CN204082659U - A kind of centrifugal blower of range hood - Google Patents
A kind of centrifugal blower of range hood Download PDFInfo
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- CN204082659U CN204082659U CN201420440977.0U CN201420440977U CN204082659U CN 204082659 U CN204082659 U CN 204082659U CN 201420440977 U CN201420440977 U CN 201420440977U CN 204082659 U CN204082659 U CN 204082659U
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- circular arc
- blade
- impeller
- range hood
- centrifugal blower
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Abstract
The utility model discloses a kind of centrifugal blower of range hood, comprise spiral case and be arranged on the impeller in spiral case, described impeller comprises multiple blade, the molded line of described blade comprise be smoothly connected be positioned at the first circular arc of ingress and be positioned at second circular arc in outlet port, the radius of described first circular arc is R
1, central angle is α
1, the radius of the second circular arc is R
2, central angle is α
2, it is characterized in that, the radii ratio of described first circular arc and the second circular arc is 3.5≤R
2/ R
1≤ 4, the central angle of described first circular arc is 85 °≤α
1≤ 90 °.Select vane type line two sections of circular arcs more reasonably radius, central angle parameter, make the long and narrow degree of the shrinkage degree at blade exit place and blade larger, impeller outlet speed is larger, leaf road inside vortex is less, better to adapt to the applied environment of range hood, thus make oil smoke more easily throw away impeller, and the eddy current of blower interior is less.
Description
Technical field
The utility model relates to a kind of range hood, especially a kind of centrifugal blower of range hood.
Background technique
Range hood has become one of machine for kitchen use equipment indispensable in Modern Family, and conventional range hood is provided with flow blower casing usually on exhaust fume collecting hood, is provided with the centrifugal blower be made up of the motor of spiral case, impeller and drives impeller in flow blower casing.
At present, the blade of the impeller of the centrifugal blower of conventional multiple-airfoil type is generally single arc-shaped structure, it is single that circular arc has compact structure, pressure coefficient is high, flow coefficient is large and low noise advantages, is widely used in the occasions such as many air interchangers, electronic equipment and air-conditioning system.But due to the impeller of multi-wing centrifugal fan, its relative width is larger, cause inlet air flow skewness vertically.The pressure pulsation of multi-wing centrifugal fan impeller internal, Jet wake structure, boundary layer separation, backflow and spiral case in secondary flow etc. its aerodynamic characteristic and noise properties are had a significant impact.Blade surface velocity distribution form is also most important for aeroperformance quality, and a large amount of tests shows, improves vane type line, and the relation of adjust flux and vane inlet flow angle preferably, tail district and flow separation can be reduced to a great extent.
As application number a kind of forward direction, centrifugal multiblade formula ventilator disclosed in the Chinese patent of 01236951.9, external rotor electric machine is provided with in casing, the wind wheel that outer rotor motor driven is made up of multiple fan blade, the shape of cross section of fan blade is made up of R1 and the R2 circular arc of two different radiis, the angle theta 2 of angle theta 1, the R2 circular arc of R1 circular arc, on wind wheel, the diameter of fan blade outlet air end rotary motion trace is D2, the diameter of air intake rotary motion trace is D1, and limits the relation between each parameter, and for example application number a kind of centrifugal blower disclosed in the Chinese patent application of 20120026433.5, comprise spiral case and the impeller be made up of multiple blade being positioned at spiral case, vane type line is two-dimentional bicircular arcs mechanism, bicircular arcs bending direction is contrary, be that 730 ~ 750mm place is smoothly connected at radius R c, starting point and the terminal of vane type line are, doing with the tangent line angle of circle Rc at tie point is the skew lines of 57 °, the circular arc that radius is 417 ~ 422mm and 688 ~ 695mm is done respectively on the skew lines of these tie point both sides, two circular arcs and impeller enter, the intersection point of outlet diameter is respectively starting point and the terminal of vane type line.
