Impeller and fan

Abstract

The embodiment of the invention provides an impeller and a draught fan, the impeller comprises a plurality of blades rotating around a rotation axis, each blade is provided with a wave crest formed by protruding from the suction side of the blade to the pressure side of the blade and a wave trough formed by sinking from the pressure side to the suction side, and the wave crest and the wave trough extend from the front edge of the blade to the tail edge of the blade; air flow channels extending from the front edge to the tail edge are respectively formed on the pressure side and the suction side of the blade; wherein the waveform of the front edge is determined by the offset amplitude of the front edge and a front edge angle curvilinear equation of the front edge angle of the impeller, and the front edge angle curvilinear equation is obtained after the original impeller is modulated through a sinusoidal modulation equation. The waveform of the trailing edge is determined by the offset amplitude of the trailing edge and a wrap angle curvilinear equation of the wrap angle of the impeller obtained by modulating the original impeller through a sinusoidal modulation equation. According to the impeller, the noise reduction effect can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of fans, and in particular to an impeller and a fan. Background Art

[0002] Various types of fans are widely used in household appliances. For example, axial fans are generally used in household appliances such as air conditioner outdoor units and fans, while centrifugal fans are used in household appliances such as fresh air blowers. Household products generally have higher requirements for noise, so reducing the low- and medium-frequency noise of fans has always been the focus of research.

[0003] In order to reduce the low- and medium-frequency noise, in the related art, there is a fan that sets the leading edge and trailing edge of the blade on the impeller into a sawtooth shape, so as to break up and separate the large vortex through the sawtooth of the leading edge and trailing edge. This impeller has a certain effect in reducing noise, but the degree of improvement in noise is limited. Summary of the invention

[0004] In view of this, the embodiments of the present application hope to provide an impeller and a fan that can improve the noise reduction effect.

[0005] To achieve the above object, an embodiment of the present application provides an impeller, comprising:

[0006] A plurality of blades rotating around a rotation axis, wherein the blades have a wave crest protruding from the suction side of the blade to the pressure side of the blade and a wave trough recessed from the pressure side to the suction side, wherein both the wave crest and the wave trough extend from the leading edge of the blade to the trailing edge of the blade, so that the blade forms an airflow channel extending from the leading edge to the trailing edge on the pressure side and the suction side, respectively; wherein the waveform of the leading edge is determined by the leading edge angle curve equation of the leading edge angle of the impeller obtained by modulating the original impeller with a sine modulation equation, and the waveform of the trailing edge is determined by the trailing edge angle curve equation of the wrap angle of the impeller obtained by modulating the original impeller with a sine modulation equation;

[0007] Among them, on the projection plane perpendicular to the rotation axis, with the projection of the rotation axis as the origin of the coordinate system, an X-axis, a Y-axis and a plurality of tangent circles with the origin of the coordinate system as the center are defined, the angle between the line between any point on the projection of the leading edge and the origin of the coordinate system and the X-axis is the leading edge angle, and the angle between the line between the intersection points of the projection of the leading edge and the projection of the trailing edge with the same tangent circle and the origin of the coordinate system is the wrap angle.

[0008] In one embodiment, a phase difference is formed between the waveform of the leading edge and the waveform of the trailing edge.

[0009] In one embodiment, the outer edge of the blade close to the rotation axis is the blade root, and the outer edge away from the rotation axis is the blade top, and from the leading edge to the trailing edge, the wave crest and the wave trough gradually deflect toward the direction close to the rotation axis.

[0010] In one embodiment, the sinusoidal modulation equation is represented by f(Q), and the leading edge angle curve equation of the impeller is Y φ2 For: Y φ2 =y φ1 +f(X), the impeller wrap angle curve equation Y θ2 For: Y θ2 =y θ1 +f(X+k);

[0011] Among them, y φ1 The leading edge angle curve equation of the original impeller is represented by y θ1 represents the wrap angle curve equation of the original impeller, X represents the Xth cutting circle of the original impeller, 1≤X≤X max , X max Indicates the maximum number of cutting circles set, X max ≥3, k represents the number of phases, and k is not equal to 0.

[0012] In one embodiment, 15≤X max ≤45; and / or, k=1.

[0013] In one embodiment, the width of each of the air flow channels is determined by the number of the cutting circles.

[0014] In one embodiment, on the projection surface where the cutting circle is located, the projection of the wave crest and the projection of the adjacent wave trough constitute a band of the waveform projection, and there are at least two cutting circles in each 1 / 2 band.

[0015] In one implementation, the sinusoidal modulation equation f(Q) is: f(Q)=A×sin(0.5×Q×π), where A represents the amplitude of the sinusoidal modulation equation.

[0016] In one implementation, -2≤A≤2, and A is not equal to zero.

[0017] In one embodiment, the offset amplitude of the leading edge is equal to the offset amplitude of the trailing edge.

[0018] Another embodiment of the present application provides a fan, comprising the impeller described above.

