CN110145481A - It is a kind of to enter the wind mouth circle and using the centrifugal blower for having the air inlet mouth circle - Google Patents
It is a kind of to enter the wind mouth circle and using the centrifugal blower for having the air inlet mouth circle Download PDFInfo
- Publication number
- CN110145481A CN110145481A CN201910463522.8A CN201910463522A CN110145481A CN 110145481 A CN110145481 A CN 110145481A CN 201910463522 A CN201910463522 A CN 201910463522A CN 110145481 A CN110145481 A CN 110145481A
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- Prior art keywords
- circle
- center
- diversion division
- air inlet
- radial
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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
- F04D25/00—Pumping installations or systems
- F04D25/02—Units comprising pumps and their driving means
- F04D25/08—Units comprising pumps and their driving means the working fluid being air, e.g. for ventilation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/001—Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring
-
- 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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- 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 air inlet mouth circles, including diversion division, the diversion division includes radial diversion division, it is described radial direction diversion division radial outside in the axial direction be projected as circle and have first center of circle, it is described radial direction diversion division radially inner side in the axial direction be projected as circle and have second center of circle, it is characterised in that: first center of circle and second center of circle are not overlapped.Also disclose the centrifugal blower that a kind of application has air inlet mouth circle as described above, it is characterised in that: including spiral case and the impeller being arranged in spiral case, be formed with air inlet and air outlet on the spiral case.Compared with prior art, the present invention has the advantages that by so that the eccentric air inlet mouth circle for constituting variable cross-section in the inside and outside center of circle of air inlet mouth circle, the vortex of air inlet can be made more stable, intensity is bigger, the position of vortex and distribution are mobile to impeller center, flow increases in entire condition range, and efficiency reaches full working scope covering in entire condition range, is highly improved.
Description
Technical field
The present invention relates to power device, especially a kind of air inlet mouth circle, and application have the centrifugal blower of the air inlet mouth circle.
Background technique
Air inlet mouth circle is one of the main component in multi-wing centrifugal fan.Common air inlet mouth circle form has cylinder-shaped, circular cone
Shape, arc, arc-shaped, arc tubular and cone arc, effect are to guarantee that air-flow can equably be full of impeller inlet section, reduce stream
Dynamic loss.Therefore the structural shape of collector, inlet and outlet size and installation site can all cause the interior stream of entire blower fan system
Large effect, to influence the performance and noise of blower.
It is compared with the blower of other patterns, multi-wing centrifugal fan leaf road is short and intensive, can obtain relatively when running
High pressure and noise, therefore the domestic electric appliance that is widely used.But in most of application scenarios, blower is not independent
Operation, often there are complicated flow passage components or complete machine structure to be connected in series therewith, blower also and there is no it is ideal freely into
Mouthful space, in range hood in order to collect, cross filtering fume, in the blower fan system import side's of being provided with chamber and guiding device, blower
The air flow condition of leading portion is suffered restraints and is limited.There is now research and utilization PIV under the conditions of restricted fan inlet region into
It has gone measurement, it is found that it is consistent non-fixed with impeller direction of rotation small flow and best efficiency point operating condition fan inlet region all exist
Normal vortex, this whirlpool influence the performance of kitchen ventilator, as shown in Figure 6.
Existing air inlet mouth circle, a kind of forward multiple wing as disclosed in the Chinese patent application No. is 200920272495.8 from
Heart volute of blower, including snail plate, the duct ring on snail plate and the outlet on snail plate, duct ring is in class ellipse, to improve
Fan performance and reduction noise；For another example a kind of low-noise fan disclosed in the Chinese patent application No. is 201811272111.2 and
Kitchen ventilator, including spiral case, spiral case are equipped with interconnected air inlet and air outlet, and spiral case is equipped with barrier component, barrier portion
Part shield portions air inlet, and occlusion area is corresponding with the volute tongue position on spiral case.
It can be seen that in the prior art, when studying influence of the air inlet to fan performance, only considering that blower is individually being transported
In row environment, there is no distinguishing whether air inlet mouth circle leading portion air-flow suffers restraints, if only thinking state air inlet blower is resonable
The result of study of condition directly migrates to the environment of blower not isolated operation, this is inaccurate.
