CN102720700B - The blade of axial fan and axial flow fan for air conditioner - Google Patents

Abstract

The invention provides a blade of an axial flow fan. When the blade is cut by the first cylindrical surface coaxial with the fan axis determined by H%=0.80 and r=80mm, the blade has a characteristic cross section satisfying the following parameter conditions: α ₁ =0 °, α ₂ =177.7°, β=38.6°, b=174.2, P _1x =27.16, P _1y =96.24, P _1z =-9.65, P _2x =-99.95, P _2y =3.08, P _2z =-83.92; When H%=0.57, r=80, H%=0.44, r=80, H%=0.36, r=80, H%=0.31, r=80, the above parameter values change accordingly when the blades are intercepted on the cylindrical surface, The unmarked unit is mm. Axial fans for air conditioning are also available. Through the best parameter matching, the air volume of the fan is increased, the noise is reduced, and the cost performance is improved.

Description

Blades of axial fan and axial fan for air conditioner

technical field

The invention belongs to the technical field of air conditioning, and in particular relates to a blade of an axial flow fan for air conditioning and an axial flow fan for air conditioning.

Background technique

In the design process of axial flow fans used in ventilation and ventilation devices such as air conditioners, the design of the blade installation angle directly affects the aerodynamic performance of the blades, and therefore has an important impact on the air volume of the fan. The radial bending angle and forward-sweeping bending angle of the blade not only affect the air volume, but also have an important impact on the aerodynamic noise. At present, it is often difficult to achieve the best parameter matching in the fan design process, resulting in the problems of insufficient air volume and high noise in the old airfoil fan. With the development of computer technology and computational fluid dynamics (Computational Fluid Dynamics, referred to as CFD), and its advantages of short cycle, low cost, effective analysis of various influencing factors and quantitative flow field parameters, etc. It is a brand-new method in the field of design and development, which can accurately predict the aerodynamic performance and acoustic characteristics of the fan in the design stage, provide a basis for the parameter optimization and structural design of the fan, and reduce the cost and work of the test quantity, shorten the R&D cycle, and improve the economic benefits of the enterprise.

Today, the energy efficiency ratio of ventilation equipment such as air conditioners is getting higher and higher. The efficiency of the existing axial flow fans is generally low, which cannot meet the requirements of high air volume, high air pressure, and low noise. There is an urgent need for improvement. The purpose of the present invention is to achieve a new breakthrough in the performance of the whole machine, energy saving and noise reduction.

For the design of open low-pressure axial flow fans, the air volume and air pressure of the fan are generally increased by designing element-level airfoils, adjusting the airflow attack angle of different cross-sectional airfoils, the curvature, radian, and number of blades, etc. Aerodynamic noise of the fan. At present, the air volume of the open low-pressure axial flow fan is insufficient and the noise is high, which urgently needs to be solved.

Contents of the invention

The invention provides a blade of an axial flow fan and an axial flow fan for an air conditioner, which can solve the problems in the prior art that the air volume and pressure of the axial flow fan are insufficient and the noise is high due to unreasonable blade design.

In order to solve the above-mentioned technical problems, on the one hand, the present invention provides a blade of an axial flow fan: it includes a plurality of superimposed characteristic sections, and the contour line of the characteristic sections is surrounded by an inner arc curve and a back arc curve. When the blade is intercepted by the first cylindrical surface coaxial with the fan axis determined by H%=0.80, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =0°, α ₂ =177.7°, β=38.6°, b=174.2mm, P _1x =27.16mm, P _1y =96.24mm, P _1z =-9.65mm, P _2x =-99.95mm, P _2y =3.08mm, P _2z =-83.92mm;

When the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.57, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =3.8°, α ₂ =162.0°, β=35.0°, b=236.0mm, P _1x =25.37mm, P _1y =137.68mm, P _1z =8.46mm, P _2x =-139.99mm, P _2y =-0.27mm, P _2z =-88.09mm;

When the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.44, r=80mm, the blade has a characteristic section satisfying the following parameter conditions: α ₁ =10.1°, α ₂ =149.5°, β=30.3°, b=301.7mm, P _1x =15.00mm, P _1y =179.36mm, P _1z =21.57mm, P _2x =-178.86mm, P _2y =-20.25mm, P _2z =-95.15mm;

When the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.36, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =16.7°, α ₂ =145.6°, β=26.5°, b=367.6mm, P _1x =-4.79mm, P _1y =219.95mm, P _1z =30.65mm, P _2x =-214.11mm, P _2y =-50.57mm, P _2z =-103.9mm;