[0019] The embodiment of the present application provides an impeller and a fan, wherein the impeller is provided with wave crests and wave troughs extending from the leading edge of the blade to the trailing edge of the blade, so as to form airflow channels extending from the leading edge to the trailing edge on the pressure side and the suction side of the blade respectively through the wave crests and wave troughs, and at the same time, the waveform of the leading edge is determined by the leading edge offset amplitude and the leading edge angle curve equation of the impeller obtained after the original impeller is modulated by the sine modulation equation, and the waveform of the trailing edge is determined by the trailing edge offset amplitude and the wrap angle curve equation of the impeller obtained after the original impeller is modulated by the sine modulation equation. For the impeller, firstly, since the airflow channel is formed, when the airflow flows through the blade, the airflow on the pressure side and the suction side can flow along the corresponding airflow channel, and the airflow is distributed more evenly on the blade surface, thereby better processing the separation vortex on the blade surface, and further reducing the vortex noise. Secondly, since the airflow channels formed by the crests and troughs are staggered on opposite sides of the blades, the separation of the airflows on the pressure side and the suction side at the trailing edge can be staggered, thereby reducing the vortex noise caused by the separation and concentration of the airflow. Finally, the waveform of the leading edge is determined by the offset amplitude of the leading edge and the leading edge angle curve equation of the impeller obtained after the original impeller is modulated by the sinusoidal modulation equation, and the waveform of the trailing edge is determined by the offset amplitude of the trailing edge and the wrap angle curve equation of the impeller obtained after the original impeller is modulated by the sinusoidal modulation equation. This makes it easier to control the floating changes of the blade surface, making the pressure distribution of the impeller on the blades more uniform, while reducing the pressure loss of the impeller, and also improving the noise. In other words, the impeller of the embodiment of the present application can better improve the noise reduction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the structure of an impeller according to an embodiment of the present application;

[0021] Figure 2 for Figure 1 A schematic diagram of the structure of the impeller from another perspective is shown;

[0022] Figure 3 is the structural diagram of the original impeller;

[0023] Figure 4 for Figure 3 The schematic diagram of the structure of the original impeller shown;

[0024] Figure 5 for Figure 1 The impeller shown is Figure 3 Leading edge angle graph of the original impeller shown;

[0025] Figure 6 for Figure 1 The impeller shown is Figure 3 The wrap angle curve of the original impeller is shown.

[0026] Figure 7 for Figure 1 The impeller shown is Figure 3 Noise comparison graph of the original impeller shown;

[0027] Figure 8 for Figure 1 The impeller shown is Figure 3 Power comparison diagram of the original impeller shown.

[0028] Description of Reference Numerals

[0029] 10. Impeller; 11. Blades; 11a. Crest; 11b. Trough; 11c. Airflow channel; 11d. Leading edge; 11e. Trailing edge; 11f. Blade root; 11g. Blade tip; 12. Hub; 10′, original impeller; 11′, original blades; 11a′, leading edge line; 11b′, trailing edge line; 11c′, blade root line; 11d′, blade tip line; 12′, original hub. DETAILED DESCRIPTION

[0030] The present application embodiment provides a fan, see Figure 1 and Figure 2 , the fan includes an impeller 10.

[0031] The type of fan is not limited, for example, the fan can be an axial flow fan, a centrifugal fan, a mixed flow fan, etc.

[0032] The embodiment of the present application is described by taking the impeller 10 of an axial flow fan as an example.

[0033] See also Figure 1 and Figure 2 The impeller 10 includes a plurality of blades 11, which rotate around a rotation axis Z. The blade 11 has a peak 11a formed by protruding from the suction side of the blade 11 to the pressure side of the blade 11 and a trough 11b formed by being recessed from the pressure side to the suction side. The peak 11a and the trough 11b both extend from the leading edge 11d of the blade 11 to the trailing edge 11e of the blade 11, so that the blade 11 forms an airflow channel 11c extending from the leading edge 11d to the trailing edge 11e on the pressure side and the suction side, respectively. The waveform of the leading edge 11d is determined by the offset amplitude of the leading edge 11d and the leading edge angle curve equation of the impeller 10 obtained after the original impeller 12′ is modulated by the sine modulation equation, and the waveform of the trailing edge 11e is determined by the offset amplitude of the trailing edge 11e and the wrap angle curve equation of the wrap angle of the impeller 10 obtained after the original impeller 12′ is modulated by the sine modulation equation.

[0034] Specifically, Figure 1The impeller 10 shown has a hub 12 , and a plurality of blades 11 are arranged at intervals along the outer circumference of the hub 12 . The rotation centerline of the hub 12 is equivalent to the rotation axis Z of the plurality of blades 11 .

[0035] The blade 11 has two surfaces arranged opposite to each other, one surface is the suction surface, and the other surface is the pressure surface. The suction side refers to the side of the blade 11 provided with the suction surface, and the pressure side refers to the side of the blade 11 provided with the suction surface.

[0036] The leading edge 11d is the outer edge of the blade 11 located on the wind inlet side, and the trailing edge 11e is the outer edge of the blade 11 located on the wind outlet side.

[0037] Since the wave crest 11 a and the wave trough 11 b extend from the leading edge 11 d of the blade 11 to the trailing edge 11 e of the blade 11 , the leading edge 11 d and the trailing edge 11 e both form waveforms corresponding to the wave crest 11 a and the wave trough 11 b .