Summary of the invention
First technical problem to be solved by this invention be in view of the above-mentioned problems of the prior art, provide it is a kind of into
Air port circle, can reduce reflux, promote fan efficiency.
Second technical problem to be solved by this invention is to provide the centrifugal blower that a kind of application has above-mentioned air inlet mouth circle.
The present invention solves technical solution used by above-mentioned first technical problem are as follows: a kind of air inlet mouth circle, including water conservancy diversion
Portion, the diversion division include radial diversion division, the radial outside of the radial direction diversion division being projected as circle and having in the axial direction
First center of circle, the radially inner side of the radial direction diversion division being projected as circle and having second center of circle in the axial direction, feature exists
In: first center of circle and second center of circle are not overlapped.
For convenient for air-flow is imported into blower interior, the radial direction diversion division axially on first direction it is arc-shaped prominent
Out, the radially inner side of the radial diversion division extends to the second direction on axially and forms axial diversion portion, and described the
One direction and second direction are opposite.
For convenient for enter the wind mouth circle installation, further include mounting portion, the mounting portion in a ring, it is described radial direction diversion division diameter
It is connect outward with the radially inner side of mounting portion.
It preferably, is the variable cross-section shape for ensuring to enter the wind mouth circle, on radial section, the mounting portion has radial outside
Endpoint, the radial direction diversion division have radial outside endpoint be, radially inner side endpoint, the axial diversion portion has far from radial
The endpoint of diversion division is circular arc between the radial outside endpoint and radially inner side endpoint of the radial direction diversion division, the circular arc tool
Have a third center of circle, the third center of circle, radial diversion division radially inner side endpoint, the second center of circle three point on a straight line, the circular arc with
By the tangent with axial parallel straight line of radial diversion division radially inner side endpoint.
The present invention solves technical solution used by above-mentioned second technical problem are as follows: a kind of application have as described above into
The centrifugal blower of air port circle, it is characterised in that: including spiral case and the impeller being arranged in spiral case, be formed with air inlet on the spiral case
Mouthful and air outlet, air inlet mouth circle setting is in air inlet, it is characterised in that: air inlet forward, the axis horizontal of impeller
When extending from the front to the back, the angle between line relatively horizontal orientation between second center of circle and first center of circle is 0~
60 °, and second center of circle is located at side of first center of circle far from air outlet.
Preferably, to enter impeller convenient for guidance air-flow, the outer diameter of the radial direction diversion division is Di, the outer diameter of the impeller
For D2, two outer diameters meet following relationship: Di=(0.94-0.99) D2, and wherein D2 is the outer diameter of impeller.
Preferably, to enter impeller convenient for guidance air-flow, the internal diameter of the radial direction diversion division is Do, and Do=(0.80-
0.86)D2。
Preferably, to reach complete machine air quantity and efficiency most preferably, the distance between first center of circle and second center of circle
For L, offset distance ratio ε=L/D2, ε=0.016.
Compared with the prior art, the advantages of the present invention are as follows: it is constituted and making the inside and outside center of circle for entering the wind mouth circle eccentric
The air inlet mouth circle of variable cross-section, can make the vortex of air inlet more stable, and intensity is bigger, the position of vortex and distribution to
Impeller center is mobile, so that flow velocity becomes larger inside spiral case, velocity gradient becomes smaller, and flow increases in entire condition range, efficiency
Reach full working scope covering in entire condition range, is highly improved.
Detailed description of the invention
Fig. 1 is the schematic diagram on the centrifugal blower of the embodiment of the present invention；
Fig. 2 is the axis projection schematic diagram of the centrifugal blower of the embodiment of the present invention；
Fig. 3 is the schematic perspective view of the air inlet mouth circle of the embodiment of the present invention；
Fig. 4 is the axis projection schematic diagram of the air inlet mouth circle of the embodiment of the present invention；
Fig. 5 is the radial cross section of the air inlet mouth circle of the embodiment of the present invention；
Fig. 6 is the centrifugal blower section A PIV test result schematic diagram of the prior art；
Fig. 7 is the prior art and centrifugal blower of the invention in low flow rate condition lower section A PIV test result schematic diagram；
Fig. 8 is that the prior art and centrifugal blower of the invention show in best efficiency point operating condition lower section A PIV test result
It is intended to；
Fig. 9 is the prior art and centrifugal blower of the invention in big flow operating condition lower section A PIV test result schematic diagram；
Figure 10 is the import gross section streamlines distribution of the prior art and centrifugal blower of the invention under best efficiency point operating condition
Schematic diagram.