When the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.31, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =24.0°, α ₂ =142.8°, β=23.4°, b=435.2mm, P _1x =-35.1mm, P _1y =257.62mm, P _1z =36.70mm, P _2x =-242.58mm, P _2y =-93.56mm, P _2z =-115.2mm;

The relevant parameters are defined as follows:

H%: the ratio of r to R;

r: radius of the outer cylindrical surface of the impeller circular hub;

R: The radius of a different cylindrical surface concentric with the inscribed cylindrical surface of the hub is R;

L ₁ : The line connecting the midpoints of the blade cross-sections cut by different cylindrical surfaces with a radius R that is concentric with the inscribed cylindrical surface of the hub;

L ₂ : the line connecting the middle point Q of the blade root chord line and the center point O of the fan;

L ₃ : The line connecting the arc midpoint N and the fan center point O;

α ₁ : the angle between L ₂ and L ₃ , called the radial bending angle of the blade;

L ₄ : the tangent along the curve of the front edge at the intersection of the front edge of the fan and the cylindrical surface corresponding to R;

L ₅ : the line connecting the tangent point P and the midline point O through L ₄ ;

α ₂ : the included angle between L ₄ and L ₅ , called the blade forward-swept bending angle;

β: The included angle between the reference plane perpendicular to the fan axis and the chord line of the cross-section of the blade cut by different cylindrical surfaces with a radius R that is concentric with the cylindrical surface of the hub, called the blade installation angle;

Points P ₁ , P ₂ : refer to the leading edge and trailing edge points of the blade on the intersecting profile line between cylindrical surfaces with different radii R and the pressure surface of the blade, and the coordinates are expressed as P ₁ (P _1x , P _1y , P _1z ), P ₂ (P _2x , P _2y , P _2z );

b: The line connecting the intersection of the cylindrical surface with radius R and the leading edge and trailing edge of the blade is called the chord length of the airfoil;

xy plane, z axis: based on the spatial rectangular coordinate system, the origin of the coordinates is the center point of the motor shaft hole on the blade root side, and the xy plane is a plane passing through the origin and perpendicular to the fan axis; the origin is connected to the first cylindrical surface and the blade The line connecting the intersections of the trailing edge lines is the positive direction of the x-axis, and the direction perpendicular to the xy plane from the pressure surface to the suction surface is the z-axis direction.

Further, when the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.67, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =1.5°, α ₂ = 171.6°, β=37.1°, b=204.7mm, P _1x =27.27mm, P _1y =116.86mm, P _1z =0.10mm, P _2x =-119.95mm, P _2y =3.45mm, P _2z =-85.62mm .

Further, when the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.5, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =6.8°, α ₂ = 153.2°, β=32.6°, b=268.5mm, P _1x =21.31mm, P _1y =158.58mm, P _1z =15.56mm, P _2x =-159.78mm, P _2y =-8.39mm, P _2z =-91.29 mm.

Further, when the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.4, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =13.4°, α ₂ = 149.2°, β=28.3°, b=334.8mm, P _1x =6.34mm, P _1y =199.89mm, P _1z =26.62mm, P _2x =-197.02mm, P _2y =-34.39mm, P _2z =-99.33 mm.

Further, when the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.33, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =20.2°, α ₂ = 138.2°, β=24.8°, b=400.8mm, P _1x =-18.6mm, P _1y =239.28mm, P _1z =33.95mm, P _2x =-229.58mm, P _2y =-69.93mm, P _2z =- 109.1mm.

Further, when the blade is cut on a cylindrical surface coaxial with the fan axis determined by H%=0.29, r=80mm, the blade has a characteristic cross-section satisfying the following parameter conditions: α ₁ =26.6°, α ₂ = 140.8°, β=21.9°, b=439.3mm, P _1x =-46.5mm, P _1y =265.12mm, P _1z =35.93mm, P _2x =-263.49mm, P _2y =-94.72mm, P _2z =- 117.7mm.

Still further, there is a continuous smooth transition between every two adjacent characteristic sections.

Wherein, the error of H% is within ±1; the error of α ₁ , α ₂ , β is within ±1°; the r, b, P _1x , P _1y , P _1z , P _2x , P _2y , The error of P _2z is within ±1mm.

Preferably, the blade material is reinforced polypropylene.

On the other hand, the present invention also provides an axial flow fan for air conditioning, all the blades of the fan adopt the blades described in the present invention.

The invention mainly solves the problems of low working efficiency, high noise and high overall weight of the open low-pressure axial flow fan used in the external unit of the air conditioner and the ventilation device.