Above-mentioned centrifugal blower, can reduce the area and intensity of vortex, Ye Dao outlet port effectively, shows good aerodynamic characteristics and low noise characteristic, can raise the efficiency and reduce noise.But itself and be not suitable for range hood; this is due to the more concerned smooth degree that flows at Ye Daozhong of oil smoke in range hood; be not contaminated by smoke to protect impeller as much as possible and improve impeller life; require that oil smoke is smooth and easy in Ye Daozhong flowing, be disposablely as much as possible thrown out of impeller.Existing bicircular arcs vane type line, a large amount of backflows and whirlpool is there is between blade passage, the pressure side of Ye Daozhong is larger than suction surface pressure, due to oil smoke than the density of air and coefficient of viscosity larger, oil smoke is easier to be flowed to suction surface by pressure side and forms whirlpool backflow, and especially in outlet port, air-flow gets lodged in outlet port and goes out not go, both added flow losses, also made oil smoke pollution impeller.
Model utility content
Technical problem to be solved in the utility model is for above-mentioned prior art Problems existing, provides a kind of centrifugal blower improving mobile performance, reduce the range hood of flow separation.
The utility model solves the problems of the technologies described above adopted technological scheme: a kind of centrifugal blower of range hood, comprise spiral case and be arranged on the impeller in spiral case, described impeller comprises multiple blade, the molded line of described blade comprise be smoothly connected be positioned at the first circular arc of ingress and be positioned at second circular arc in outlet port, the radius of described first circular arc is R
1, central angle is α
1, the radius of the second circular arc is R
2, central angle is α
2, it is characterized in that, the radii ratio of described first circular arc and the second circular arc is 3.5≤R
2/ R
1≤ 4, the central angle of described first circular arc is 85 °≤α
1≤ 90 °.
Preferably, the radii ratio of described first circular arc and the second circular arc is R
2/ R
1=4, the central angle of described first circular arc is α
1=90 °, now the long and narrow degree of the shrinkage degree at blade exit place and blade is larger, and impeller outlet speed is larger, and leaf road inside vortex is less, and oil smoke more easily throws away impeller, and the eddy current of blower interior is less.
In order to reduce the impact of inlet air flow for leaf road, and reduce the eddy current of outlet, the entrance established angle of described blade is β
1, the exit installation angle of described blade is β
2, and 52 °≤β
1≤ 90 °, 12 °≤β
2≤ 25 °.
In order to make impeller outlet dynamic pressure more can change static pressure into, overcoming the pressure of the common conduit of kitchen ventilator, in the end of described blade, forming hypotenuse by inside blade inlet lateral, in the middle of blade with certain angular slope.
For the effect of the congestion of the multi-wing centrifugal fan inlet air flow that is improved, impeller outlet dynamic pressure is made more to change static pressure into, flowing is made better to adapt to enter the turning process of Ye Daoqian, and make overall flow uniform and stable to a certain extent, the projected length of hypotenuse on blade height direction of described blade is h, the height of described blade integral is H, and h/H=0.05 ~ 0.2.Preferred, h=8.7mm, h/H=0.067, the conversion ratio of now dynamic pressure and static pressure reaches optimum.
Described Casing width is B, and impeller outlet width is b
2, the ratio 1.1≤B/b of described Casing width and impeller outlet width
2≤ 1.3, reduce B/b
2impact loss when air-flow enters spiral case can be reduced, in order to make to flow out spiral case more swimmingly by the air-flow in many circular arcs leaf road, reducing the pollution of oil smoke for spiral case, extending the time in working life of spiral case.
For making Ye Daonei air-flow close to uniformly accelerated motion further, the point of contact radius of described first circular arc and the second circular arc is R
3, radius is R
3blade tangent line and centrifugal blower to rotate reciprocal angle be β
3, and 30 °≤β
3≤ 120 °.
