CN202091255U

CN202091255U - Axial fan

Info

Publication number: CN202091255U
Application number: CN2011201998252U
Authority: CN
Inventors: 刘中杰; 龙斌华; 刘利娜; 曹锋
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2011-06-14
Filing date: 2011-06-14
Publication date: 2011-12-28
Anticipated expiration: 2021-06-14

Abstract

The utility model discloses an axial fan, comprising a wheel hub and a plurality of blades disposed on the periphery of the wheel hub, wherein the front edge of each blade is provided with a thickening part, the thickening part is extended from the root of the wheel hub to the outer edge of each blade, and the thickening part is extended along with an equivalent element arc from the front edge of each blade to the back edge of each blade so as to set length; and each blade is bent towards a suction surface or a pressure surface, so that the suction surface or the pressure surface of each blade forms a curved surface. When the axial fan rotates, the vibration and the vortex of the blades can be lightened, the noise generated by the axial fan can be reduced, and the whole performance of the axial fan can be improved.

Description

A kind of axial fan

Technical field

The utility model relates to the axial-flow windwheel technical field, relates to a kind of axial fan in particular.

Background technique

In air conditioner outdoor machine and some ventilation equipment, extensively adopt axial fan as the air-supply parts.Axial fan comprises wheel hub and is arranged on several blades on the wheel hub, and the design of blade has directly influenced the complete machine performance of outdoor air conditioner and blowing device.

When the wheel hub of existing axial fan rotated, the blade of axial fan can produce the comparatively strong vibration of trembling along with wheel hub rotates, and causes the vibration of whole axial fan, and then causes the judder of complete machine, produces bigger influence of noise.Simultaneously, existing axial fan blade is comparatively smooth, when axial flow rotates, the pressure side of blade and suction surface can produce bigger pressure difference, and owing to the existence of pressure difference, the air-flow of pressure side can reflux to the suction surface that is in low-pressure state at the blade edge place, cause the gas disorder, produce boundary layer and separate and vortex phenomenon, make the noise of fan raise, and then influence machine performance and working life.

As seen, existing axial fan is because blade trembles and the blade vortex phenomenon can produce big noise, influence the performance of axial fan, therefore, how to solve in the axial fan rotation process, because the noise problem that blade trembles and vortex phenomenon causes is the technical problem that those skilled in the art press for solution.

The model utility content

In view of this, the utility model provides a kind of axial fan, in the axial fan rotation process, can alleviate that blade trembles and the blade vortex phenomenon, reduces the noise that axial fan produces, and improves axial fan complete machine performance.

For achieving the above object, the utility model provides a kind of axial fan, comprise wheel hub and be arranged on some blades on the described wheel hub periphery, each blade bi-side on the flow direction vertically is respectively pressure side and suction surface, and the leading edge of described blade is provided with the thickening part;

Extend to the outer rim of described blade from the root of described wheel hub described thickening part, and from the leading edge of described blade to described vane trailing edge along waiting primitive camber line extension preseting length;

Described blade makes the suction surface of described blade and/or pressure side form curved surface to described suction surface bending.

Preferably, the boundary curve that is positioned at the boundary curve of described pressure side on the described blade cross section radially and/or is positioned at described suction surface is the curve towards the suction surface bending, and up the time, described boundary curve is higher than the end of described boundary curve near the wheel hub root near an end of outer rim at the suction surface of described blade.

Preferably, described thickening part is arranged on the pressure side and/or the suction surface of the leading edge of described blade.

Preferably, on the pressure side and suction surface that are arranged on described leading edge of described thickening part symmetry.

Preferably, the drop shadow curve of radially camber line on first projection plane of described vane trailing edge is made up of first line segment and second line segment, and described first projection plane is the plane perpendicular to described axial fan running shaft;

Described first line segment is the broken line that the outer rim from the root of described wheel hub towards described blade is extended, and the wrap direction of each break of this broken line is all identical, and described wrap direction deviates from the leading edge of described blade;

Described second line segment is the curve of starting point for the end with the close described outer rim of described first line segment, and the bending direction of described curve is identical with the wrap direction of described broken line.

Described first line segment is the straight line that the outer rim from the root of described wheel hub towards described blade is extended;

Described second line segment is the curve of starting point for the end with the close described outer rim of described first line segment, and the bending direction of described curve deviates from the leading edge of described blade.

Described first line segment is the curve that the outer rim from the root of described wheel hub towards described blade is extended, and the bending direction of described curve deviates from the leading edge of described blade;

Preferably, when the drop shadow curve's length on first projection plane of described vane trailing edge was La, the length of described first line segment was 0.6～0.8La.

Preferably, first circular arc that the outer cause of described blade links to each other successively, second circular arc and three-arc are formed, and wherein, described first circular arc is a starting point with the leading edge of blade;

The radius of described first circular arc and described three-arc is all less than the radius of described second circular arc.

Preferably, the outer rim of the thickness of described thickening part from the wheel hub root towards described blade radially reduces gradually.

Preferably, from the leading edge of described blade on described vane trailing edge direction, the thickness of described thickening part is along waiting primitive camber line to diminish gradually.

Preferably, the maximum ga(u)ge T of described thickening part _MaxRatio T with the maximum radius R of the outer rim of described blade _Max/ R=0.051～0.06, the minimum thickness T of described thickening part _MinRatio T with the maximum radius R of the outer rim of described blade _Min/ R=0.016～0.03.

Preferably, described thickening part is along waiting primitive camber line to extend preseting length, and described preseting length is for setting arc length L1, L1 ∝ Ra ⁿ, n 〉=4, Ra is the pairing radius of described setting arc length L1, and ratio L1/R=0.1～0.2 of described setting arc length L1 and the maximum radius R of blade outer rim.

Preferably, on described blade cross section radially, the boundary curve of described pressure side and/or the boundary curve of described suction surface are the second-degree parabola that opening makes progress.

Preferably, on described blade cross section radially, the radius that the symmetry center of the boundary curve of described pressure side and/or the second-degree parabola that boundary curve became of described suction surface is positioned at the described wheel hub of distance is on the camber line of Rx, ratio Rx/R=0.6～0.7 of described radius R x and blade outer rim maximum radius R.