The blade airfoil and element-level stacking method obtained by optimal parameter matching can achieve the purpose of increasing fan air volume, improving efficiency, and reducing noise. The invention forms the specific shape rule of the blade profile by performing optimal parameter matching on multiple characteristic sections of the blade.

The blades are made by injection molding process. The material of the blade is preferably reinforced PP, and can also be made of other materials.

The hub of the axial flow fan of the present invention is circular, but no matter the shape of the fan hub is circular or triangular or other arbitrary shapes, and the different changes of the ribs of the hub, the airfoil and profile of the blade defined by the characteristic section of the present invention It is also equivalent to the blade of the present invention.

Compared with prior art, advantage and positive effect of the present invention are:

1. The work efficiency of the fan is higher, which meets the requirements of high air volume, high air pressure and low noise;

2. On the premise of improving the performance of the fan blade, the average wall thickness of the fan blade is thinner, and the component cost is reduced;

3. Application of blade material Enhanced PP can improve the physical performance of the fan.

The present invention designs a reasonable element-level airfoil by combining computational fluid dynamics (CFD) simulation analysis and experimental data analysis, and adjusts the curvature, radian, and inclination of the blade to improve the performance of the fan and meet the requirements of high efficiency and low noise. .

The axial flow fan of the present invention obtains the best parameter matching by improving the element-level airfoil and the airfoil stacking method, improves the air volume and air pressure of the fan, reduces noise, has high work efficiency, and is very cost-effective.

Description of drawings

Fig. 1 is the top view of the axial flow fan adopting the blade of the present invention, shows some structural parameters in order to define the characteristic section of blade in the figure;

Fig. 2 is another view of the axial flow fan adopting the blade of the present invention, showing 10 characteristic sections of one of the blades, and parameters b, β;

Fig. 3 is a front view of one of the characteristic sections of the blade, showing the pressure surface, the suction surface, and the positions of two points P ₁ , P ₂ used to define the characteristic section;

Fig. 4 is a schematic view of blades superimposed by different characteristic sections viewed from the top of the blade;

Fig. 5 is a schematic diagram of a blade superimposed by different characteristic sections viewed from the root of the blade;

Fig. 6 is a three-dimensional forming diagram of the axial flow fan of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figures 1-5, the blade of the axial fan according to the present invention is a special-shaped body formed by superimposing a plurality of characteristic sections, and the contour curve of the characteristic section (as shown in Figure 3) is formed by the pressure surface curve A closed curve surrounded by the suction surface curve. The characteristic section of the blade is defined by the parameters shown in Table 1, which lists 10 characteristic sections and their corresponding parameters.

Table 1: 10 characteristic sections of the blade and related parameters for determining the characteristic sections

(unmarked unit: mm)

Combined with Figure 1-3, the relevant parameters in Table 1 are defined as follows:

H%: the ratio of r to R;

r: radius of the outer cylindrical surface of the impeller circular hub, as shown in Figure 1;

R: The radius of a different cylindrical surface concentric with the inscribed cylindrical surface of the hub is R, as shown in Figure 1;

L ₁ : the connection line between the midpoints of the circular arcs of the cross-section of the blade cut by different cylindrical surfaces with a radius R that is concentric with the inscribed cylindrical surface of the hub, as shown in Figure 1;

L ₂ : the line connecting the middle point Q of the blade root chord line and the center point O of the fan, as shown in Figure 1;

L ₃ : The line connecting the arc midpoint N and the fan center point O, as shown in Figure 1;

α ₁ : The included angle between L ₂ and L ₃ is called the radial bending angle of the blade, as shown in Figure 1;

L ₄ : the tangent line along the curve of the front edge at the intersection of the front edge of the fan and the cylindrical surface corresponding to R, as shown in Figure 1;

L ₅ : the line connecting the tangent point P and the midline point O through L ₄ , as shown in Figure 1;

α ₂ : The included angle between L ₄ and L ₅ is called the forward-swept bending angle of the blade, as shown in Figure 1;

β: The angle between the reference plane perpendicular to the axis of the fan and the chord line of the cross-section of the blade cut by different cylindrical surfaces with a radius R concentric with the cylindrical surface of the hub is called the blade installation angle, as shown in Figure 2;