Compared with prior art, the utility model has the advantage of: select vane type line two sections of circular arcs more reasonably radius, central angle parameter, make the long and narrow degree of the shrinkage degree at blade exit place and blade larger, impeller outlet speed is larger, leaf road inside vortex is less, better to adapt to the applied environment of range hood, thus make oil smoke more easily throw away impeller, and the eddy current of blower interior is less; And select rational blade inlet established angle and exit installation angle, the impact of inlet air flow for leaf road can be reduced, and reduce the eddy current of outlet; Cut sth. askew at the two ends of blade, make impeller outlet dynamic pressure more can change static pressure into, overcome the pressure of the common conduit of kitchen ventilator, to improve fan performance; Reduce the ratio of Casing width and impeller outlet width, make to flow out spiral case more swimmingly by the air-flow in many circular arcs leaf road, reduce the pollution of oil smoke for spiral case, extend the time in working life of spiral case.
Accompanying drawing explanation
Fig. 1 is the inner smooth distributed simulation schematic diagram in prior art many circular arcs leaf road;
Fig. 2 is the sectional view of centrifugal blower of the present utility model;
Fig. 3 is the structural representation of the impeller of centrifugal blower of the present utility model;
Fig. 4 is vane type line schematic diagram of the present utility model;
Fig. 5 is even acceleration leaf road sectional view;
Fig. 6 is that leaf of the present utility model says opening vortex district geometric parameter schematic diagram;
Fig. 7 is the contrast schematic diagram in the leaf road of leaf road of the present utility model and prior art;
Fig. 8 is the structural representation of blade of the present utility model;
Fig. 9 is the inner smooth distributed simulation schematic diagram in leaf road of the present utility model.
Embodiment
Below in conjunction with accompanying drawing, embodiment is described in further detail the utility model.
See Fig. 2 and Fig. 3, a kind of centrifugal blower of range hood, the impeller 2 comprising spiral case 1 and be arranged in spiral case 1.
Multiple blades 23 that impeller 2 comprises end ring 21, wheel disc 22 and is arranged between end ring 21 and wheel disc 22.Blade 23 molded line is the multi-section circular arc of many diameters, and Ye Daonei air-flow can be made to realize uniformly accelerated motion, considerably reduces the degree that Ye Daonei produces flow separation or reduces flow separation.
See Fig. 4, the molded line C1 of blade 23 comprises the bending direction of the second circular arc 232, two sections of circular arcs in the first circular arc 231 of the ingress of the air intake that two sections are smoothly connected and the outlet port of air-out unanimously, wherein, and R
3be two sections of circular arc point of contact radiuses, β
3for radius R
3blade 23 tangent line and centrifugal blower rotate reciprocal angle, preferably, 30 °≤β
3≤ 120 °.R
1and R
2be respectively the radius of the first circular arc 231 and the second circular arc 232, P
1and P
2be respectively the first circular arc 231 and the second circular arc 232 the center of circle, and α
1and α
2be respectively the central angle of the first circular arc 231 and the second circular arc 232, β
1and β
2be respectively the entrance established angle of the first circular arc 231 and the exit installation angle of the second circular arc 232.Arrow in Fig. 4 represents sense of rotation.
See Fig. 5, this is the leaf road sectional view that a kind of bicircular arcs vane type line is formed, space (the region F between circular arc ge and circular arc ajb
1) be with the uniform shrinkage part of blade 23 working surface for reference line mapping posterior lobe road, form the even acceleration leaf road of blower fan, region F
2the non-uniform shrinkage part in Shi Ye road.Compared with the leaf road of single circular arc profile, the non-uniform shrinkage part area F in many circular arc profiles leaf road
2area reduces, and it is long and narrow that shape becomes, and the strength of vortex thus betiding this position weakens to some extent, eddy current loss reduces to some extent.Again because blade 23 radius of arc of Ye Dao ingress is comparatively large, blade 23 established angle is moderate, thus the impact loss of Ye Dao ingress air-flow reduces, while making the efficiency of blower fan obviously increase, the increasing of Ye Dao outlet port blade 23 radius of arc makes again vortex, Ye Dao outlet port become long and narrow eddy current circular diameter reduction leaf and says the eigenvalue decline of opening vortex district.The noise figure of leafy blower fan is obviously declined.
