Impeller and fan

Abstract

The embodiment of the present application provides a kind of impeller and fan, wherein the impeller includes: a plurality of blades rotating around a rotation axis, the blade has the wave crest formed from the suction side of blade to the pressure side of blade and the wave trough formed from the pressure side to the suction side, the wave crest and the wave trough are extended from the leading edge of blade to the trailing edge of blade, so that the blade forms airflow channel from the leading edge to the trailing edge on the pressure side and the suction side respectively;Wherein, wherein, the waveform of leading edge is determined by the offset amplitude of leading edge and the leading edge angle curve equation of the leading edge angle of the impeller obtained by modulating original impeller by sine modulation equation, the waveform of trailing edge is determined by the offset amplitude of trailing edge and the wrap angle curve equation of the wrap angle of the impeller obtained by modulating original impeller by sine modulation equation.The impeller of the embodiment of the present application can improve the noise reduction effect.

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 home appliances. For example, axial fans are commonly used in appliances like air conditioner outdoor units and fans, while centrifugal fans are used in appliances like fresh air blowers. Home appliances generally have high noise requirements, so reducing the low- and medium-frequency noise of fans has long been a research focus.

[0003] To reduce low- and medium-frequency noise, one type of fan has a serrated blade on its impeller. This serrations break up and separate large vortices. While this impeller has some effect in reducing noise, the improvement 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 objectives, an embodiment of the present application provides an impeller, comprising:

[0006] A plurality of blades rotating about a rotation axis, the blades having a crest protruding from the suction side of the blade toward the pressure side of the blade and a trough recessed from the pressure side toward the suction side, the crest and the trough both extending 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 offset amplitude of the leading edge and the leading edge angle curve equation 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 offset amplitude and the wrap angle curve equation of the impeller obtained by modulating the original impeller with the 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, the X-axis, Y-axis and multiple 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 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 are gradually deflected 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's wrap angle curve equation Y θ2 For: Y θ2 =y θ1 +f(X+k);

[0011] Among them, y φ1 The equation for the leading edge angle curve of the original impeller, 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 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 0.

[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, including the impeller described above.

[0019] An 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 an airflow channel 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's leading edge angle 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's wrap angle obtained after the original impeller is modulated by the sine modulation equation. For this 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 more evenly distributed on the blade surface, thereby better handling the separation vortex on the blade surface, and thus reducing the vortex noise. Secondly, since the airflow channels formed by the crests and troughs are staggered on opposite sides of the blade, the separation of the airflow 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 blade 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 This is a schematic structural diagram of an impeller according to an embodiment of the present application;

[0021] Figure 2 for Figure 1 The structural diagram 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 is 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 and the original impeller shown in Figure 3 the noise comparison chart of the impeller and the original impeller shown in

[0027] Figure 8 For Figure 1 the impeller and the original impeller shown in Figure 3 the power comparison chart of the impeller and the original impeller shown in

[0028] BRIEF DESCRIPTION OF DRAWINGS

[0029] 10, impeller; 11, blade; 11a, wave crest; 11b, wave trough; 11c, air flow passage; 11d, leading edge; 11e, trailing edge; 11f, blade root; 11g, blade tip; 12, hub; 10', original impeller; 11', original blade; 11a', leading edge line; 11b', trailing edge line; 11c', blade root line; 11d', blade tip line; 12', original hub. DETAILED DESCRIPTION

[0030] Embodiments of the present application provide a fan, please refer to 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 fan, centrifugal fan, mixed flow fan, etc.

[0032] Embodiments of the present application take the impeller 10 of the axial fan as an example for description.

[0033] Please refer to Figure 1 and Figure 2 , the impeller 10 includes a plurality of blades 11, the plurality of blades 11 rotates around a rotation axis Z. The blade 11 has a wave crest 11a formed from the suction side of the blade 11 to the pressure side of the blade 11 and a wave trough 11b formed from the pressure side to the suction side, the wave crest 11a and the wave trough 11b are extended 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 air flow passage 11c from the leading edge 11d to the trailing edge 11e on the pressure side and the suction side respectively. Wherein, the wave shape 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 leading edge angle of the impeller 10 obtained by modulating the original impeller 12' through the sine modulation equation, the wave shape 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' through 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 11 d is the outer edge of the blade 11 on the wind inlet side, and the trailing edge 11 e is the outer edge of the blade 11 on the wind outlet side.

[0037] Since the crest 11 a and the trough 11 b both extend from the leading edge 11 d 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 crest 11 a and the trough 11 b .