Specific embodiment
The present invention will be described in further detail below with reference to the embodiments of the drawings.
Referring to FIG. 1 to FIG. 5, a kind of centrifugal blower is formed on spiral case 1 including spiral case 1 and the impeller 2 being arranged in spiral case 1
There are air inlet 11 and air outlet 12, air inlet mouth circle 3 is provided at air inlet 11.For ease of description, hereinafter, axially referring to impeller
2 axial direction radially refers to the radial direction of impeller 2 or the radial parallel direction with impeller 2.
Entering the wind mouth circle 3 includes mounting portion 31 and diversion division 32, and mounting portion 31 is annular in shape, for will entirely enter the wind mouth circle 3
It is mounted on spiral case 1.Diversion division 32 includes radial diversion division 321 and axial diversion portion 322, and the radial setting of diversion division 321 is being pacified
In dress portion 31, radial its radial outside of diversion division 321 connect with the radially inner side of mounting portion 31 and from radial outside it is radial to
Interior extension, in addition, radial diversion division 321 (is in the present embodiment, towards outside centrifugal blower also along the first direction in axial direction
Direction) arc-shaped protrusion.The radially inner side of radial diversion division 321 to the second direction on axially (in the present embodiment,
It is opposite with first direction for towards the direction in centrifugal blower) extend and forms above-mentioned axial diversion portion 322.
The radial outside of radial diversion division 321 impeller shaft it is upward be projected as justifying, there is the first center of circle O, this first
Center of circle O is on the axis of impeller；The radially inner side of radial diversion division 321 in the upward projection of impeller shaft be also it is round, have second
Center of circle O ', second center of circle O ' and the first center of circle O be not be overlapped.By this eccentric manner, so that the radial section of air inlet mouth circle 3
For variable cross-section.
Air inlet 11 forward, the axis horizontal of impeller 2 extend from the front to the back in the case where, with by the first center of circle O, with
Axially vertical horizontal line is X-axis, and direction of the X-axis using air outlet 12 with respect to the first center of circle O passes through first as positive direction
The vertical line of center of circle O is Y-axis, and positive direction is upward.The second center of circle O ' is located at the third quadrant of the coordinate system, i.e. two circles as a result,
Heart line OO ' is 180~240 °, preferably 240 °.
Enter the wind the outer diameter of mouth circle 3, i.e., the outer diameter of radial diversion division 321 is Di, Di=(0.94-0.99) D2, and wherein D2 is
The outer diameter of impeller 2.D2=256mm in the present embodiment, Di=254mm.The internal diameter Do=(0.80-0.86) of radial diversion division 321
D2, the present embodiment Do=210mm.The distance between first center of circle O and the second center of circle O ', i.e. eccentricity are L, offset distance ratio ε=L/
D2。
Referring to fig. 2, using impeller center O as origin, the first center of circle O to the distance between the second center of circle O ' L and two o'clock line
It is shown respectively at a distance from the air inlet bias of mouth circle 3 with the angle theta of reference axis and direction.Its outlet is caused in view of its offset is excessive
When exporting close with impeller 2, the flow at 2 shroud of impeller will be increased and leaked.Therefore, L successively takes 4mm, 8mm and 12mm；Definition
Polar coordinate system rotate angle, θ be eccentric angle, θ=60 ° i, i=0,1,2,3,4,5.Different eccentricity L and eccentric angle θ combination determines
18 kinds of schemes.The relative change rate for defining flow and efficiency carries out optimizing to central coordinate of circle, to small flow Qmin=7.768m3/
Min, peak efficiency Qbep=13.229m3/ min and big flow Qmax=21.837m3The phase of/min tri- operating condition down-offs and efficiency
Change rate is weighted and averaged, founding mathematical models carry out numerical value optimizing:
In formula: i is Protocol Numbers, i=0,1,2,3,4,5；N is operating condition number, respectively Qmin, Qbep, Qmax。
Calculate initial guess by numerical value: the second center of circle O ' is in θ=240 °, the orientation ε=0.016 (L=4mm), fume-exhausting
Machine overall performance promotes maximum, air quantity Q raising 1.33%, efficiency eta promotion 5.2%.