When leaf road molded line is close to even acceleration leaf road molded line, fan noise obviously declines, and efficiency significantly improves.
In order to make the even acceleration distance of Ye Daonei strengthen, the central angle alpha of the first circular arc 231
1select maximum value, the radius ratio R of two sections of circular arcs as far as possible
2/ R
1also choose maximum value, because leaf road is longer and narrower, Ye Dao more tends towards stability in flow field as far as possible.But leaf road neither be more long and narrow better, because the area of contact increase between air-flow and leaf road can cause friction loss to increase, thus causes centrifugal blower decrease in efficiency.According to repeatedly calculating and test the central angle alpha that we find the first circular arc 231
190 ° can not be greater than, R
2/ R
1can not be greater than 4, otherwise centrifugal blower efficiency can decline.
Further flow field analysis shows, what select when blade 23 is the central angle alpha of the first circular arc 231
1be 90 °, R
2/ R
1during many circular arcs when being 4, the shrinkage degree in blade 23 outlet port and the long and narrow degree of blade are larger, and impeller 2 outlet velocity is larger, and leaf road inside vortex is less, and oil smoke more easily throws away impeller, and the eddy current of blower interior is less.Pass through simulation calculation, see Fig. 9, a small amount of vortex is had in blade path near snail tongue, when design discharge and large discharge, interior flow field is very stable, and air-flow is smooth, can't see vortex, and in impeller 2 outlet port, air-flow deflection is greater than other leaf models, therefore this leaf model more can improve pressure; See Fig. 1, and for the central angle alpha of the first circular arc 231
1be less than 85 °, R
2/ R
1be less than 3.5 or first central angle alpha of circular arc 231
1be greater than 90 °, R
2/ R
1be greater than the blower fan of many curved blades of 4, its blade path interior flow field there will be vortex in various degree, and the streamline in Ye Dao outlet port is intensive not, also just means that a part of flow loss is inner in Liao Ye road, causes the pollution of oil smoke for leaf road further.
Under 1080rpm speed conditions, the central angle alpha of the first circular arc 231
1be 90 degree, R
2/ R
1when=4, compared to general many curved blades, air quantity brings up to 18.3m3/min by 15.4m3/min, and maximum static pressure brings up to 363Pa by 321Pa, and maximal efficiency brings up to 35% by 26%.
Again see Fig. 5, leaf road Elongation characterization value is a geometric parameter that can be similar to proportionate relationship between the length in reflection leaf road and width, and that is the approximative value of leaf road Elongation is leaf road Elongation characterization value, and it is defined as:
wherein, l is leaf road Elongation characterization value, S
1for leaf road section upper blade non-working surface arc length (circular arc ahb section arc length), S
2for leaf road section upper blade working surface arc length (circular arc eg section arc length), L
1for the chord length between entrance incircle two point of contact, leaf road, L
2for the chord length between outlet incircle two point of contact, leaf road, d is non-even acceleration region F on foliage leaf road section
2on maximum inscribed circle diameter.
Because between it and real leaf road Elongation, error is little, but should using conveniently, thus having more practicability when calculating leaf road flowing field stability.This characterization value Yue great Ze Ye road is longer and narrower, Ye Dao more tends towards stability in flow field, simultaneously because the area of contact between air-flow and leaf road increases) friction loss increases, thus fan efficiency will decline to some extent, so in leaf road Elongation characterization value sampling process, the stability in Ye Dao flow field can be maintained, keep blower fan to have higher operational efficiency again.