[0038] For the convenience of description, the waveform described in this 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. This curved surface is called the middle surface. The middle surface is located between the suction surface and the pressure surface. 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 through which the airflow circulates 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 wave crests 11a and wave 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. The airflow channel 11c on the pressure side is formed by the wave troughs 11b, and the airflow channel 11c on the suction side is formed by the wave crests 11a. That is, the wave 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 convex wave crests 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 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 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, and 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, and 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 this application.

[0043] See also Figure 1 and Figure 2 The outer edge of blade 11 on the side closest to the rotation axis is blade root 11f, and the outer edge of blade 11 on the side facing away from the rotation axis is blade tip 11g. Leading edge 11d and trailing edge 11e extend from blade root 11f to blade tip 11g, respectively. The convex portion of the waveform of leading edge 11d corresponding to wave crest 11a has a highest point, while the concave portion corresponding to wave trough 11b has a lowest point. This highest point can be referred to as leading edge wave crest point Qf, and the lowest point can be referred to as leading edge wave trough point Qg. Similarly, the convex portion of the waveform of trailing edge 11e corresponding to wave crest 11a has a highest point, while the concave portion corresponding to wave trough 11b has a lowest point. This highest point can be referred to as trailing edge wave crest point Wf, and the lowest point can be referred to as 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 intermediate 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 intermediate surface.

[0046] The intermediate surface before bending can be regarded as the initial intermediate surface, and the intermediate surface of the original impeller 10' can also be regarded as the initial intermediate surface.

[0047] The offset amplitude of the leading edge 11d can be used to determine the depth of the flow passage 11c at the leading edge 11d, wherein the offset amplitude of the leading edge peak point Qf is equal to the depth of the flow passage 11c at the leading edge 11d on the suction side, and the offset amplitude of the leading edge valley point Qg is equal to the depth of the flow passage 11c at the leading edge 11d on the pressure side.

[0048] The offset amplitude of the trailing edge 11e can be used to determine the depth of the flow passage 11c at the trailing edge 11e, wherein the offset amplitude of the trailing edge peak point Wf is equal to the depth of the flow passage 11c at the trailing edge 11e on the suction side, and the offset amplitude of the trailing edge valley point Wg is equal to the depth of the flow passage 11c at the trailing edge 11e on the pressure side.

[0049] 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 convenience of distinction, the offset amplitude of the leading edge peak point Qf can be represented by a positive number, and the offset amplitude of the leading edge valley point Qg can be represented by a negative number. 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 valley point Qg, for example, the offset amplitude of the leading edge peak point Qf can be 1, and the offset amplitude of the leading edge valley point Qg can be -1, 1 = |-1|. The offset amplitude of the leading edge peak point Qf can also not be equal to the absolute value of the offset amplitude of the leading edge valley point Qg, for example, the offset amplitude of the leading edge peak point Qf can be 1, and the offset amplitude of the leading edge valley point Qg can be -0.5, 1 ≠ |-0.5|.

[0051] Similarly, the offset amplitude of the trailing edge peak point Wf can be represented by a positive number, and the offset amplitude of the trailing edge valley point Wg can be represented by a negative number. 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 valley point Wg, for example, the offset amplitude of the trailing edge peak point Wf can be 1, and the offset amplitude of the trailing edge valley point Wg can be -1, 1 = |-1|. The offset amplitude of the trailing edge peak point Wf can also not be equal to the absolute value of the offset amplitude of the trailing edge valley point Wg, for example, the offset amplitude of the trailing edge peak point Wf can be 1, and the offset amplitude of the trailing edge valley point Wg can be -0.5, 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 the wave crests 11a and troughs 11b being of equal height from the leading edge 11d to the trailing edge 11e. This arrangement facilitates the processing and manufacturing of the blade 11, and in particular, facilitates mold making.

[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 crest 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 can 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 a projection plane perpendicular to the rotation axis of impeller 10, with the projection of the rotation axis of impeller 10 as the origin of the coordinate system, the X-axis, Y-axis, and multiple tangent circles centered at the origin of the coordinate system are defined. The angle between the line connecting any point on the projection of leading edge 11d and the origin of the coordinate system and the X-axis is the leading edge angle of impeller 10. The following description will further explain the leading edge angle using 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 FIG4. 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' on the projection plane, 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'. With the projection of the rotation axis as the center O, the distance between the point on the root line 11c' farthest from the center O and the center O as the minimum radius R1 (if the distance between any point on the root line 11c' and the center O is equal, the distance is taken 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 as the maximum radius R2 (if the distance between any point on the root line 11c' and the center O is equal, the distance is taken as the maximum radius R2), a ring-shaped area (i.e. the area surrounded by the circle with the radius R1 and the circle with the radius R2) can be defined, and a plurality of concentric and equidistantly distributed tangent circles Fq can be defined in the ring-shaped area, that is, all the tangent circles Fq have the center O as the center, and the distance between each adjacent two tangent circles Fq is equal. Figure 4