That is, the angle between line relatively horizontal orientation between the second center of circle O ' and the first center of circle O be 0~
60 °, and the second center of circle O ' is located at the first side of the center of circle O far from air outlet 12.
It is radial cross section referring to Fig. 5, the radial outside endpoint in 31 section of mounting portion is a1, radial diversion division 321
The radial outside endpoint in section is a2, and the radially inner side endpoint in radial 321 section of diversion division is a, and axial diversion portion 322 is far from diameter
It is a3 to the endpoint of diversion division 321.It is between the radial outside endpoint a2 and radially inner side endpoint a in radial 321 section of diversion division
Circular arc, with third center of circle Oa, third center of circle Oa, 321 section of radial diversion division radially inner side endpoint a, the second center of circle O '
Three point on a straight line, circular arc a2a are tangent with axial parallel straight line with the radially inner side endpoint a's by 321 section of radial diversion division.
Preferably, Oa2=127mm；The length L1=14mm of O ' a=108.68mm, OO '=6.6mm, line segment a1a2, the length of line segment aa3
Spend L2=5.4mm.
Variable cross-section air inlet mouth circle 3 of the invention to the improvement of range hood inlet flow as shown in fig. 7~fig. 9, it is left
Figure is the prior art, and right figure is the present invention, it is seen that in three operating conditions, fan inlet region A has knot similar with PIV test
The unsteady vortex of structure, air-flow convergence enter the orientation of fan inlet at θ=240 °.The vortex of eccentric rear fan import is more
Stablize, intensity is bigger, and the position of vortex and distribution are mobile to impeller center.As shown in Figure 10, in best efficiency point operating condition,
Stagnation region is mobile to volute outlet at eccentric rear fan volute tongue S4.The distribution of volute tongue downstream S5 vortex tape becomes smaller, through-flow feelings
Condition improves.Flow velocity becomes larger inside spiral case, and velocity gradient becomes smaller.Compared with prior art, variable cross-section enters the wind mouth circle, in entire operating condition
Flow increases in range, air quantity maximum lift 9%；Efficiency reaches full working scope covering, efficiency maximum lift in entire condition range
8%.
Claims (8)
1. a kind of air inlet mouth circle, including diversion division (32), the diversion division (32) includes radial diversion division (321), the radial direction
The radial outside of diversion division (321) in the axial direction be projected as circle and have first center of circle (O), it is described radial direction diversion division (32)
Radially inner side in the axial direction be projected as circle and have second center of circle (O '), it is characterised in that: first center of circle (O) and
(O ') is not overlapped in second center of circle.
2. air inlet mouth circle according to claim 1, it is characterised in that: it is described radial direction diversion division (321) axially on
The arc-shaped protrusion of first direction, the radially inner side of the radial direction diversion division (321) extend to the second direction on axially and
It is formed axial diversion portion (322), the first direction and second direction are opposite.
3. air inlet mouth circle according to claim 2, it is characterised in that: it further include mounting portion (31), the mounting portion (31)
In a ring, the radial outside of the radial diversion division (321) is connect with the radially inner side of mounting portion (31).
4. air inlet mouth circle according to claim 2, it is characterised in that: on radial section, the mounting portion (31) has
Radial outside endpoint (a1), it is (a2), radially inner side endpoint (a), institute that the radial direction diversion division (321), which has radial outside endpoint,
Stating axial diversion portion (322) has the endpoint (a3) far from radial diversion division (321), the radial direction of the radial direction diversion division (321)
It is circular arc (a2a) that the circular arc has the third center of circle (Oa) between outer point (a2) and radially inner side endpoint (a), described the
Three centers of circle (Oa), radial diversion division (321) radially inner side endpoint (a), second center of circle (O ') three point on a straight line, the circular arc
(a2a) and by the tangent with axial parallel straight line of radial diversion division (321) radially inner side endpoint (a).
5. the centrifugal blower that a kind of application has air inlet circle as described in any one of claims 1 to 4, it is characterised in that: packet
The impeller (2) of spiral case (1) and setting in spiral case (1) is included, is formed with air inlet (11) and air outlet on the spiral case (1)
(12), the air inlet mouth circle is arranged at air inlet (11), it is characterised in that: air inlet (11) forward, the axis of impeller (2)
When level extends from the front to the back, between the line relatively horizontal orientation between second center of circle (O ') and first center of circle (O)
Angle is 0~60 °, and second center of circle (O ') is located at side of first center of circle (O) far from air outlet (12).
6. centrifugal blower according to claim 5, it is characterised in that: the outer diameter of the radial direction diversion division (321) is Di, institute
The outer diameter for stating impeller (2) is D2, and two outer diameters meet following relationship: Di=(0.94-0.99) D2, and wherein D2 is impeller (2)
Outer diameter.
7. centrifugal blower according to claim 6, it is characterised in that: the internal diameter of the radial direction diversion division (321) is Do, and
And Do=(0.80-0.86) D2.
8. centrifugal blower according to claim 6, it is characterised in that: first center of circle (O) and second center of circle (O ') it
Between distance be L, offset distance ratio ε=L/D2, ε=0.016.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910463522.8A CN110145481B (en) | 2019-05-30 | 2019-05-30 | Air inlet ring and centrifugal fan with same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910463522.8A CN110145481B (en) | 2019-05-30 | 2019-05-30 | Air inlet ring and centrifugal fan with same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110145481A true CN110145481A (en) | 2019-08-20 |
| CN110145481B CN110145481B (en) | 2021-01-19 |
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ID=67593703
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910463522.8A Active CN110145481B (en) | 2019-05-30 | 2019-05-30 | Air inlet ring and centrifugal fan with same |
Country Status (1)
| Country | Link |
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| CN (1) | CN110145481B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022062043A1 (en) * | 2020-09-25 | 2022-03-31 | 佛山市顺德区美的洗涤电器制造有限公司 | Centrifugal fan and range hood |
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| US2951630A (en) * | 1957-08-30 | 1960-09-06 | Westinghouse Electric Corp | Centrifugal fans |
| DE3715833A1 (en) * | 1987-05-12 | 1988-11-24 | Bosch Siemens Hausgeraete | Radial-flow centrifugal pump and the use of such a pump in a washing machine |
| CN102162467A (en) * | 2011-05-12 | 2011-08-24 | 上海英格索兰压缩机有限公司 | Centrifugal fan device eccentrically arranged by adopting arc enclosure and impeller |
| CN202065244U (en) * | 2011-04-01 | 2011-12-07 | 如皋市凯瑞纺织机械有限公司 | Casing of cotton suction fan for spinning frame |
| CN104595242A (en) * | 2014-12-29 | 2015-05-06 | 宁波方太厨具有限公司 | Air inlet adjustable centrifugal fan |
| CN109237579A (en) * | 2018-10-29 | 2019-01-18 | 杭州老板电器股份有限公司 | Low-noise fan and kitchen ventilator |
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2019
- 2019-05-30 CN CN201910463522.8A patent/CN110145481B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2951630A (en) * | 1957-08-30 | 1960-09-06 | Westinghouse Electric Corp | Centrifugal fans |
| DE3715833A1 (en) * | 1987-05-12 | 1988-11-24 | Bosch Siemens Hausgeraete | Radial-flow centrifugal pump and the use of such a pump in a washing machine |
| CN202065244U (en) * | 2011-04-01 | 2011-12-07 | 如皋市凯瑞纺织机械有限公司 | Casing of cotton suction fan for spinning frame |
| CN102162467A (en) * | 2011-05-12 | 2011-08-24 | 上海英格索兰压缩机有限公司 | Centrifugal fan device eccentrically arranged by adopting arc enclosure and impeller |
| CN104595242A (en) * | 2014-12-29 | 2015-05-06 | 宁波方太厨具有限公司 | Air inlet adjustable centrifugal fan |
| CN109237579A (en) * | 2018-10-29 | 2019-01-18 | 杭州老板电器股份有限公司 | Low-noise fan and kitchen ventilator |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022062043A1 (en) * | 2020-09-25 | 2022-03-31 | 佛山市顺德区美的洗涤电器制造有限公司 | Centrifugal fan and range hood |
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| Publication number | Publication date |
|---|---|
| CN110145481B (en) | 2021-01-19 |
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