Preferably, the equation of the second-degree parabola that boundary curve became of the boundary curve of described pressure side and/or described suction surface is:

y＝-0.0748x ²-0.9855x+2.842；

Wherein, the x axle is the direction of extending to the blade outer rim along this wheel hub root, and the y axle is the coordinate axes with the wheel hub shaft parallel; The x value representation is a true origin with the boundary curve of pressure side and/or suction surface and the intersection point of wheel hub in the system of coordinates that is made of described x axle and y axle, the abscissa value of the point on the boundary curve of described pressure side and suction surface; The y value representation is a true origin with the boundary curve of pressure side and/or suction surface and the intersection point of wheel hub in the system of coordinates that is made of described x axle and y axle, the ordinate value of the point on the boundary curve of described pressure side and suction surface.

Preferably, on described blade cross section radially, the curvilinear equation of the boundary curve of described pressure side and/or the boundary curve of described suction surface is:

y＝-0.0003x ⁴+0.0153x ³-0.1858x ²+0.6015x+0.3976；

y＝-0.0003x ⁴+0.0166x ³-0.2112x ²+0.7868x；

In addition, the utility model also provides another kind of axial fan, comprise wheel hub and be arranged on some blades on the described wheel hub periphery, each blade bi-side on the flow direction vertically is respectively pressure side and suction surface, and the leading edge of described blade is provided with the thickening part;

Described blade makes the pressure side of described blade form curved surface to described pressure side bending.

Preferably, the boundary curve that is positioned at the boundary curve of described pressure side on the described blade cross section radially and/or is positioned at described suction surface is the curve towards the pressure side bending, and down the time, described boundary curve is lower than the end of described boundary curve near the wheel hub root near an end of outer rim at the suction surface of described blade.

Preferably, when the drop shadow curve's length on first projection plane of described vane trailing edge was La, the length of described first line segment was 0.6La～0.8La.

Preferably, on described blade cross section radially, the boundary curve of described pressure side and/or the boundary curve of described suction surface are the second-degree parabola that Open Side Down.

y＝-0.02x ²+0.2042x-3.4697；

y＝-2×10 ^-8x ⁴+2×10 ^-6x ³-0.014x ²+0.1479x-2.1532；

Via above-mentioned technological scheme as can be known, compared with prior art, the utility model openly provides a kind of axial fan, this axial fan is provided with the thickening part in the leading edge of blade, radially extend to the outer rim of blade from the root of wheel hub this thickening part, and along with each concentric circular arc of described wheel hub on extend preseting length, in the axial fan rotation process, when under the prerequisite of same airflow to the blade inlet edge bump, owing to be provided with the thickening part at blade inlet edge, can increase the stable degree of blade, reduce the vibration of blade, thereby reduce the noise that produces in the axial fan rotation.

Simultaneously, blade is to pressure side or suction surface bending, stick up so that the blade outer rim is little, the pressure side of blade or suction surface form curved surface, when axial fan rotates, air-flow can change in the flow direction at blade outer rim place, air-flow weakens the impact force at edge, thereby has reduced the thickening degree of boundary layer, has weakened the pressure difference of blade outer rim, thereby weaken the vortex phenomenon of blade, reduce because the noise that eddy current causes.

Description of drawings

In order to be illustrated more clearly in the utility model embodiment or technological scheme of the prior art, to do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below, apparently, accompanying drawing in describing below only is embodiment of the present utility model, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to the accompanying drawing that provides.

Fig. 1 is a kind of axial fan embodiment's one of the utility model a Facad structure schematic representation;

Fig. 2 is a kind of axial fan embodiment's one of the utility model a structure schematic representation;

Fig. 3 comprises the radially perspective view of cross section curve of blade for a kind of axial fan embodiment's one of the utility model;

Fig. 4 is a kind of axial fan embodiment's one of the utility model a blade cross section curve structural representation radially;

Fig. 5 is a kind of axial fan embodiment's one of the utility model the blade schematic representation of curvilinear structures in plane coordinate system in cross section radially;

Fig. 6 is a kind of axial fan embodiment's one of the utility model the blade data analysis figure when radially the boundary curve in cross section is quadratic curve;

Fig. 7 is a kind of axial fan embodiment's one of the utility model the blade data analysis figure when radially the boundary curve in cross section is biquadratic curve;

Fig. 8 is a kind of axial fan embodiment's two of the utility model a Facad structure schematic representation;

Fig. 9 is a kind of axial fan embodiment's two of the utility model a vane trailing edge curve projection schematic representation;

Figure 10 is a kind of axial fan embodiment's three of the utility model a blade outer rim structural representation;

Figure 11 comprises the radially perspective view of cross section curve of blade for a kind of axial fan embodiment's four of the utility model;

Figure 12 is a kind of axial fan embodiment's four of the utility model the blade schematic representation of curvilinear structures in plane coordinate system in cross section radially;

Figure 13 is a kind of axial fan embodiment's four of the utility model the blade data analysis figure when radially the boundary curve in cross section is quadratic curve;

Figure 14 is a kind of axial fan embodiment's four of the utility model the blade data analysis figure when radially the boundary curve in cross section is biquadratic curve.

Embodiment

Below in conjunction with the accompanying drawing among the utility model embodiment, the technological scheme among the utility model embodiment is clearly and completely described, obviously, described embodiment only is the utility model part embodiment, rather than whole embodiments.Based on the embodiment in the utility model, those of ordinary skills are not making the every other embodiment who is obtained under the creative work prerequisite, all belong to the scope of the utility model protection.