[0059] It should be noted that of the two circles constituting the outer contour of the ring-shaped area, the circle closest to the center O (i.e. the circle with the minimum radius R1, in which the outer contour of the original hub 12'12 coincides with the circle) is the first tangent circle Fq, and the circle farthest from the center O (i.e. the circle with the maximum radius R2) can or can not be a tangent circle Fq, for example, if the distance between the circle and the adjacent tangent circle Fq is equal to the distance between any other two adjacent tangent circles Fq, the circle can be regarded as one of the tangent circles Fq, otherwise, the circle is not regarded as a tangent circle Fq. Figure 4

[0060] Please continue to refer to Figure 4 With the center O as the origin of the coordinate system, the center line changing along the horizontal coordinate as the X axis, and the center line changing along the vertical coordinate as the Y axis, the intersection of each tangent circle Fq and the leading edge line 11a' is a leading edge point N1, and the angle between the line connecting 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 way 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 sinusoidal modulation equation is used to modulate the leading edge angle curve equation of the original impeller 10′, the resulting leading edge angle curve equation of the impeller 10 is the curve equation of the leading edge angle of the impeller 10. Based on the leading edge angle curve equation 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 determined offset amplitude of the leading edge 11d, the waveform of the leading edge 11d can be obtained.

[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 impeller 10 .

[0064] On a projection plane perpendicular to the rotation axis of impeller 10, the angle between the intersection of the projections of leading edge 11d and trailing edge 11e with the same tangent circle and the coordinate system origin is the wrap angle of impeller 10. The wrap angle will be further explained below, using 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 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 sinusoidal modulation equation is used to modulate the wrap angle curve equation of the original impeller 10′, 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, the serrations on the leading and trailing edges can break up the separated large vortices during the operation of the fan, 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 after the original impeller 12′ is modulated by 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 impeller 10 obtained after the original impeller 12′ is modulated by the sinusoidal modulation equation. With respect to this impeller 10, firstly, due to the formation of the airflow channel 11c, when the airflow passes through the blade 11, both the pressure-side and suction-side airflow can flow along the corresponding airflow channel 11c, resulting in a more uniform distribution of the airflow on the blade surface. This effectively handles the separation vortex on the blade surface, thereby reducing vortex noise. Secondly, because the airflow channels 11c formed by the wave crests 11a and the wave troughs 11b are staggered on opposite sides of the blade 11, the separation of the pressure-side and suction-side airflow at the trailing edge 11e can be staggered, thereby also reducing 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 sinusoidal modulation equation. 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 sinusoidal modulation equation. This allows the crest 11a and the trough 11b to extend smoothly from the leading edge 11d to the trailing edge 11e. Correspondingly, the direction of the airflow channel 11c is also smoother. This makes it easier to control the floating changes 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] Furthermore, for axial flow fans, the velocity distribution of the impeller dictates that negative pressure is greatest near the blade tips. Therefore, during operation, airflow tends to flow radially from the blade root to the blade tip. Axial flow fans in related art are unable to control airflow toward the blade tips, resulting in uneven airflow distribution across the blade surface and high noise levels.

[0072] When the impeller 10 of the present application is applied to an axial flow fan, since the airflow on the pressure side and the suction side can flow along the corresponding airflow channel 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 the waveform of the leading edge 11 d and the waveform of the trailing edge 11 e have a phase difference in the same coordinate system.

[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 an 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 exactly the same as the aforementioned slicing circle Fq. The multiple reference circles Ck may be equidistantly distributed or not. That is, the slicing circle Fq can be considered as equidistantly distributed reference circles 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, which allows the crest 11a and the trough 11b to 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 better reducing noise.

[0079] In one embodiment, please refer to Figure 1 and 2For an 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, the wave crest 11a and the wave trough 11b can both gradually deflect toward the direction close to the rotation axis Z from the leading edge 11d to the trailing edge 11e. In other words, from the leading edge 11d to the trailing edge 11e, the airflow channel 11c gradually deflects toward the direction close to the rotation axis Z. 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. This is equivalent to the airflow being deflected toward the direction close to the rotation axis Z under the guidance of the airflow channel 11c when flowing on the blade surface of the blade 11. As a result, the resistance to the airflow flow can be reduced, making the airflow flow smoother 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). Where y φ1 The equation of the leading edge angle curve of the original blade 11′ is represented by 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 dividing 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 means that 10 cutting circles Fq can 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 of the impeller 10 is Y θ2 In the equation, 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) 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 It 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 It 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 air flow channel 11c. The width mentioned here refers to the maximum width of the air flow channel 11c in the cross section.