[0038] For the convenience of description, the waveform described in the present application refers to the waveform formed by the middle surface of the blade 11 .

[0039] In the field of fans, for ease of design, it is usually necessary to simplify the blade 11 into a curved surface without thickness, which is called the middle surface. The middle surface is located between the suction surface and the pressure surface, and the distance between the suction surface and the middle surface is equal to the distance between the pressure surface and the middle surface.

[0040] See also Figure 1 and Figure 2 , the airflow channel 11c is the channel for airflow during the operation of the fan, that is, the airflow flowing through the surface of the blade 11 mainly flows along the airflow channel 11c. Since the peaks 11a and the troughs 11b are formed on the blade 11, the pressure side and the suction side of the blade 11 are also formed with airflow channels 11c, respectively, wherein the airflow channel 11c on the pressure side is formed by the troughs 11b, and the airflow channel 11c on the suction side is formed by the peaks 11a, that is, the troughs 11b are the concave spaces formed on the pressure side, and the concave spaces on the pressure side are the airflow channel 11c on the pressure side, while the protruding peaks 11a are the concave spaces formed on the suction side, and the concave spaces on the suction side are the airflow channel 11c on the suction side. It should be noted that the airflow channel 11c described in the present application only refers to the above-mentioned areas corresponding to the trough 11b and the peak 11a, and does not refer to all areas formed by the intervals between two adjacent peaks 11a (the space formed by the depression of the trough 11b between two adjacent peaks 11a is the airflow channel 11c), nor does it refer to all areas formed by the intervals between two adjacent troughs 11b (the space formed by the depression of the peak 11a on the suction side between two adjacent troughs 11b is the airflow channel 11c).

[0041] Please continue reading Figure 1 The airflow channel 11c on the pressure side and the airflow channel 11c on the suction side are staggered on opposite sides of the blade 11 (that is, the airflow channel 11c on the pressure side and the airflow channel 11c on the suction side are not aligned along the thickness direction of the blade 11). Therefore, the position where the airflow on the pressure side flows into the airflow channel 11c is staggered with the position where the airflow on the suction side flows into the airflow channel 11c, and the position where the airflow on the pressure side flows out of the airflow channel 11c is also staggered with the position where the airflow on the suction side flows out of the airflow channel 11c.

[0042] See also Figure 3 and Figure 4 , the original impeller 10′ is not Figure 1 and Figure 2 The impeller 10 shown has crests 11a and troughs 11b. The original impeller 10′ can be considered as the prototype of the impeller 10, that is, the original impeller 10′ does not have crests 11a and troughs 11b. The original impeller 10′ can be used to determine the waveform of the leading edge 11d and the waveform of the trailing edge 11e of the impeller 10 described in the present application.

[0043] See also Figure 1 and Figure 2 , the outer edge of the blade 11 on the side close to the rotation axis is the blade root 11f, the outer edge of the blade 11 on the side away from the rotation axis is the blade tip 11g, the leading edge 11d and the trailing edge 11e extend from the blade root 11f to the blade tip 11g respectively. The convex part corresponding to the wave crest 11a on the waveform of the leading edge 11d has the highest point, and the concave part corresponding to the wave trough 11b has the lowest point, the highest point can be called the leading edge wave crest point Qf, and the lowest point can be called the leading edge wave trough point Qg. Similarly, the convex part corresponding to the wave crest 11a on the waveform of the trailing edge 11e has the highest point, and the concave part corresponding to the wave trough 11b has the lowest point, the highest point can be called the trailing edge wave crest point Wf, and the lowest point can be called the trailing edge wave trough point Wg.

[0044] The offset amplitude of the leading edge 11d refers to the offset amplitude of the leading edge peak point Qf and the offset amplitude of the leading edge trough point Qg, wherein the offset amplitude of the leading edge peak point Qf refers to the height amplitude between the leading edge peak point Qf and the initial middle surface, and the offset amplitude of the leading edge trough point Qg refers to the height amplitude between the leading edge trough point Qg and the initial middle surface.

[0045] The offset amplitude of the trailing edge 11e refers to the offset amplitude of the trailing edge peak point Wf and the offset amplitude of the trailing edge trough point Wg, wherein the offset amplitude of the trailing edge peak point Wf refers to the height amplitude between the trailing edge peak point Wf and the initial middle surface, and the offset amplitude of the trailing edge trough point Wg refers to the height amplitude between the trailing edge trough point Wg and the initial middle surface.

[0046] Assuming that the middle surface forms the waveform of the leading edge 11d and the waveform of the trailing edge 11e after bending, then the middle surface before bending is the initial middle surface mentioned above, and the middle surface of the original impeller 10' can also be regarded as the initial middle surface.

[0047] The offset amplitude of the leading edge 11d can be used to determine the depth of the airflow channel 11c at the leading edge 11d, wherein the offset amplitude of the leading edge crest point Qf is equivalent to the depth of the airflow channel 11c located on the suction side at the leading edge 11d, and the offset amplitude of the leading edge trough point Qg is equivalent to the depth of the airflow channel 11c located on the pressure side at the leading edge 11d.