Each blade of axial fan bi-side on the flow direction vertically is respectively pressure side and suction surface, the edge of every blade and its sense of rotation same side be leading edge, with the edge of its sense of rotation opposition side be that trailing edge, radially outer edge are outer rim, when existing axial fan rotates, because blade vibration or vortex phenomenon make outdoor air conditioner or blowing device that this axial fan is installed can produce very big noise in running.Find that by analysis the reason that produces noise in the existing axial fan rotation process mainly contains following two aspects:

At first, the leading edge of the blade of existing axial fan is thinner, and it is relatively poor that blade inlet edge is resisted the ability of airflow strikes, when axial fan rotated, after the leading edge of blade was subjected to airflow strikes, serious shake can take place, tremble in blade, and then drive the vibration of whole axial fan, produce very big noise;

Secondly, the blade face of the blade of existing axial fan is comparatively smooth, thereby cause in the axial fan rotation process, because gas viscosity, make gas along the middle boundary layer that generates of flowing of blade, cause that the blade radial distribution of exit velocities is inhomogeneous, the pressure difference of the suction surface of blade and pressure side (front and back of blade just) is bigger, at the blade edge place because the existence of pressure difference, the air-flow of pressure side can reflux to the suction surface that is in low-pressure state, cause the gas disorder, produce boundary layer and separate and vortex phenomenon, make the noise of fan raise.

In order to reduce the noise that the axial fan rotation process produces, need take all factors into consideration above two reasons that produce noise, the utility model embodiment provides a kind of axial fan, this axial fan comprises wheel hub and several blades that are arranged on the wheel hub, the thickening part that is provided with in the leading edge of blade, this thickening part begins to extend to the blade outer rim along blade radial from the wheel hub root of the leading edge of blade, extend to vane trailing edge from the leading edge of blade this thickening part, and along etc. the primitive camber line extend preseting length.By set up the stability that the thickening part can strengthen blade inlet edge at blade inlet edge, increase the ability that blade is resisted gas shock, reduced the vibration of blade.

Simultaneously, for less blade vortex phenomenon, shape structure to blade changes, blade is to the suction surface bending, making that the blade outer rim is little sticks up, make the blade face (being suction surface) of face of blade form curved surface C (Fig. 3 illustrates), when axial fan rotates, air-flow can change in the flow direction at blade outer rim place, air-flow weakens the impact force at edge, thereby has reduced the thickening degree of boundary layer, weakens the pressure difference (outer rim is the boundary of suction surface and pressure side) of blade outer rim, thereby weaken the vortex phenomenon of blade, reduce because the noise that eddy current causes.

Referring to Fig. 1 and Fig. 2, be respectively a kind of axial fan embodiment's one of the utility model Facad structure schematic representation and structure schematic representation, this axial fan comprises wheel hub 1 and several blades 2 that are arranged on wheel hub 1 periphery, each blade bi-side on the flow direction vertically is respectively pressure side and suction surface, the number of blade can be set as required, can be two or more, the utility model is not limited this;

The leading edge 21 of this blade 2 be provided with thickening part 24, extend to the outer rim 23 of blade from the root 11 of wheel hub this thickening part 24; Extend to described vane trailing edge 22 from the leading edge 21 of blade this thickening part, and along waiting primitive camber line to extend the length of setting.

Wherein, waiting the primitive camber line to be meant on the blade circular arc line with the wheel hub concentric, is that on the blade one waits the primitive camber line as Fig. 1 mean camber line L, and this camber line L is one section circular arc line.That is to say, thickening part 24 along with each concentric circular arc of described wheel hub 1 on extend the length of setting; This thickening part 24 extends to blade outer rim 23 from wheel hub root 11 beginnings of the leading edge 21 of blade along blade radial;

This thickening part can be arranged on the pressure side and/or the suction surface of the leading edge of blade.That is, the thickening part can be arranged on the pressure side of the leading edge of blade separately, also can be arranged on the suction surface of the leading edge of blade separately, and perhaps pressure side and the suction surface in the leading edge of blade all is provided with the thickening part.Further, thickening part 24 can evenly be arranged on the pressure side and the suction surface of the leading edge 1 of this blade, that is to say these thickening part 24 equally distributed front and backs that are arranged on the blade inlet edge zone.

Wherein, suction surface also claims the front (Fig. 1 is the suction surface of blade, just the curved surface C among Fig. 3) of the blade of air draught face or windward side spindle wheel fan; Pressure side is also referred to as the back side (Fig. 2 is the pressure side of blade) of the blade of lee face spindle wheel fan, and after suction surface was come the wind suction, along with the rotation of blade, pressure side can be given pressure of wind, and blast is walked.

From the root 11 of wheel hub on the radial direction (longitudinal direction) of blade outer rim 21, extend from wheel hub root 11 along the outer rim 23 to blade radially this thickening part 24, the length that radially extend the thickening part can be set as required, the thickening part can extend to the outer rim 23 of blade always, can certainly radially extend the length of appointment.Wherein, radially just be meant the radial direction of trailing wheel hub root 11, shown in direction of arrow T among the figure to blade outer rim 23.

On the arc direction that has same radius on the blade (promptly, in a lateral direction), the length of setting arc length is extended in thickening part 24 along each camber line of distance wheel hub center of circle same radius from the leading edge 21 of blade, that is to say, thickening part 24 along the leading edge 21 of blade to the arc direction of trailing edge 22, on the camber line that radius is identical arbitrarily on the blade, extend the length of setting arc length, certainly, on the blade with the camber line of radius can be not yet with the center of circle of wheel hub, as long as have in a lateral direction on the camber line of radius, thickening part extension preseting length both can.

For example, referring to shown in Figure 1, thickening preseting length L1 on the camber line of radius is an example with the thickening part, figure mean camber line L is one section identical circular arc line of radius on the blade, the radius of this circular arc line is Ra, and then the thickening part extends to the thickening part from blade inlet edge the L1 length of this camber line on this camber line L.On other camber lines with radius on the blade, the bearing of trend of thickening part is identical therewith, and the length of extending on each camber line can be enjoyed setting as required.As setting the thickening part transversely at blade, the length of extending from each camber line of blade inlet edge is directly proportional with the radius of its camber line herein, that is, establish L and be on the blade arbitrarily the length with the camber line of radius, the length L 1 that extend the thickening part is a setting value for the ratio L1/L of L.