Points P ₁ , P ₂ : refer to the leading edge and trailing edge points of the blade on the intersecting profile line between cylindrical surfaces with different radii R and the pressure surface of the blade, and the coordinates are expressed as P ₁ (P _1x , P _1y , P _1z ), P ₂ (P _2x , P _2y , P _2z ), as shown in Figure 3;

b: The line connecting the intersection of the cylindrical surface with radius R and the leading edge and trailing edge of the blade is called the airfoil chord length, the leading edge 1, trailing edge 2, pressure surface 3, and suction surface 4 of the blade, as shown in Figures 2 and 3 shown;

xy plane, z axis: based on the spatial rectangular coordinate system, the origin of the coordinates is the center point of the motor shaft hole on the blade root side, and the xy plane is a plane that passes through the origin and is perpendicular to the fan axis; the origin and the first cylindrical surface (that is, Table 1 The line connecting the intersection of the cylindrical surface where the characteristic section 1 is located) and the trailing edge line of the blade is the positive direction of the x-axis, and the direction perpendicular to the xy plane from the pressure surface to the suction surface is the z-axis direction. In FIG. 1 , the x-axis direction is horizontal to the right, the y-axis direction is vertically upward, and the z-axis direction is perpendicular to the paper and pointing toward the reader (x, y, z axes are not shown).

Taking the characteristic section numbered 1 as an example, the data in Table 1 are further explained as follows: On the first cylindrical surface coaxial with the fan axis determined by H%=0.80, r=80mm (that is, the above-mentioned first cylindrical surface ) when cutting the blade, the blade has a characteristic cross section satisfying the following parameter conditions: α ₁ =0°, α ₂ =177.7°, β=38.6°, b=174.2mm, P _1x =27.16mm, P _1y =96.24mm, P _1z =-9.65mm, P _2x =-99.95mm, P _2y =3.08mm, P _2z =-83.92mm, the characteristic section can be uniquely determined according to the above parameters, the parameters of other numbered characteristic sections are similar to this, no longer repeat.

Can determine 10 characteristic sections according to the parameter in table 1, but just can obtain the blade of the present invention according to characteristic section 1, characteristic section 3, characteristic section 5, characteristic section 7, characteristic section 9; In order to further optimize blade, can Increase the characteristic section 2 to determine the blade of the present invention; for further optimization, you can increase the characteristic section 4 to determine the blade of the present invention; you can also increase the characteristic section 6 to determine the blade of the present invention; you can also continue to increase the characteristic section 8 to determine The blade of the present invention; to continue, the characteristic section 10 can also be added to further optimize the blade of the present invention. Moreover, there is a continuous smooth transition between every two adjacent feature sections.

Among them, the parameters shown in Table 1 are only the most preferred values, each parameter value is allowed to have errors, and the error of H% is within ±1; the errors of the α ₁ , α ₂ , and β are within ±1° ; The error of said r, b, P _1x , P _1y , P _1z , P _2x , P _2y , P _2z is within ±1mm.

The blade material is reinforced polypropylene (PP).

On the other hand, the present invention also provides an axial flow fan for air conditioning, all the blades of the fan adopt the blades described in the present invention.

The technical effects of the present invention are described in detail by the following experimental data.

Table 2 airfoil fan of the present invention compares with existing airfoil fan experimental data

Wherein the airfoil fan of the present invention and the existing airfoil fan are fans with three blades. According to the data comparison in Table 2, it can be seen that the air-conditioning axial flow fan adopting the blade of the present invention has a large air volume and low noise.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention to other forms. Any skilled person who is familiar with this profession may use the technical content disclosed above to change or modify the equivalent of equivalent changes. Example. However, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belong to the protection scope of the technical solution of the present invention.

Claims (5)

1., a kind of blade of axial fan, comprise multiple characteristic cross-section coincided, the profile molded line of described characteristic cross-section is the closed curve surrounded by inner arc curve and back of the body arc curve, it is characterized in that:

Determine with H%=0.80, r=80mm intercept described blade with the first cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=0 °, α ₂=177.7 °, β=38.6 °, b=174.2mm, P _1x=27.16mm, P _1y=96.24mm, P _1z=-9.65mm, P _2x=-99.95mm, P _2y=3.08mm, P _2z=-83.92mm;

Determine with H%=0.57, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=3.8 °, α ₂=162.0 °, β=35.0 °, b=236.0mm, P _1x=25.37mm, P _1y=137.68mm, P _1z=8.46mm, P _2x=-139.99mm, P _2y=-0.27mm, P _2z=-88.09mm;

Determine with H%=0.44, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=10.1 °, α ₂=149.5 °, β=30.3 °, b=301.7mm, P _1x=15.00mm, P _1y=179.36mm, P _1z=21.57mm, P _2x=-178.86mm, P _2y=-20.25mm, P _2z=-95.15mm;