And when the radius of vane type line, the value of central angle adopt scope of the present utility model, can find that leaf road of the present utility model is longer and narrower, L
2less, entrance first circular arc 231 is bending close to 90 °, and d is also less, it can thus be appreciated that leaf road Elongation characterization value is comparatively large, and leaf road smoothness tends towards stability, and blower fan has higher efficiency.
See Fig. 6, show the research of entrance established angle, due to the High Rotation Speed of impeller 2, air-flow is not enter Ye Dao along the direction perpendicular to leaf road entrance, but has certain impact to the pressure side of blade.When the entrance established angle of blade 23 is larger, the impulse ratio of air-flow to blade 23 is stronger, and energy loss is comparatively large, and less entrance established angle ratio is easier to guide air flow direction, reduces air-flow to the impact of pressure side.When inside and outside footpath is identical, stagger angle β
1less, blade 23 length is longer, and the area that blade 23 is used for doing work is larger.Less entrance established angle β
1, the central angle alpha of the first circular arc 231 can be made
1larger, and the central angle alpha of the first larger circular arc 231
1be conducive to improving fan performance.Therefore, in the design method of many curved blades, in order to reduce the impact of inlet air flow for leaf road, and reducing the eddy current of outlet, selecting through test of many times, preferably, 52 °≤β
1≤ 90 °, 12 °≤β
2≤ 25 °, and most preferred, β
1be 60 °, β
2it is 20 °.
In sum, preferably, the central angle 85 °≤α of the first circular arc 231
1≤ 90 °, 3.5≤R
2/ R
1≤ 4.Also efficiency is not lost, the central angle alpha of the first circular arc 231 while improving fan performance
1optimum value be 90 °, and R
2/ R
1optimum value be 4, now fan efficiency brings up to 29.5% by 22%, air quantity improve 36%, maximum static pressure improve 45%.
See Fig. 7, can find out from figure, in various many curved blades, the shape of leaf road front half part is substantially close; For general many curved blades molded line C2, import is larger.And in the utility model preferred embodiment, the length of the molded line C1 of blade 23 is longer compared with C2, the degree of crook in the middle part of blade 23 is a little larger, and the leaf road that C1 is formed is larger than the shrinkage degree of C2.And the actual acting part of C1 will be longer than C2, and the size of impeller acting is relevant with acting area, and known employing blade of the present utility model 23 makes blower fan have higher operational efficiency.
See Fig. 8, export dynamic pressure to make impeller 2 and more can change static pressure into, overcome the pressure of the common conduit of kitchen ventilator, preferably, blade 23 uses upper and lower symmetry to cut sth. askew blade, namely in the end of blade 23, hypotenuse is formed by inside lateral, blade 23 ingress, in the middle of blade 23 with certain angular slope.
The vane inlet place not doing to cut sth. askew is comparatively narrow, air-flow import reduce structure throttling action under accelerate, mass air flow crosses impeller central authorities and bottom in turning flow process, less air-flow is passed through from impeller top area, such pressure gradient is formed just uneven, cause top air turbulence, and then form eddy current, this is also the key factor affecting fan performance.And in fact cut sth. askew be exactly the congestion improving multi-wing centrifugal fan inlet air flow, its exit velocity and the speed be diffused in spiral case differ larger, impeller 2 can be made to export dynamic pressure and more to change static pressure into, flowing is made better to adapt to enter the turning process of Ye Daoqian, and make overall flow uniform and stable to a certain extent, thus improve the performance of blower fan.
The height (projected length namely in blade 23 short transverse) of the right angle side that the hypotenuse of blade 23 is relative is h, and the height of blade 23 entirety is H, then preferably, h/H=0.05 ~ 0.2, optimally, cut into slices as right angle side h is the right-angled triangle of 8.7mm, h/H=0.067.