Wherein, the outer rim of the thickness of this thickening part 24 from wheel hub root 11 towards blade is along radially reducing gradually.In other words, on the direction of blade radial, the thickening part is in the thickness maximum of wheel hub root 11, and the thickness of thickening part from the wheel hub root along radially diminishing gradually.In order to reduce noise, do not increase the power consumption of blade simultaneously, concrete, the maximum ga(u)ge T of this thickening part 24 _MaxRatio T with the maximum radius R of blade outer rim _Max/ R=0.051～0.06, preferably, the maximum ga(u)ge T of this thickening part 24 _MaxRatio T with the maximum radius R of blade outer rim _Max/ R=0.052 or 0.051 or 0.06; The minimum thickness T of thickening part 24 _MinRatio T with the maximum radius R of blade outer rim _Min/ R=0.016～0.03, preferably, the minimum thickness T of thickening part 24 _MinRatio T with the maximum radius R of the outer rim of blade _Min/ R=0.016 or 0.02 or 0.03.If the camber line of the outer rim of blade 23 is the circular arc line of same radius, then maximum radius just is meant, the circular arc line radius corresponding of this blade outer rim; If the camber line of blade outer rim is made up of the circular arc line of multistage different radii, then maximum radius should be got the camber line radius corresponding of radius maximum.Setting thickening part maximum ga(u)ge and minimum thickness are in order better to guarantee the stability of blade with the ratio of outer rim maximum radius.

Further, by the leading edge 21 of blade on the direction of vane trailing edge (or claim blade trailing edge) 22 (or claiming in a lateral direction), thickening part 24 is in the thickness maximum at blade inlet edge 21 places, and the thickness of thickening part 24 along etc. the primitive camber line diminish gradually.That is to say that along on each camber line of same radius on the blade, thickening part 24 diminishes to the thickness on vane trailing edge 22 directions gradually from the leading edge 21 of blade.

More reasonable for the design that makes the thickening part, referring to Fig. 1, the thickening part is extended setting arc length L1, described setting arc length L1 ∝ Ra from the leading edge 21 of blade at the camber line L of distance wheel hub center of circle same radius (being primitive camber line L such as certain bar) ⁿ, n 〉=4, Ra is the radius of described setting arc length L1, also can be described as the radius of camber line L, and ratio L1/Ra=0.1～0.2 of described setting arc length L1 and the maximum radius R of blade outer rim, preferably, L1/Ra desirable 0.1 or 0.2 or 0.15.

This blade is to the suction surface bending, and the suction surface of blade forms curved surface, and corresponding pressure side can be curved surface, can not be curved surface also.The outer rim of blade is to the suction surface bending, make the slight perk in outer rim place of blade, look from the front of blade, blade radial is bowing, on the blade radial direction, from the radially camber line extension downwards earlier of wheel hub root, be bent upwards after downwards extending certain distance, make blade from the wheel hub root to the blade outer rim gradually to the blade suction surface bending, form the blade shape of similar cambered surface, and when blade suction surface faced up, outer rim one end of blade was higher than the end of blade near wheel hub.

Further, referring to Fig. 3, Fig. 4, blade radially is cross section B, and (wherein B1 is the cross section of the connection line of this cross section B and wheel hub, B2 is the cross section that is in an end of outer rim on the B of cross section), the boundary curve that then is positioned at the boundary curve of pressure side on the blade cross section B radially and/or is positioned at suction surface is the curve towards the suction surface bending, and when the suction surface of described blade faced up, described boundary curve was higher than the end of described boundary curve near the wheel hub root near an end of outer rim.That is to say, on blade cross section radially, the boundary curve that is positioned at suction surface is the curve towards the pressure side bending, and the suction surface of blade towards on, the boundary curve that is positioned at suction surface is higher than an end of the close wheel hub of this boundary curve near an end of outer rim, when the bending direction of the pressure side of blade is identical with this suction surface bending direction, the suction surface of blade towards on be positioned at suction surface boundary curve be higher than the end of this boundary curve near an end of outer rim near wheel hub.On the cross section of blade radial, looking in other words conj.or perhaps, the high curve in recessed two ends in the middle of the boundary curve that blade radially is positioned at pressure side and suction surface on the cross section is, and boundary curve is higher than the end of described boundary curve near the wheel hub root near an end of outer rim.In order to reduce because the noise that brings of vortex phenomenon, can be with the blade outer rim to the suction surface bending, and the curve intermediate portion of blade radial is lower, and the curve of blade radial will be higher than a end near the wheel hub root near an end of blade outer rim.

Do a cross section along blade radial, the pressure side on this cross section and the boundary curve of suction surface can be second-degree parabola, and the opening of described second-degree parabola upwards.The outer rim of blade is little curved to suction surface, simultaneously on blade 1 cross section radially, the curve that the boundary curve at the face of blade and the back side became is the higher second-degree parabola shape camber line in middle slightly recessed two ends, that is to say that the top edge curve of the radial cross section of blade and lower limb curve are second-degree parabola shape.For this blade of clearer description structure radially, do a cross section in the radial direction from the wheel hub root to the blade outer rim, referring to Fig. 4, the sectional view that obtains for radial cross section along blade, then the boundary curve in this cross section is the camber line of second-degree parabola shape, and this second-degree parabola is the parabola that opening makes progress, so the boundary curve in blade radial cross section is the slightly high parabolas in middle low two ends.Wherein, the end near wheel hub on the radial cross section of blade is an end that indicates the B1 place among the figure, and the B2 place is outer rim one end.In order to understand conveniently, can radially do a plane (if this axial fan horizontal positioned, then this plane promptly can be vertical plane) by the arbor wheel running shaft, then the projection of blade radial on this plane also is shown in Figure 4.