[0048] The offset amplitude of the trailing edge 11e can be used to determine the depth of the airflow channel 11c at the trailing edge 11e, wherein the offset amplitude of the trailing edge peak point Wf is equivalent to the depth of the airflow channel 11c located on the suction side at the trailing edge 11e, and the offset amplitude of the trailing edge trough point Wg is equivalent to the depth of the airflow channel 11c located on the pressure side at the trailing edge 11e.

[0049] The values ​​of the offset amplitude of the leading edge 11d and the offset amplitude of the trailing edge 11e can be determined according to design requirements.

[0050] For the sake of distinction, the offset amplitude of the leading edge crest point Qf can be represented by a positive number, and the offset amplitude of the leading edge trough point Qg can be represented by a negative number. The offset amplitude of the leading edge crest point Qf can be equal to the absolute value of the offset amplitude of the leading edge trough point Qg. For example, the offset amplitude of the leading edge crest point Qf can be 1, and the offset amplitude of the leading edge trough point Qg can be -1, where 1=|-1|. The offset amplitude of the leading edge crest point Qf can also be different from the absolute value of the offset amplitude of the leading edge trough point Qg. For example, the offset amplitude of the leading edge crest point Qf can be 1, and the offset amplitude of the leading edge trough point Qg can be -0.5, where 1≠|-0.5|.

[0051] Similarly, the offset amplitude of the trailing edge crest point Wf can be represented by a positive number, and the offset amplitude of the trailing edge trough point Wg can be represented by a negative number. The offset amplitude of the trailing edge crest point Wf can be equal to the absolute value of the offset amplitude of the trailing edge trough point Wg. For example, the offset amplitude of the trailing edge crest point Wf can be 1, and the offset amplitude of the trailing edge trough point Wg can be -1, where 1=|-1|. The offset amplitude of the trailing edge crest point Wf can also be different from the absolute value of the offset amplitude of the trailing edge trough point Wg. For example, the offset amplitude of the trailing edge crest point Wf can be 1, and the offset amplitude of the trailing edge trough point Wg can be -0.5, where 1≠|-0.5|.

[0052] Preferably, the offset amplitude of the leading edge 11d can be equal to the offset amplitude of the trailing edge 11e, which is equivalent to that from the leading edge 11d to the trailing edge 11e, the crest 11a is of equal height and the trough 11b is also of equal height. This arrangement is convenient for the processing and manufacturing of the blade 11, especially for the mold opening.

[0053] More preferably, under the premise that the offset amplitude of the leading edge 11d is equal to the offset amplitude of the trailing edge 11e, the offset amplitude of the leading edge peak point Qf can be equal to the absolute value of the offset amplitude of the leading edge trough point Qg, and the offset amplitude of the trailing edge peak point Wf can be equal to the absolute value of the offset amplitude of the trailing edge trough point Wg, which is equivalent to the height of the peak 11a being the same as the height of the trough 11b.

[0054] The offset amplitude of the leading edge 11d and the offset amplitude of the trailing edge 11e are only part of the parameters of the waveform of the leading edge 11d and the waveform of the trailing edge 11e. The other parameters of the waveform of the leading edge 11d can be determined by the leading edge angle curve equation of the impeller 10 obtained by modulating the original impeller 10′ with the sinusoidal modulation equation. The other parameters of the waveform of the trailing edge 11e can be determined by the wrap angle curve equation of the impeller 10 obtained by modulating the original impeller 10′ with the sinusoidal modulation equation.

[0055] For example, the sinusoidal modulation equation may be obtained by modulating the leading edge angle curve equation of the original impeller 10 ′ to obtain the leading edge angle curve equation of the impeller 10 .

[0056] On the projection plane perpendicular to the rotation axis of the impeller 10, the projection of the rotation axis of the impeller 10 is used as the origin of the coordinate system, and the X-axis, the Y-axis and a plurality of tangent circles with the origin of the coordinate system as the center are defined. The angle between the line between any point on the projection of the leading edge 11d and the origin of the coordinate system and the X-axis is the leading edge angle of the impeller 10. In the following content, the leading edge angle will be further explained by taking the original impeller 10′ as an example.

[0057] The leading edge angle curve equation of the original impeller 10' is a curve equation determined by the leading edge angle φ1 of the original impeller 10'.

[0058] by Figure 3 As an example, see the original impeller 10′ shown in FIG. Figure 4 , on the projection plane perpendicular to the rotation axis of the original impeller 10′ ( Figure 4The projection of the leading edge of the original blade 11′ of the original impeller 10′ forms a leading edge line 11a′, the projection of the trailing edge of the original blade 11′ forms a trailing edge line 11b′, the projection of the root of the original blade 11′ forms a root line 11c′, and the projection of the tip of the original blade 11′ forms a tip line 11d′. The projection of the rotation axis is taken as the center O, the distance between the point on the root line 11c′ farthest from the center O and the center O is taken as the minimum radius R1 (if the distance between any point on the root line 11c′ and the center O is equal, then the distance is regarded as the minimum radius R1), and the minimum distance between the point on the tip line 11d′ closest to the center O and the center O is taken as the maximum radius R2 (if the distance between any point on the root line 11c′ and the center O is equal, then the distance is regarded as the maximum radius R2). An annular area (i.e. Figure 4 In the annular area, a plurality of concentric and equidistantly distributed cutting circles Fq can be defined. That is to say, all the cutting circles Fq are centered on the center O, and the distances between every two adjacent cutting circles Fq are equal.

[0059] It should be noted that, of the two circles constituting the outer contour of the annular region, the circle closest to the center O (i.e., the circle with the smallest radius R1) is Figure 4 In the figure, the outer contour of the original hub 12′12 coincides with the circle) is the first cutting circle Fq, and the circle farthest from the center O (that is, the circle with a radius of the maximum radius R2) can be the cutting circle Fq or not. For example, if the distance between the circle and the adjacent cutting circle Fq is equal to the distance between any other two adjacent cutting circles Fq, then the circle can be regarded as one of the cutting circles Fq, otherwise, the circle is not regarded as the cutting circle Fq.

[0060] Please continue reading Figure 4 , with the center O as the origin of the coordinate system, the center line along the horizontal coordinate change as the X-axis, the center line along the vertical coordinate change as the Y-axis, the intersection of each cutting circle Fq and the leading edge line 11a′ is the leading edge point N1, and the angle between the line between the leading edge point N1 and the origin of the coordinate system and the X-axis is the leading edge angle φ1 of the original impeller 10′.

[0061] It should be noted that the leading edge angle of the impeller 10 is defined in the same manner as the leading edge angle φ1 of the original impeller 10 ′.

[0062] The leading edge angle curve equation of the original impeller 10′ is a known curve equation. After the leading edge angle curve equation of the original impeller 10′ is modulated by the sinusoidal modulation equation, the resulting leading edge angle curve equation of the impeller 10 is the curve equation of the leading edge angle of the impeller 10. The leading edge line 11a′ of the impeller 10 can be fitted based on the leading edge line 11a′ of the impeller 10, and the waveform of the leading edge 11d can be obtained based on the leading edge line 11a′ of the impeller 10 and the determined offset amplitude of the leading edge 11d.

[0063] Exemplarily, the sinusoidal modulation equation is obtained by modulating the wrap angle curve equation of the original impeller 10 ′ to obtain the wrap angle curve equation of the wrap angle of the impeller 10 .

[0064] On the projection plane perpendicular to the rotation axis of the impeller 10, the angle between the intersection of the projection of the leading edge 11d and the projection of the trailing edge 11e with the same tangent circle and the line connecting the origin of the coordinate system is the wrap angle of the impeller 10. In the following content, the wrap angle will still be further explained by taking the original impeller 10' as an example.

[0065] The wrap angle curve equation of the original impeller 10' is a curve equation determined by the wrap angle θ1 of the original impeller 10'.

[0066] Still Figure 4 Taking the original impeller 10′ shown as an example, the intersection of each cutting circle Fq and the trailing edge line 11b′ is the trailing edge point N2, and the angle between the line connecting the leading edge point N1 and the trailing edge point N2 located on the same cutting circle Fq and the origin of the coordinate system is the wrap angle θ1 of the original impeller 10′.

[0067] It should be noted that the wrap angle of the impeller 10 is defined in the same manner as the wrap angle φ1 of the original impeller 10 ′.

[0068] The wrap angle curve equation of the original impeller 10′ is a known curve equation. After the wrap angle curve equation of the original impeller 10′ is modulated by the sinusoidal modulation equation, the obtained wrap angle curve equation of the impeller 10 is the curve equation of the wrap angle of the impeller 10. According to the wrap angle curve equation of the impeller 10, the trailing edge line 11b′ of the impeller 10 can be fitted. According to the trailing edge line 11b′ of the impeller 10 and the determined offset amplitude of the trailing edge 11e, the waveform of the trailing edge 11e can be obtained.

[0069] In the related art, for an impeller whose leading and trailing edges of the blades are set to be serrated, during the operation of the fan, the serrations of the leading and trailing edges can break up the separated large vortices, but the separated vortices on the blade surface cannot be processed.

[0070] The impeller 10 of the embodiment of the present application is provided with a crest 11a and a trough 11b on the blade 11 extending from the leading edge 11d of the blade 11 to the trailing edge 11e of the blade 11, so as to form an airflow channel 11c extending from the leading edge 11d to the trailing edge 11e on the pressure side and the suction side of the blade 11 through the crest 11a and the trough 11b, respectively. At the same time, the waveform of the leading edge 11d is determined by the offset amplitude of the leading edge 11d and the leading edge angle curve equation of the impeller 10 obtained by modulating the original impeller 12′ with the sinusoidal modulation equation, and the waveform of the trailing edge 11e is determined by the offset amplitude of the trailing edge 11e and the wrap angle curve equation of the wrap angle of the impeller 10 obtained by modulating the original impeller 12′ with the sinusoidal modulation equation. For the impeller 10, firstly, since the airflow channel 11c is formed, when the airflow flows through the blade 11, the airflow on the pressure side and the suction side can flow along the corresponding airflow channel 11c, and the airflow is distributed more evenly on the blade surface, thereby better processing the separation vortex on the blade surface, and further reducing the vortex noise. Secondly, since the airflow channel 11c formed by the wave crest 11a and the wave trough 11b is staggered on the opposite sides of the blade 11, the separation of the airflow on the pressure side and the suction side at the trailing edge 11e can be staggered, thereby also reducing the vortex noise caused by the concentrated separation of the airflow. Finally, the waveform of the leading edge 11d is determined by the offset amplitude of the leading edge 11d and the leading edge angle curve equation of the impeller 10 obtained after the original impeller 12′ is modulated by the sine modulation equation, and the waveform of the trailing edge 11e is determined by the offset amplitude of the trailing edge 11e and the wrap angle curve equation of the impeller 10 obtained after the original impeller 12′ is modulated by the sine modulation equation, so that the peak 11a and the trough 11b can be extended from the leading edge 11d to the trailing edge 11e more smoothly, and accordingly, the direction of the airflow channel 11c is also smoother, thereby facilitating the control of the floating change of the blade surface, making the pressure distribution of the impeller 10 on the blade 11 more uniform, and reducing the pressure loss of the impeller 10 while also improving the noise. In other words, the impeller 10 of the embodiment of the present application can better improve the noise reduction effect.

[0071] In addition, for axial flow fans, according to the speed distribution of the impeller, the negative pressure is the largest at the position close to the blade tip. Therefore, during the operation of the axial flow fan, the airflow tends to flow radially from the blade root to the blade tip. The axial flow fan in the related art cannot control the airflow to converge to the blade tip, which will cause uneven distribution of airflow on the blade surface and high noise.

[0072] When the impeller 10 of the present application is applied to an axial flow fan, since the airflows on the pressure side and the suction side can flow along the corresponding airflow channels 11c, it can better handle the separation vortex on the blade surface while also suppressing the airflow from gathering toward the blade top 11g. Therefore, for the axial flow fan, the impeller 10 of the present application has a better noise reduction effect.

[0073] In one embodiment, please refer to Figure 1 and 2 , a phase difference may be formed between the waveform of the leading edge 11d and the waveform of the trailing edge 11e.

[0074] The phase difference between the waveform of the leading edge 11 d and the waveform of the trailing edge 11 e means that in the same coordinate system, the waveform of the leading edge 11 d and the waveform of the trailing edge 11 e have a phase difference.

[0075] See also Figure 2 , on the projection plane perpendicular to the rotation axis Z of the impeller 10 ( Figure 2 Equivalent to the projection of the impeller 10 on the projection plane), multiple reference circles Ck can be defined with the projection of the rotation axis Z as the center. For the axial flow fan, there is a phase difference between the waveform of the leading edge 11d and the waveform of the trailing edge 11e, which means that the leading edge peak point Qf and the trailing edge peak point Wf are not on the same reference circle Ck, and the leading edge trough point Qg and the trailing edge trough point Wg are also not on the same reference circle Ck.

[0076] It should be noted that the reference circle Ck is not completely the same as the aforementioned slicing circle Fq, and the multiple reference circles Ck may be equidistantly distributed or may not be equidistantly distributed, that is, the slicing circle Fq can be considered as an equidistantly distributed reference circle Ck.

[0077] It should be noted that, for a centrifugal fan, the blades on its impeller have a leading edge close to the axis of rotation and a trailing edge away from the axis of rotation. Therefore, for a centrifugal fan, a phase difference is formed between the waveform of the leading edge and the waveform of the trailing edge. This can be understood as a phase difference formed between the projection of the waveform of the leading edge and the projection of the waveform of the trailing edge on a projection plane parallel to the waveform of the leading edge.

[0078] A phase difference is formed between the waveform of the leading edge 11d and the waveform of the trailing edge 11e, so that the crest 11a and the trough 11b can extend more smoothly from the leading edge 11d to the trailing edge 11e, and the direction of the airflow channel 11c is also smoother. When the airflow flows along the airflow channel 11c, the pressure loss of the impeller 10 is further reduced, thereby also better reducing noise.

[0079] In one embodiment, please refer to Figure 1 and 2For the impeller 10 in which the outer edge of the blade 11 on the side close to the rotation axis Z is the blade root 11f, and the outer edge on the side away from the rotation axis Z is the blade tip 11g, from the leading edge 11d to the trailing edge 11e, the wave crest 11a and the wave trough 11b can be gradually deflected toward the direction close to the rotation axis Z. In other words, from the leading edge 11d to the trailing edge 11e, the airflow channel 11c is gradually deflected toward the direction close to the rotation axis Z, and the airflow flows into the airflow channel 11c from a position relatively far from the rotation axis Z, and then flows out of the airflow channel 11c from a position relatively close to the rotation axis Z, which is equivalent to the airflow flowing on the blade surface of the blade 11 being deflected in the direction close to the rotation axis Z under the guidance of the airflow channel 11c, thereby reducing the resistance of the airflow flow and making the airflow flow more smoothly on the blade surface.

[0080] In one embodiment, the sinusoidal modulation equation is represented by f(Q), and the leading edge angle curve equation Y of the impeller 10 is φ2 Can be: Y φ2 =y φ1 +f(X), the wrap angle curve equation Y of the impeller 10 θ2 Can be: Y θ2 =y θ1 +f(X+k). φ1 The leading edge angle curve equation of the original blade 11′, y θ1 represents the wrap angle curve equation of the original blade 11′, X represents the Xth cutting circle Fq of the original blade 11′, 1≤X≤X max , X max Indicates the maximum number of set cutting circles Fq, X max ≥3, k represents the number of phases, and k is not equal to 0.

[0081] by Figure 4 Taking the original impeller 10′ shown as an example, the cutting circle Fq closest to the center of the circle is taken as the first cutting circle Fq, and the cutting circle Fq farthest from the center of the circle is taken as the last cutting circle Fq. X=1 represents the first cutting circle Fq, X=2 represents the second cutting circle Fq, and so on.

[0082] X max is the maximum number of cutting circles Fq divided in the annular area, X max The specific value of X can be determined according to design requirements. max At least 3, for example, X max =3, which means that the annular area can be divided into three cutting circles Fq, X max =10, which is equivalent to 10 cutting circles Fq being able to be divided in the annular area.

[0083] Preferably, X max Can be greater than or equal to 15 and less than or equal to 45, that is: 15≤Xmax ≤45.

[0084] Q in f(Q) is the independent variable. The leading edge angle curve equation Y of the impeller 10 is φ2 In the equation, Q = X, the wrap angle curve equation Y of the impeller 10 is θ2 In the figure, Q=X+k, where k is actually the phase difference between the waveform of the leading edge 11d and the waveform of the trailing edge 11e, that is, the phase difference between the waveform of the leading edge 11d and the waveform of the trailing edge 11e is k.

[0085] The value of k can be determined according to design requirements. For example, k=1, that is, Y θ2 =y θ1 +f(X+1), which is equivalent to a phase shift between the waveform of the leading edge 11d and the waveform of the trailing edge 11e.

[0086] For example, the leading edge angle curve equation y of the original impeller 10 ′ is φ1 Can be:

[0087] y φ1 =-47.346x+11.705, where x represents the dimensionless value of the cutting circle Fq, x=X / X max .

[0088] For example, the wrap angle curve equation y of the original impeller 10 ′ is θ1 Can be:

[0089] y θ1 =24.802x 3 -14.089x 2 -3.9464x+81.4.

[0090] In addition, the cutting circle Fq can also be used to determine the width of each airflow channel 11c. The width mentioned here refers to the maximum value of the width of the airflow channel 11c in the cross section.

[0091] For example, on the projection surface where the cutting circle Fq is located, the projection of the wave crest 11a and the projection of the adjacent wave trough 11b constitute a band of the waveform projection, and there may be at least two cutting circles Fq in each 1 / 2 band.

[0092] A half wave band corresponds to one airflow channel 11c, and one wave band corresponds to two airflow channels 11c, one of which is formed by the wave crest 11a on the suction side, and the other is formed by the wave trough 11b on the pressure side. That is to say, at least two cutting circles Fq pass through the projection area of ​​each airflow channel 11c.

[0093] by Figure 4Taking the original impeller 10′ shown as an example, Figure 4 The projection plane where the cutting circle Fq in the figure is located is the projection plane perpendicular to the rotation axis of the original impeller 10′. max =15, if there are two cutting circles Fq in each 1 / 2 band, the number of 1 / 2 bands is 7 (i.e., 15=2×7+1), which is equivalent to the total number of airflow channels 11c on the suction side and the pressure side of the blade 11 of the impeller 10 after modulation being 7. In addition, there is one extra cutting circle Fq that can define 0.5 airflow channels 11c, which is equivalent to an incomplete airflow channel 11c at the location of the extra cutting circle Fq.

[0094] Exemplarily, the sinusoidal modulation equation f(Q) may be: f(Q)=A×sin(0.5×Q×π), where A represents the amplitude of the sinusoidal modulation equation.

[0095] Preferably, -2≤A≤2, and A is not equal to 0. Within this value range, the wave crest 11a and the wave trough 11b can transition smoothly, and the mold opening is relatively simple.

[0096] More preferably, A=1.

[0097] In addition, A can also be used to set the offset amplitude of the leading edge 11d. For example, if A is a positive number, the offset amplitude of the crest point 11a of the leading edge 11d is A, and the offset amplitude of the trough point 11b of the leading edge 11d is -A. If A is a negative number, the offset amplitude of the crest point 11a of the leading edge 11d is -A, and the offset amplitude of the trough point 11b of the leading edge 11d is A. The absolute value of A |A| is the depth of the airflow channel 11c at the leading edge 11d.

[0098] Similarly, A can also be used to set the offset amplitude of the trailing edge 11e. For example, if A is a positive number, the offset amplitude of the crest point 11a of the trailing edge 11e is A, and the offset amplitude of the trough point 11b of the trailing edge 11e is -A. If A is a negative number, the offset amplitude of the crest point 11a of the trailing edge 11e is -A, and the offset amplitude of the trough point 11b of the trailing edge 11e is A. The absolute value of A |A| is the depth of the airflow channel 11c at the trailing edge 11e.

[0099] See also Figure 5 , Figure 5 The leading edge angle curve equation y of the original impeller 10′ is shown. φ1 The curve and the leading edge angle curve equation Y of the impeller 10 φ2 The curve, where y φ1 =-47.346x+11.705, the sinusoidal modulation equation f(Q) is: f(Q)=A×sin(0.5×Q×π), Y φ2 =y φ1 +f(X).

[0100] See also Figure 6 , Figure 6 The following is the curve equation y of the original impeller 10′: θ1 The curve and the wrap angle curve equation Y of the impeller 10 θ2 The curve, where y θ1 =24.802x 3 -14.089x 2 -3.9464x+81.4, the sinusoidal modulation equation f(Q) is: f(Q)=A×sin(0.5×Q×π), Y θ2 =y θ1 +f(X+1).

[0101] See also Figure 7 Compared with the original impeller 10', under the same air volume, the noise of the impeller 10 of the present application can be reduced by at least 0.9dB(A), and the noise reduction effect is significantly improved.

[0102] See also Figure 8 Compared with the original impeller 10', under the same air volume, the power of the impeller 10 of the present application can be reduced by at least 8%, and the efficiency of the fan is also greatly improved.

[0103] In the description of the present application, the description with reference to the terms "in one embodiment", "in some embodiments", "in other embodiments", "in yet other embodiments", or "exemplary" etc. means that the specific features, regions, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In the present application, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, regions, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine different embodiments or examples described in the present application and the features of different embodiments or examples without contradiction.

[0104] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims

1. An impeller, characterized in that: include: A plurality of blades rotating around a rotation axis, wherein the blades have a wave crest protruding from the suction side of the blade to the pressure side of the blade and a wave trough recessed from the pressure side to the suction side, wherein both the wave crest and the wave trough extend from the leading edge of the blade to the trailing edge of the blade, so that the blade forms an airflow channel extending from the leading edge to the trailing edge on the pressure side and the suction side, respectively; wherein the waveform of the leading edge is determined by the leading edge angle curve equation of the leading edge angle of the impeller obtained by modulating the original impeller with a sine modulation equation, and the waveform of the trailing edge is determined by the trailing edge angle curve equation of the wrap angle of the impeller obtained by modulating the original impeller with a sine modulation equation; Among them, on the projection plane perpendicular to the rotation axis, with the projection of the rotation axis as the origin of the coordinate system, an X-axis, a Y-axis and a plurality of tangent circles with the origin of the coordinate system as the center are defined, the angle between the line between any point on the projection of the leading edge and the origin of the coordinate system and the X-axis is the leading edge angle, and the angle between the line between the intersection points of the projection of the leading edge and the projection of the trailing edge with the same tangent circle and the origin of the coordinate system is the wrap angle.

2. The impeller according to claim 1, characterized in that: A phase difference is formed between the waveform of the leading edge and the waveform of the trailing edge.

3. The impeller according to claim 1 or 2, characterized in that: The outer edge of the blade close to the rotation axis is the blade root, and the outer edge away from the rotation axis is the blade tip. From the leading edge to the trailing edge, the wave crest and the wave trough gradually deflect toward the direction close to the rotation axis.

4. The impeller according to claim 1 or 2, characterized in that: The sinusoidal modulation equation is represented by f(Q), and the leading edge angle curve equation of the impeller is Y φ2 For: Y φ2 =y φ1 +f(X), the impeller wrap angle curve equation Y θ2 For: Y θ2 =y θ1 +f(X+k); Among them, y φ1 The leading edge angle curve equation of the original impeller is represented by y θ1 represents the wrap angle curve equation of the original impeller, X represents the Xth cutting circle of the original impeller, 1≤X≤X max , X max Indicates the maximum number of cutting circles set, X max ≥3, k represents the number of phases, and k is not equal to 0.

5. The impeller according to claim 4, characterized in that: 15≤X max ≤45; and / or, k=1.

6. The impeller according to claim 4, characterized in that The width of each of the air flow channels is determined by the number of the cutting circles.

7. The impeller according to claim 6, characterized in that On the projection surface where the cutting circle is located, the projection of the wave crest and the projection of the adjacent wave trough constitute a band of the waveform projection, and there are at least two cutting circles in each 1 / 2 band.

8. The impeller according to claim 1, characterized in that The sinusoidal modulation equation f(Q) is: f(Q)=A×sin(0.5×Q×π), where A represents the amplitude of the sinusoidal modulation equation.

9. The impeller according to claim 8, characterized in that -2≤A≤2, and A is not equal to 0.

10. The impeller according to claim 1, characterized in that The offset amplitude of the leading edge is equal to the offset amplitude of the trailing edge.

11. A fan, characterized in that: The impeller comprises the impeller described in any one of claims 1 to 10.

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