Again see Fig. 2, because spiral case 1 width is B, impeller 2 exit width is b
2, two width ratio B/b
2performance for centrifugal blower has larger impact, reduces B/b
2impact loss when air-flow enters spiral case can being reduced, in order to make to flow out spiral case more swimmingly by the air-flow in many circular arcs leaf road, reducing the pollution of oil smoke for spiral case, extend the time in working life of spiral case, the utility model uses the width ratio of less impeller outlet, more preferably, and 1.1≤B/b
2≤ 1.3, optimally B/b
2=1.1.
Claims (8)
1. the centrifugal blower of a range hood, comprise spiral case (1) and be arranged on the impeller (2) in spiral case (1), described impeller (2) comprises multiple blade (23), the molded line of described blade (23) comprise be smoothly connected be positioned at first circular arc (231) of ingress and be positioned at second circular arc (232) in outlet port, the radius of described first circular arc (231) is R
1, central angle is α
1, the radius of the second circular arc (232) is R
2, central angle is α
2, it is characterized in that, the radii ratio of described first circular arc (231) and the second circular arc (232) is 3.5≤R
2/ R
1≤ 4, the central angle of described first circular arc (231) is 85 °≤α
1≤ 90 °.
2. the centrifugal blower of range hood as claimed in claim 1, it is characterized in that, the radii ratio of described first circular arc (231) and the second circular arc (232) is R
2/ R
1=4, the central angle of described first circular arc (231) is α
1=90 °.
3. the centrifugal blower of range hood as claimed in claim 1 or 2, it is characterized in that, the entrance established angle of described blade (23) is β
1, the exit installation angle of described blade (23) is β
2, and 52 °≤β
1≤ 90 °, 12 °≤β
2≤ 25 °.
4. the centrifugal blower of range hood as claimed in claim 1, it is characterized in that, in the end of described blade (23), form hypotenuse by inside blade (23) lateral, ingress, in the middle of blade (23) with certain angular slope.
5. the centrifugal blower of range hood as claimed in claim 4, it is characterized in that, the projected length of hypotenuse in blade (23) short transverse of described blade (23) is h, and the height of described blade (23) entirety is H, and h/H=0.05 ~ 0.2.
6. the centrifugal blower of range hood as claimed in claim 5, is characterized in that, h=8.7mm, h/H=0.067.
7. the centrifugal blower of range hood as claimed in claim 1, it is characterized in that, described spiral case (1) width is B, and impeller (2) exit width is b
2, the ratio 1.1≤B/b of described spiral case (1) width and impeller (2) exit width
2≤ 1.3.
8. the centrifugal blower of range hood as claimed in claim 1, it is characterized in that, the point of contact radius of described first circular arc (231) and the second circular arc (232) is R
3, radius is R
3blade (23) tangent line and centrifugal blower to rotate reciprocal angle be β
3, and 30 °≤β
3≤ 120 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420440977.0U CN204082659U (en) | 2014-08-06 | 2014-08-06 | A kind of centrifugal blower of range hood |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420440977.0U CN204082659U (en) | 2014-08-06 | 2014-08-06 | A kind of centrifugal blower of range hood |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204082659U true CN204082659U (en) | 2015-01-07 |
Family
ID=52175382
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420440977.0U Withdrawn - After Issue CN204082659U (en) | 2014-08-06 | 2014-08-06 | A kind of centrifugal blower of range hood |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204082659U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104165158A (en) * | 2014-08-06 | 2014-11-26 | 宁波方太厨具有限公司 | Centrifugal fan of extractor hood |
| WO2017133370A1 (en) * | 2016-02-01 | 2017-08-10 | 宁波方太厨具有限公司 | Fan impeller and fan using fan impeller |
-
2014
- 2014-08-06 CN CN201420440977.0U patent/CN204082659U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104165158A (en) * | 2014-08-06 | 2014-11-26 | 宁波方太厨具有限公司 | Centrifugal fan of extractor hood |
| WO2017133370A1 (en) * | 2016-02-01 | 2017-08-10 | 宁波方太厨具有限公司 | Fan impeller and fan using fan impeller |
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| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20150107 Effective date of abandoning: 20160921 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |