 20mm, t1> t2, t3> t2。
The beneficial effects of the present invention are:, by the improvement to volute tongue, revolving centrifugal fan on Casing width direction
It changes a job more uniform from circumferential mixing from the gas arrival volute tongue that impeller flows out when making, is staggered, reduces to the impulse phase in volute tongue
Impulsive force in volute tongue weakens the impact to volute tongue, so that the rotational noise of centrifugal fan greatly declines.
It is further arranged to: wherein r3> r1> r2；t3> t1> t2.Namely third volute tongue radius r3Size it is maximum, and
Second volute tongue radius r2Size it is minimum, third spacing t3Size it is maximum, the second spacing t2Size it is minimum, noise reduction effect is more
It is good.
It is further arranged to: in volute tongue width direction, the first volute tongue radius r1To the second volute tongue radius r2Size gradually
It reduces, the second volute tongue radius r2To third volute tongue radius r3Size be gradually increased.
It is further arranged to: in volute tongue width direction, the first spacing t1To the second spacing t2Size be gradually reduced,
Two spacing t2To third spacing t3Size be gradually increased.
It is further arranged to: the r1For 12mm, r2For 10mm, r3For 15mm, t1For 15mm, t2For 14mm, t3For
16.5mm.Structure after this optimization can obtain splendid noise reduction effect.
For overcome the deficiencies in the prior art, the present invention provides a kind of centrifugation ventilations that operation noise can be effectively reduced
Machine.
The technical solution adopted by the present invention to solve the technical problems is: a kind of centrifugal fan, includes spiral case and peace
Loaded on the impeller in spiral case, which is low noise spiral case above-mentioned.
The beneficial effects of the present invention are:, by the improvement to volute tongue, revolving centrifugal fan on Casing width direction
It changes a job more uniform from circumferential mixing from the gas arrival volute tongue that impeller flows out when making, is staggered, reduces to the impulse phase in volute tongue
Impulsive force in volute tongue weakens the impact to volute tongue, so that the rotational noise of centrifugal fan greatly declines.
By adopting the above technical scheme, centrifugal fan is forward multiple wing double-suction centrifugal pump ventilation blower.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the embodiment of the present invention.
Fig. 2 is the partial schematic diagram of volute tongue of the embodiment of the present invention.
Fig. 3 is the partial sectional view of the embodiment of the present invention, volute tongue and impeller position.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings:
Embodiment one: as shown in Figure 1, 2, 3, the present embodiment be spiral case 1, including front shroud 11, back shroud 12, for connecting
The intermediate coaming plate 13 of front shroud 11 and back shroud 12 and volute tongue 14 positioned at intermediate 13 air flow outlet of coaming plate, front shroud 11, after
Cover board 12 and intermediate coaming plate 13 surround airflow channel 15.The width direction of spiral case 1 is the width direction of volute tongue 14, in the width
On direction, volute tongue 14 is divided into four sections, and 14 radius of volute tongue includes being located at start bit from 14 one end of volute tongue to the other end
The the first volute tongue radius r set1, the second volute tongue radius r positioned at a quarter position2, third volute tongue positioned at half position
Radius r3, the radius of 3/4ths positions is the 4th volute tongue radius r4, and the 5th volute tongue radius r positioned at final position5, each snail
Tongue radius is with third volute tongue radius r3Centered on symmetrical, wherein r1=r5, r2=r4.As shown in figure 3, the first volute tongue radius r1Place
Spacing of the midpoint of circular arc apart from impeller outer edge is the first spacing t1, the second volute tongue radius r2The midpoint of place circular arc
Spacing apart from impeller outer edge is the second spacing t2, third volute tongue radius r3The midpoint of place circular arc is apart from impeller outer edge
Spacing is third spacing t3, the 4th volute tongue radius r4Spacing of the midpoint of place circular arc apart from impeller outer edge is the 4th spacing
t4, the 5th volute tongue radius r5Spacing of the midpoint of place circular arc apart from impeller outer edge is the 5th spacing t5, each spacing is with third
Spacing t3Centered on symmetrical, t1=t5, t2=t4.Due to the 4th volute tongue radius r4With the 5th volute tongue radius r5With the first volute tongue radius
r1With the second volute tongue radius r2It is symmetrical, therefore the 4th spacing t4With the 5th spacing t5It is not drawn into.
It is seen that the first volute tongue radius r1To the second volute tongue radius r2Transition be smooth curve namely the first snail
Tongue radius r1To the second volute tongue radius r2Size be gradually reduced；And the second volute tongue radius r2To third volute tongue radius r3Transition
It is similarly smooth curve namely the second volute tongue radius r2To third volute tongue radius r3Size be gradually increased.Due to each volute tongue radius
With third volute tongue radius r3Centered on symmetrical, therefore the 4th volute tongue radius r4With the 5th volute tongue radius r5It is also identical.Similarly,
First spacing t1To the second spacing t2Size be gradually reduced, the second spacing t2To third spacing t3Size be gradually increased, and with
Third spacing t3Centered on it is symmetrical.In process, because after knowing the volute tongue radius distance value at both ends, then natural between both ends
It is bent, smoothly transits, bending can satisfy the needs of the present embodiment, and since size itself is smaller, there is no need to know it
In curvature, be also able to achieve this programme.
In the present embodiment, r1=r5For 12mm, r2=r4For 10mm, r3For 15mm, t1=t5For 15mm, t2=t4For 14mm,
t3For 16.5mm.
In addition, r1To r5, t1To t5Other than the scheme disclosed in the present embodiment, they have corresponding value range,
The value range is as follows: 7mm≤r1=r5≤ 15mm, 7mm≤r2=r4≤ 15mm, 7mm≤r3≤ 15mm, r3> r1> r2；10mm
≤t1=t5≤ 20mm, 10mm≤t2=t4≤ 20mm, 10mm≤t3≤ 20mm, t3> t1> t2.And those skilled in the art can be with
It chooses within the range of value and sets 1 structure of spiral case, and can equally reach noise reduction effect identical or approximate with the present embodiment.
Embodiment two: the present embodiment is a kind of centrifugal fan, spiral case 1, impeller 2, frame, bearing, axis and motor, impeller
2 include blade, discs, and discs is equipped with wheel hub, and axis one end connects wheel hub, and the other end connects motor.Wherein spiral case 1 uses
Spiral case 1 disclosed in embodiment one.
Noise experiment: being directed to the running noise of embodiment two and master mould (conventional centrifugal blower), and experimental design will be implemented
Example two and master mould are placed in respectively under same sound insulation environment, in the oblique 45 degree of distances 1m position of sound production Mike in the outlet of blower object
Wind passes through the level of noise of microphone collecting test object in the operating condition.
In the above experimental group, group 1, group 2, group 3 are the scheme of embodiment two, and unique difference is r1、r2、r3、t1、t2、
t3Choosing value on have differences, and final result can be found, either organized noise figure measured by 1, group 2 or group 3 and be below
The noise figure (at least 1dB or more) of master mould.
Claims (7)
1. a kind of low noise spiral case including front shroud, back shroud, the intermediate coaming plate for connecting front shroud and back shroud and is located at
The volute tongue of intermediate coaming plate air flow outlet, front shroud, back shroud and intermediate coaming plate surround airflow channel, it is characterized in that: the snail
The width direction of shell is the width direction of volute tongue, and in the width direction, volute tongue is divided into four sections, and volute tongue radius
From the first volute tongue radius r that volute tongue one end to the other end includes positioned at initial position1, the second volute tongue positioned at a quarter position
Radius r2, third volute tongue radius r positioned at half position3, the radius of 3/4ths positions is the 4th volute tongue radius r4, and
The 5th volute tongue radius r positioned at final position5, each volute tongue radius is with third volute tongue radius r3Centered on symmetrical, r1=r5, r2=
r4；
Spacing of the midpoint of circular arc apart from impeller outer edge is the first spacing t where first volute tongue radius1, the second volute tongue radius
Spacing of the midpoint of place circular arc apart from impeller outer edge is the second spacing t2, the middle point of circular arc where third volute tongue radius
Setting the spacing apart from impeller outer edge is third spacing t3, the midpoint of circular arc is apart from impeller outer edge where the 4th volute tongue radius
Spacing is the 4th spacing t4, spacing of the midpoint of circular arc apart from impeller outer edge is the 5th spacing t where the 5th volute tongue radius5,
Each spacing is third spacing t3Centered on symmetrical, t1=t5, t2=t4；
Wherein, 7mm≤r1=r5≤ 15mm, 7mm≤r2=r4≤ 15mm, 7mm≤r3≤ 15mm, r1> r2, r3> r2；
10mm≤t1=t5≤ 20mm, 10mm≤t2=t4≤ 20mm, 10mm≤t3≤ 20mm, t1> t2, t3> t2。
2. low noise spiral case according to claim 1, it is characterized in that: wherein r3> r1> r2；t3> t1> t2。
3. low noise spiral case according to claim 2, it is characterized in that: in volute tongue width direction, the first volute tongue radius r1To
Two volute tongue radius r2Size be gradually reduced, the second volute tongue radius r2To third volute tongue radius r3Size be gradually increased.
4. low noise spiral case according to claim 2, it is characterized in that: in volute tongue width direction, the first spacing t1To between second
Away from t2Size be gradually reduced, the second spacing t2To third spacing t3Size be gradually increased.
5. low noise spiral case according to claim 1, it is characterized in that: the r1For 12mm, r2For 10mm, r3For 15mm, t1For
15mm, t2For 14mm, t3For 16.5mm.
The impeller that 6. a kind of centrifugal fan includes spiral case and is installed in spiral case, it is characterized in that: the spiral case is claim
Low noise spiral case described in 1~4.
7. centrifugal fan according to claim 6, it is characterized in that: the centrifugal fan is forward multiple wing double-suction centrifugal pump
Ventilation blower.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910819955.2A CN110513331A (en) | 2019-08-31 | 2019-08-31 | A kind of low noise spiral case and centrifugal fan |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910819955.2A CN110513331A (en) | 2019-08-31 | 2019-08-31 | A kind of low noise spiral case and centrifugal fan |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110513331A true CN110513331A (en) | 2019-11-29 |
Family
ID=68628900
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910819955.2A Pending CN110513331A (en) | 2019-08-31 | 2019-08-31 | A kind of low noise spiral case and centrifugal fan |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0648939A2 (en) * | 1993-10-18 | 1995-04-19 | Hitachi, Ltd. | Centrifugal fluid machine |
| DE19811877A1 (en) * | 1998-03-18 | 1999-09-23 | Motoren Ventilatoren Gmbh | Radial fan for heating the office or household |
| CN105756981A (en) * | 2016-04-26 | 2016-07-13 | 浙江理工大学 | Noise reduction fan wall for shell-free centrifugal fan |
| CN105756994A (en) * | 2016-04-26 | 2016-07-13 | 浙江理工大学 | High-efficiency low-noise volute centrifugal fan |
| CN105782076A (en) * | 2016-04-29 | 2016-07-20 | 浙江苏泊尔家电制造有限公司 | Centrifugal fan and kitchen ventilator |
| ITUB20160970A1 (en) * | 2016-02-23 | 2017-08-23 | E M C Electric Motors Company S R L | CENTRIFUGAL ELECTRIC FAN WITH SPECIAL GEOMETRIC DIMENSIONS. |
| CN108869405A (en) * | 2018-06-05 | 2018-11-23 | 广东海信家电有限公司 | A kind of double air intake centrifugal blowers and range hood |
| CN109973433A (en) * | 2019-02-27 | 2019-07-05 | 华中科技大学 | A kind of spiral case with concave incline tongue structure |
| CN211144903U (en) * | 2019-08-31 | 2020-07-31 | 浙江理工大学 | Low-noise volute and centrifugal ventilator |
-
2019
- 2019-08-31 CN CN201910819955.2A patent/CN110513331A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0648939A2 (en) * | 1993-10-18 | 1995-04-19 | Hitachi, Ltd. | Centrifugal fluid machine |
| US20010033792A1 (en) * | 1993-10-18 | 2001-10-25 | Yoshihiro Nagaoka | Centrifugal fluid machine |
| DE19811877A1 (en) * | 1998-03-18 | 1999-09-23 | Motoren Ventilatoren Gmbh | Radial fan for heating the office or household |
| ITUB20160970A1 (en) * | 2016-02-23 | 2017-08-23 | E M C Electric Motors Company S R L | CENTRIFUGAL ELECTRIC FAN WITH SPECIAL GEOMETRIC DIMENSIONS. |
| CN105756981A (en) * | 2016-04-26 | 2016-07-13 | 浙江理工大学 | Noise reduction fan wall for shell-free centrifugal fan |
| CN105756994A (en) * | 2016-04-26 | 2016-07-13 | 浙江理工大学 | High-efficiency low-noise volute centrifugal fan |
| CN105782076A (en) * | 2016-04-29 | 2016-07-20 | 浙江苏泊尔家电制造有限公司 | Centrifugal fan and kitchen ventilator |
| CN108869405A (en) * | 2018-06-05 | 2018-11-23 | 广东海信家电有限公司 | A kind of double air intake centrifugal blowers and range hood |
| CN109973433A (en) * | 2019-02-27 | 2019-07-05 | 华中科技大学 | A kind of spiral case with concave incline tongue structure |
| CN211144903U (en) * | 2019-08-31 | 2020-07-31 | 浙江理工大学 | Low-noise volute and centrifugal ventilator |
Non-Patent Citations (1)
| Title |
|---|
| 张玉良、朱祖超、李文广、周兆忠、肖俊建: "低比转速复合叶轮离心泵停机过程水力特性", 农业工程学报, vol. 34, no. 12, 15 August 2018 (2018-08-15), pages 95 - 103 * |
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