The second-degree parabola that boundary curve presented in this cross section is arranged in the plane coordinate system, referring to Fig. 5 and Fig. 6, the initial point of system of coordinates is to should blade radial cross section upper blade and the point of contact of wheel hub root, x (promptly, X (R)) axle is the direction of extending to the blade outer rim along this wheel hub root, the x value represents the boundary curve that is positioned at pressure side and suction surface on the cross section in the upwardly extending length of this side, y (being Y (R)) axle for the coordinate axes of wheel hub shaft parallel, the y value represents the boundary curve that is positioned at pressure side and suction surface on the cross section at the upwardly extending height of this side (postive direction), promptly, the x value representation is in the system of coordinates that is made of described x axle and y axle, with the boundary curve of pressure side and/or suction surface and the intersection point of wheel hub is true origin, the abscissa value of the point on the boundary curve of described pressure side and suction surface; The y value representation is in the system of coordinates that is made of described x axle and y axle, with the boundary curve of pressure side and/or suction surface and the intersection point of wheel hub is true origin, the ordinate value (postive direction) of the point on the boundary curve of described pressure side and suction surface, among the figure, series one is the actual edge curve of fan blade, the function curve of series two for coming out according to this actual edge curve fitting.At this coordinate plane the boundary curve in this cross section (or with this cross section on the parallel any second-degree parabola line of boundary curve of positive pressure face) is analyzed, can obtain second-degree parabola that this section edges curve become can be by formula one expression:

Y=-0.0748x ²-0.9855x+2.842 (formula one)

Further, in order to reduce vortex phenomenon, on blade cross section radially, the radius that the symmetry center of the boundary curve of pressure side and/or the second-degree parabola that boundary curve became of suction surface is positioned at the described wheel hub of distance is on the camber line of Rx, ratio Rx/R=0.6～0.7 of described radius R x and blade outer rim maximum radius R.The symmetry center of said second-degree parabola just is meant the minimum point place of second-degree parabola herein.That is to say, with blade radially do the cross section, be positioned at face of blade and/or the equal second-degree parabola of dorsal edge curve on the cross section that obtains, and the radius R x of the minimum point place camber line of second-degree parabola and the ratio of the radius of blade outer rim can be set in 0.6～0.7 the scope, determine the position of the minimum point of second-degree parabola at blade radial with this.

Need to prove, because the curve shape of a branch in the hyperbola is similar to the second-degree parabola shape, therefore, also we can say, is the curve shape of a hyp branch along the boundary curve that is positioned at the boundary curve of pressure side on the cross section of blade radial and/or is positioned at suction surface.

Certainly, the boundary curve that is positioned at the boundary curve of described pressure side on the blade cross section radially and/or is positioned at described suction surface also can be n curve about x, wherein, and 2≤n≤6.Still being example in the system of coordinates shown in Figure 5, the boundary curve in blade cross section radially also can be biquadratic curve, be the blade radially structural drawing of the biquadratic curve that boundary curve became in cross section and data analysis result (among the figure as Fig. 7, series one is the actual edge curve of fan blade, the function curve of series two for coming out according to this actual edge curve fitting), can obtain biquadratic curve that this section edges curve become can be by formula two expressions:

Y=-0.0003x ⁴+ 0.0153x ³-0.1858x ²+ 0.6015x+0.3976 (formula two)

The equation of this biquadratic curve also can be y=-0.0003x ⁴+ 0.0166x ³-0.2112x ²+ 0.7868x

Certainly n curve's equation about x can have multiple, so long as with trailing edge to the suction surface bending, looking towards blade cross section radially simultaneously, the boundary curve that is positioned at the boundary curve of described pressure side on the blade cross section radially and/or is positioned at described suction surface is the high curves in middle recessed two ends, and the vortex phenomenon that can reduce on the blade gets final product.Further, so long as with trailing edge to the suction surface bending, looking towards blade cross section radially simultaneously, the boundary curve that is positioned at described suction surface on the blade cross section radially is the high curve in middle recessed two ends (satisfying formula one or formula two or other function curve formula), be that suction surface is a curved surface, as long as can reduce the vortex phenomenon on the blade, this moment, pressure side can be curved surface, also can not be curved surface (promptly this moment, pressure side can have any shape).

The complete machine performance of axial fan is also relevant with the power consumption of fan, existing axial fan is when reducing fan noise, whether do not consider the influence that brings to the fan power consumption, the blade area of existing axial fan is very big, but effective acting area of blade is less, because blade area is big, leaf weight is bigger, has increased the power consumption of blade again simultaneously.

For when reducing blade noise, reduce the power consumption of axial fan, referring to Fig. 8 and Fig. 9, structural representation for a kind of axial fan embodiment two of the utility model, embodiment two is with embodiment one difference, increase the area of vane trailing edge 22, with the outside extending of curve of close outer rim 23 on the vane trailing edge 22, to increase the area of trailing edge near outer rim 23 places of blade.In order to increase the area of trailing edge near the blade outer edge area, the radially camber line of vane trailing edge 22 is set to be made up of first arc and second arc, and the joint of first arc and second arc is O.The drop shadow curve of radially camber line on first projection plane of vane trailing edge 22 is made up of the first line segment S1 and the second line segment S2, wherein, first projection plane is perpendicular to the plane of axial fan running shaft (when the axial-flow leaf horizontal positioned, first projection plane is the arbitrary plane that is parallel to horizontal plane); The first line segment S1 is the broken line that the outer rim 22 from the root 11 of wheel hub towards blade is extended, and the wrap direction of each break of this broken line is all identical, and wrap direction deviates from the leading edge of blade; The second line segment S2 is the curve of starting point for the end with the close outer rim of the first line segment S1, and the bending direction of curve is identical with the wrap direction of broken line.

The first line segment S1 be from wheel hub root 11 radially to the projection line segment of the camber line the tie point O on first projection plane, that is, the first camber line line segment is in the projection on first projection plane.First arc has bigger radian, this camber line steadily changes slowly, and the first line segment S1 of its drop shadow curve be the slow linear line segment of variation, and first line segment can be thought and is made up of the multistage broken line, bending is less between each broken line that links to each other, and makes the line segment S1 that wins present the line style of line-like.

The second line segment S2 is the projection of second arc on first projection plane, and the tie point O1 of the first line segment S1 and the second line segment S2, tie point O1 are the projection of tie point O on first projection plane.This second line segment is a curve, and preferred, this second line segment S2 can be parabolic shape, and this parabola is outwards expanded along the direction that deviates from leading edge, increases the area of vane trailing edge near outer edge area.

Wherein, this first line segment S1 straight line that also can extend towards the outer rim of described blade for the root of trailing wheel hub; Corresponding, the second line segment S2 is the curve of starting point for the end with the close described outer rim of the first line segment S1, the bending direction of described curve deviates from the leading edge of blade.

Certainly, the curve that the first line segment S1 also can extend towards the outer rim of blade for the root of trailing wheel hub, and the bending direction of the curve that become of the first line segment S1 deviates from the leading edge of blade; Corresponding with first line segment, the second line segment S2 is for being the curve of starting point with first line segment near an end of outer rim, and the bending direction of the curve that become of second line segment deviates from the leading edge of blade.

Concrete, the second line segment S2 can be parabola, parabolical bending direction deviates from the leading edge of blade.

Discover through the inventor, in the arbor wheel fan rotation process, the main acting zone of blade is positioned at the zone of vane trailing edge near the outer rim of blade, and the vane trailing edge of existing axial fan is a near linear, has big radian camber line, the area of whole blade is bigger, but effective acting area of blade is also little, therefore, in the present embodiment vane trailing edge is designed to be made up of first arc and second camber line, second arc, second line segment that projection obtains on first projection plane, this second line segment becomes curve, and the bending direction of curve deviates from the leading edge of blade, thereby increased the surface area of vane trailing edge, increased effective acting area of blade, when axial fan rotates near outer rim, the air output of fan blade increases, and power consumption reduces.

Further, referring to Fig. 8, the radially camber line of vane trailing edge 22 is at the long La of the drop shadow curve of horizontal plane, and the length of the first line segment S1 is 0.6～0.8La, and preferably, the length of the first line segment S1 can be 0.6La or 0.7La or 0.8La; Second line segment be curve from 0.6La or 0.7La or 0.8La to La, in other words, when the radially camber line of trailing edge 22 when the drop shadow curve head of horizontal plane is La, tie point O1 is positioned at 0.6～0.8La place, the drop shadow curve from 0.6～0.8La to La is a parabola.

Referring to Figure 10, be a kind of axial fan embodiment's three of the utility model blade outer rim structural representation, present embodiment and embodiment's one difference is, the outer rim of blade is not to be made up of the circular arc line of same radius, first circular arc C 1 that the outer cause of this blade links to each other successively, second circular arc C 2 and three-arc C3 form, first circular arc C 1 is a starting point with the leading edge of blade, and the radius of first circular arc and three-arc is all less than the radius of described second circular arc.

This first circular arc C 1 is a starting point with the leading edge of blade, and the terminal point of first circular arc C 1 is the starting point of second circular arc C 2, and the terminal point of second circular arc C 2 is the starting point of three-arc C3, and terminal point and the vane trailing edge of three-arc C3 are joined; And the radius of second circular arc C 2 is greater than the radius of arbitrary circular arc among first circular arc C 1 and the three-arc C2.If the radius of first circular arc is the radius of R1, second circular arc is that R2, three-arc radius are R3, R2＞Max (R1 then, R2), the radius maximum of second circular arc R 2, the camber line of the outer rim of blade is not that the maximum radius of blade outer rim is the second circular arc radius corresponding R2 with radius in this case.

Discover that through the inventor gap length of blade outer rim and baffle liner can influence the size of air quantity in the fan rotation process, and the gap of blade outer rim and baffle liner is more little, fan rotates easy more the meeting design requirement of air quantity that produces.The blade outer rim is made up of three sections different circular arcs of radius in the present embodiment, the radius maximum of blade outer rim intermediate portion circular arc, the two ends radius of arc is less, the gap of blade outer rim intermediate portion and baffle liner can not change like this, the air quantity that produces in the fan rotation process can not change yet, and the radius of arc at the two ends of blade outer rim diminishes, and makes the blade integral area reduce, reduce the weight of blade, and then reduced power consumption.

For when reducing blade noise, reduce the power consumption of axial fan, can also be with blade to the pressure side bending, referring to Figure 11, comprise the radially perspective view of cross section B ' curve of blade for a kind of axial fan embodiment four of the utility model, embodiment four is with embodiment one distinctive points, the outer rim of the blade among the embodiment four is to the pressure side bending, blade is to the pressure side bending, the blade outer rim is little sticks up, the pressure side of blade becomes curved surface, make the blade face (being pressure side) of vacuum side of blade form curved surface C ', when axial fan rotated, air-flow can change in the flow direction at blade outer rim place, and air-flow weakens the impact force of the outer rim of blade, thereby reduced the thickening degree of boundary layer, weaken the pressure difference (outer rim is the boundary of suction surface and pressure side) of blade outer rim, thereby weaken the vortex phenomenon of blade, reduce because the noise that eddy current causes.

The boundary curve that is positioned at the boundary curve of pressure side on the blade cross section radially and/or is positioned at described suction surface is the curve towards the pressure side bending, and down the time, described boundary curve is lower than the end of described boundary curve near the wheel hub root near an end of outer rim at the suction surface of described blade.That is to say, on blade cross section radially, the boundary curve that is positioned at pressure side is the curve towards the pressure side bending, and the pressure side of blade towards on, the boundary curve that is positioned at pressure side is higher than an end of the close wheel hub of this boundary curve near an end of outer rim, when the bending direction of the suction surface of blade is identical with this pressure side bending direction, the pressure side of blade towards on, the boundary curve that is positioned at suction surface is higher than the end of this boundary curve near wheel hub near an end of outer rim.

Preferably, on blade cross section radially, the boundary curve that is positioned at the boundary curve of pressure side and/or is positioned at suction surface is the second-degree parabola that Open Side Down.The second-degree parabola that boundary curve presented along the cross section of blade radial among this Figure 11 is arranged in the plane coordinate system, referring to Figure 12 and Figure 13, the initial point of system of coordinates is to should blade radial cross section upper blade and the point of contact of wheel hub root, x (promptly, X (R)) axle is the direction of extending to the blade outer rim along this wheel hub root, the x value represents the boundary curve that is positioned at pressure side and suction surface on the cross section in the upwardly extending length of this side, y (being Y (R)) axle for the coordinate axes of wheel hub shaft parallel, the y value represents the boundary curve that is positioned at pressure side and suction surface on the cross section at the upwardly extending height of this side (negative direction), promptly, the x value representation is in the system of coordinates that is made of described x axle and y axle, with the boundary curve of pressure side and/or suction surface and the intersection point of wheel hub is true origin, the abscissa value of the point on the boundary curve of described pressure side and suction surface; The y value representation is in the system of coordinates that is made of described x axle and y axle, with the boundary curve of pressure side and/or suction surface and the intersection point of wheel hub is true origin, the ordinate value (negative direction) of the point on the boundary curve of described pressure side and suction surface, among the figure, series one is the actual edge curve of fan blade, the function curve of series two for coming out according to this actual edge curve fitting.At this coordinate plane the boundary curve in this cross section (or with this cross section on the parallel any second-degree parabola line of boundary curve of positive pressure face) is analyzed, can obtain second-degree parabola that this section edges curve become can be by formula three expressions:

Y=-0.02x ²+ 0.2042x-3.4697 (formula three)

Further, in order to reduce vortex phenomenon, on blade cross section radially, the radius that the symmetry center of the boundary curve of pressure side and/or the second-degree parabola that boundary curve became of suction surface is positioned at the described wheel hub of distance is on the camber line of Rx, ratio Rx/R=0.6～0.7 of described radius R x and blade outer rim maximum radius R.The symmetry center of said second-degree parabola just refers to the peak place of second-degree parabola herein.That is to say, blade is radially done the cross section, being positioned at face of blade and/or dorsal edge curve on the cross section that obtains is second-degree parabola, and the radius R x of the minimum point place camber line of second-degree parabola and the ratio of the radius of blade outer rim can be set in 0.6～0.7 the scope, determine the position of the minimum point of second-degree parabola at blade radial with this.

Certainly, the boundary curve that is positioned at the boundary curve of described pressure side on the blade cross section radially and/or is positioned at described suction surface also can be n curve about x, wherein, and 2≤n≤6.Still being example in the system of coordinates shown in Figure 12, the boundary curve in blade cross section radially also can be biquadratic curve, be the blade radially structural drawing of the biquadratic curve that boundary curve became in cross section and data analysis result (among the figure as Figure 14, series one is the actual edge curve of fan blade, the function curve of series two for coming out according to this actual edge curve fitting), can obtain biquadratic curve that this section edges curve become can be by formula four expressions:

Y=-2 * 10 ^-8x ⁴+ 2 * 10 ^-6x ³-0.014x ²+ 0.1479x-2.1532 (formula four)

Certainly n curve's equation about x can have multiple, so long as with trailing edge to the pressure side bending, looking towards blade cross section radially simultaneously, the boundary curve that is positioned at the boundary curve of described pressure side on the blade cross section radially and/or is positioned at described suction surface is the low curves in middle protruding two ends, and the vortex phenomenon that can reduce on the blade gets final product.Further, so long as with trailing edge to the pressure side bending, looking towards blade cross section radially simultaneously, the boundary curve that is positioned at described pressure side on the blade cross section radially is the low curve in middle protruding two ends (satisfying formula three or formula four or other function curve formula), be that pressure side is a curved surface, as long as can reduce the vortex phenomenon on the blade, this moment, suction surface can be curved surface, also can not be curved surface (promptly this moment, pressure side can have any shape).

Under the situation of pressure side bending, also can increase the area of trailing edge at blade, the structure of trailing edge is identical with embodiment two description, does not repeat them here.

Certainly in order to increase the acting area of blade, when the outer rim of blade under the situation of pressure side bending, the outer rim of blade also can be made up of the circular arc line of different radii, the structure of blade outer rim is identical with embodiment's three descriptions, does not repeat them here.

Each embodiment adopts the mode of going forward one by one to describe in the utility model, and what each embodiment stressed all is and other embodiments' difference that identical similar part is mutually referring to getting final product between each embodiment.。

To the above-mentioned explanation of the disclosed embodiments, make related domain professional and technical personnel can realize or use the utility model.Multiple modification to these embodiments will be conspicuous concerning those skilled in the art, and defined herein General Principle can realize under the situation that does not break away from spirit or scope of the present utility model in other embodiments.Therefore, the utility model will can not be restricted to these embodiments shown in this article, but will meet and principle disclosed herein and features of novelty the wideest corresponding to scope.

Claims

1. axial fan comprises wheel hub and is arranged on some blades on the described wheel hub periphery, and each blade bi-side on the flow direction vertically is respectively pressure side and suction surface, it is characterized in that the leading edge of described blade is provided with the thickening part;

Described blade makes the suction surface of described blade form curved surface to described suction surface bending.

2. axial fan according to claim 1, it is characterized in that, the boundary curve that is positioned at the boundary curve of described pressure side on the described blade cross section radially and/or is positioned at described suction surface is the curve towards the suction surface bending, and up the time, described boundary curve is higher than the end of described boundary curve near the wheel hub root near an end of outer rim at the suction surface of described blade.

3. axial fan according to claim 1 is characterized in that, described thickening part is arranged on the pressure side and/or the suction surface of the leading edge of described blade.

4. axial fan according to claim 3 is characterized in that, on the pressure side and suction surface that are arranged on described leading edge of described thickening part symmetry.

5. axial fan according to claim 1, it is characterized in that, the drop shadow curve of radially camber line on first projection plane of described vane trailing edge is made up of first line segment and second line segment, and described first projection plane is the plane perpendicular to described axial fan running shaft;

6. axial fan according to claim 1, it is characterized in that, the drop shadow curve of radially camber line on first projection plane of described vane trailing edge is made up of first line segment and second line segment, and described first projection plane is the plane perpendicular to described axial fan running shaft;

7. axial fan according to claim 1, it is characterized in that, the drop shadow curve of radially camber line on first projection plane of described vane trailing edge is made up of first line segment and second line segment, and described first projection plane is the plane perpendicular to described axial fan running shaft;

8. according to claim 5,6 or 7 each described axial fans, it is characterized in that when the drop shadow curve's length on first projection plane of described vane trailing edge was La, the length of described first line segment was 0.6La～0.8La.

9. axial fan according to claim 1 is characterized in that, first circular arc that the outer cause of described blade links to each other successively, second circular arc and three-arc are formed, and wherein, described first circular arc is a starting point with the leading edge of blade;

10. axial fan according to claim 1 is characterized in that, the outer rim of the thickness of described thickening part from the wheel hub root towards described blade radially reduces gradually.

11. axial fan according to claim 10 is characterized in that, from the leading edge of described blade on described vane trailing edge direction, the thickness of described thickening part is along waiting primitive camber line to diminish gradually.

12. axial fan according to claim 11 is characterized in that, the maximum ga(u)ge T of described thickening part _MaxRatio T with the maximum radius R of the outer rim of described blade _Max/ R=0.051～0.06, the minimum thickness T of described thickening part _MinRatio T with the maximum radius R of the outer rim of described blade _Min/ R=0.016～0.03.

13. axial fan according to claim 1 is characterized in that, described thickening part is along waiting primitive camber line to extend preseting length, and described preseting length is for setting arc length L1, L1 ∝ Ra ⁿ, n 〉=4, Ra is the pairing radius of described setting arc length L1, and ratio L1/R=0.1～0.2 of described setting arc length L1 and the maximum radius R of blade outer rim.

14. axial fan according to claim 2 is characterized in that, on described blade cross section radially, the boundary curve of described pressure side and/or the boundary curve of described suction surface are the second-degree parabola that opening makes progress.

15. axial fan according to claim 14, it is characterized in that, on described blade cross section radially, the radius that the symmetry center of the boundary curve of described pressure side and/or the second-degree parabola that boundary curve became of described suction surface is positioned at the described wheel hub of distance is on the camber line of Rx, ratio Rx/R=0.6～0.7 of described radius R x and blade outer rim maximum radius R.

16. axial fan according to claim 14 is characterized in that, the equation of the boundary curve of described pressure side and/or the second-degree parabola that boundary curve became of described suction surface is:

y＝-0.0748x ²-0.9855x+2.842；

17. axial fan according to claim 2 is characterized in that, on described blade cross section radially, the curvilinear equation of the boundary curve of described pressure side and/or the boundary curve of described suction surface is:

y＝-0.0003x ⁴+0.0153x ³-0.1858x ²+0.6015x+0.3976；

18. axial fan according to claim 2 is characterized in that, on described blade cross section radially, the curvilinear equation of the boundary curve of described pressure side and/or the boundary curve of described suction surface is:

y＝-0.0003x ⁴+0.0166x ³-0.2112x ²+0.7868x；

19. an axial fan comprises wheel hub and is arranged on some blades on the described wheel hub periphery, each blade bi-side on the flow direction vertically is respectively pressure side and suction surface, it is characterized in that the leading edge of described blade is provided with the thickening part;

20. axial fan according to claim 19, it is characterized in that, the boundary curve that is positioned at the boundary curve of described pressure side on the described blade cross section radially and/or is positioned at described suction surface is the curve towards the pressure side bending, and down the time, described boundary curve is lower than the end of described boundary curve near the wheel hub root near an end of outer rim at the suction surface of described blade.

21. axial fan according to claim 19 is characterized in that, described thickening part is arranged on the pressure side and/or the suction surface of the leading edge of described blade.

22. axial fan according to claim 21 is characterized in that, on the pressure side and suction surface that are arranged on described leading edge of described thickening part symmetry.

23. axial fan according to claim 19, it is characterized in that, the drop shadow curve of radially camber line on first projection plane of described vane trailing edge is made up of first line segment and second line segment, and described first projection plane is the plane perpendicular to described axial fan running shaft;

24. axial fan according to claim 19, it is characterized in that, the drop shadow curve of radially camber line on first projection plane of described vane trailing edge is made up of first line segment and second line segment, and described first projection plane is the plane perpendicular to described axial fan running shaft;

25. axial fan according to claim 19, it is characterized in that, the drop shadow curve of radially camber line on first projection plane of described vane trailing edge is made up of first line segment and second line segment, and described first projection plane is the plane perpendicular to described axial fan running shaft;

26., it is characterized in that when the drop shadow curve's length on first projection plane of described vane trailing edge was La, the length of described first line segment was 0.6La～0.8La according to claim 23,24 or 25 each described axial fans.

27. axial fan according to claim 19 is characterized in that, first circular arc that the outer cause of described blade links to each other successively, second circular arc and three-arc are formed, and wherein, described first circular arc is a starting point with the leading edge of blade;

28. axial fan according to claim 19 is characterized in that, the outer rim of the thickness of described thickening part from the wheel hub root towards described blade radially reduces gradually.

29. axial fan according to claim 28 is characterized in that, from the leading edge of described blade on described vane trailing edge direction, the thickness of described thickening part is along waiting primitive camber line to diminish gradually.

30. axial fan according to claim 29 is characterized in that, the maximum ga(u)ge T of described thickening part _MaxRatio T with the maximum radius R of the outer rim of described blade _Max/ R=0.051～0.06, the minimum thickness T of described thickening part _MinRatio T with the maximum radius R of the outer rim of described blade _Min/ R=0.016～0.03.

31. axial fan according to claim 19 is characterized in that, described thickening part is along waiting primitive camber line to extend preseting length, and described preseting length is for setting arc length L1, L1 ∝ Ra ⁿ, n 〉=4, Ra is the pairing radius of described setting arc length L1, and ratio L1/R=0.1～0.2 of described setting arc length L1 and the maximum radius R of blade outer rim.

32. axial fan according to claim 20 is characterized in that, on described blade cross section radially, the boundary curve of described pressure side and/or the boundary curve of described suction surface are the second-degree parabola that Open Side Down.

33. axial fan according to claim 32, it is characterized in that, on described blade cross section radially, the radius that the symmetry center of the boundary curve of described pressure side and/or the second-degree parabola that boundary curve became of described suction surface is positioned at the described wheel hub of distance is on the camber line of Rx, ratio Rx/R=0.6～0.7 of described radius R x and blade outer rim maximum radius R.

34. axial fan according to claim 32 is characterized in that, the equation of the boundary curve of described pressure side and/or the second-degree parabola that boundary curve became of described suction surface is:

y＝-0.02x ²+0.2042x-3.4697；

35. axial fan according to claim 20 is characterized in that, on described blade cross section radially, the curvilinear equation of the boundary curve of described pressure side and/or the boundary curve of described suction surface is:

y＝-2×10 ^-8x ⁴+2×10 ^-6x ³-0.014x ²+0.1479x-2.1532；