Determine with H%=0.36, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=16.7 °, α ₂=145.6 °, β=26.5 °, b=367.6mm, P _1x=-4.79mm, P _1y=219.95mm, P _1z=30.65mm, P _2x=-214.11mm, P _2y=-50.57mm, P _2z=-103.9mm;

Determine with H%=0.31, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=24.0 °, α ₂=142.8 °, β=23.4 °, b=435.2mm, P _1x=-35.1mm, P _1y=257.62mm, P _1z=36.70mm, P _2x=-242.58mm, P _2y=-93.56mm, P _2z=-115.2mm;

Relevant parameter is defined as follows:

The ratio of H%:r and R;

R: impeller circular hub external cylindrical surface radius;

R: the radius of the different cylndrical surface concentric from wheel hub incircle cylinder is R;

L ₁: the line of the arcuate midway point of the leaf cross-section that the different cylndrical surface that the radius concentric from wheel hub incircle cylinder is R intercept;

L ₂: the line of blade root mid-chord Q and fan center's point O;

L ₃: the line of arcuate midway point N and fan center's point O;

α ₁: L ₂with L ₃between angle, be called blade radial bending angle;

L ₄: the fan leading edge cylndrical surface point of intersection corresponding with R is along leading edge curve near tangent;

L ₅: pass through L ₄the line of point of contact P and centerline O;

α ₂: L ₄with L ₅between angle, be called blade sweepforward bending angle;

β: the angle of the string of a musical instrument of the leaf cross-section intercepted with the different cylndrical surface being R by the radius concentric with wheel hub cylndrical surface from the datum plane of fan axes normal, is called blade angle;

Point P ₁, P ₂: refer to that radius is different cylndrical surface molded line upper blade crossing with the blade pressure surface leading edge of R and trailing edge point, coordinate is expressed as P ₁(P _1x, P _1y, P _1z), P ₂(P _2x, P _2y, P _2z);

B: radius is the cylndrical surface of R and the line of blade inlet edge and trailing edge intersection point, is called aerofoil profile chord length;

Xy plane, z-axis: based on rectangular coordinate system in space, true origin is blade root side motor axis hole central point, and xy plane is with through described initial point and perpendicular to the plane of fan axis; With initial point and described first cylndrical surface and trailing edge line intersection point line for x-axis postive direction, to point to the direction of suction surface for z-axis direction perpendicular to described xy plane from pressure side;

Determine with H%=0.67, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=1.5 °, α ₂=171.6 °, β=37.1 °, b=204.7mm, P _1x=27.27mm, P _1y=116.86mm, P _1z=0.10mm, P _2x=-119.95mm, P _2y=3.45mm, P _2z=-85.62mm;

Determine with H%=0.5, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=6.8 °, α ₂=153.2 °, β=32.6 °, b=268.5mm, P _1x=21.31mm, P _1y=158.58mm, P _1z=15.56mm, P _2x=-159.78mm, P _2y=-8.39mm, P _2z=-91.29mm;

Determine with H%=0.4, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=13.4 °, α ₂=149.2 °, β=28.3 °, b=334.8mm, P _1x=6.34mm, P _1y=199.89mm, P _1z=26.62mm, P _2x=-197.02mm, P _2y=-34.39mm, P _2z=-99.33mm;

Determine with H%=0.33, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=20.2 °, α ₂=138.2 °, β=24.8 °, b=400.8mm, P _1x=-18.6mm, P _1y=239.28mm, P _1z=33.95mm, P _2x=-229.58mm, P _2y=-69.93mm, P _2z=-109.1mm;

Determine with H%=0.29, r=80mm intercept described blade with the cylndrical surface of fan axis coaxle time, described blade has the characteristic cross-section of satisfied following Parameter Conditions: α ₁=26.6 °, α ₂=140.8 °, β=21.9 °, b=439.3mm, P _1x=-46.5mm, P _1y=265.12mm, P _1z=35.93mm, P _2x=-263.49mm, P _2y=-94.72mm, P _2z=-117.7mm.

2. the blade of axial fan according to claim 1, is characterized in that: be continuous and derivable transition between adjacent every two characteristic cross-sections.

3. the blade of axial fan according to claim 1, is characterized in that: the error of described H% is in ± 1; Described α ₁, α ₂, β error in ± 1 °; Described r, b, P _1x, P _1y, P _1z, P _2x, P _2y, P _2zerror in ± 1mm.

4. the blade of the axial fan according to Claims 2 or 3, is characterized in that: described blade material adopts Reinforced Polypropylene.

5. an axial flow fan for air conditioner, is characterized in that: all blades of described fan all adopt blade described in aforementioned arbitrary claim.