[0091] For example, on the projection surface where the cutting circle Fq is located, the projection of the crest 11a and the projection of the adjacent 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] Each half wave band corresponds to one airflow channel 11c, and each wave band corresponds to two airflow channels 11c. One airflow channel 11c is formed by the wave crests 11a on the suction side, and the other airflow channel 11c is formed by the wave troughs 11b on the pressure side. In other words, at least two cutting circles Fq pass through the projected area of ​​each airflow channel 11c.

[0093] by Figure 4The original impeller 10' shown as an example, Figure 4 The projection plane in which the split circle Fq is located is the projection plane perpendicular to the rotation axis of the original impeller 10', when X max = 15, if there are two split circles Fq in each 1 / 2 wave band, the number of 1 / 2 wave bands is 7 (i.e. 15 = 2 x 7 + 1), which is equivalent to the total number of the suction side and the pressure side air flow passages 11c on the blade 11 of the modulated impeller 10 being 7. In addition, there is one extra split circle Fq which can define 0.5 air flow passages 11c, which is equivalent to the position of the extra split circle Fq being an incomplete air flow passage 11c.

[0094] Exemplarily, the sine modulation equation f(Q) can be: f(Q) = A x sin(0.5 x Q x π), wherein A represents the amplitude of the sine modulation equation.

[0095] More preferably, -2 ≤ A ≤ 2, and A is not equal to 0, in this value range, the wave peak 11a and the wave trough 11b can be smoothly transitioned, 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 positive, the offset amplitude of the leading edge 11d wave peak 11a point is A, and the offset amplitude of the leading edge 11d wave trough 11b point is -A, if A is negative, the offset amplitude of the leading edge 11d wave peak 11a point is -A, and the offset amplitude of the leading edge 11d wave trough 11b point is A, and the absolute value |A| of A is the depth of the air flow passage 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 positive, the offset amplitude of the trailing edge 11e wave peak 11a point is A, and the offset amplitude of the trailing edge 11e wave trough 11b point is -A, if A is negative, the offset amplitude of the trailing edge 11e wave peak 11a point is -A, and the offset amplitude of the trailing edge 11e wave trough 11b point is A, and the absolute value |A| of A is the depth of the air flow passage 11c at the trailing edge 11e.

[0099] Please refer to Figure 5 , Figure 5 The curve of the leading edge angle curve equation y φ1 = -47.346x + 11.705, and the curve of the leading edge angle curve equation Y φ2 of the impeller 10, wherein y φ1 = -47.346x + 11.705, the sine modulation equation f(Q) is: f(Q) = A x sin(0.5 x Q x π), and Y φ2 = y φ1 + f(X).

[0100] See also Figure 6 , Figure 6 The following is the equation y of the wrap angle curve 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 descriptions with reference to the terms "in one embodiment", "in some embodiments", "in other embodiments", "in further embodiments", or "exemplary" etc. mean 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 representations of the above terms do 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 features of different embodiments or examples, unless they are mutually inconsistent.

[0104] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application are intended to be within the scope of protection of the present application.

Claims

1. An impeller, characterized in that: include: A plurality of blades rotating about a rotation axis, the blades having a crest protruding from the suction side of the blade toward the pressure side of the blade and a trough recessed from the pressure side toward the suction side, the crest and the trough both extending 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 offset amplitude of the leading edge and the leading edge angle curve equation 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 offset amplitude and the wrap angle curve equation of the impeller obtained by modulating the original impeller with the sine modulation equation; Wherein, on a 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 connecting 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; the angle between the intersection of the projection of the leading edge and the projection of the trailing edge with the same tangent circle and the line connecting the origin of the coordinate system is the wrap angle; 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's wrap angle curve equation Y θ2 For: Y θ2 =y θ1 + f(X+k); where y φ1 The equation for the leading edge angle curve of the original impeller, 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.

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: 15≤X max ≤45; and / or, k=1.

5. The impeller according to claim 1 or 2, characterized in that: The width of each of the air flow channels is determined by the number of the cutting circles.

6. The impeller according to claim 5, 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 waveform projection, and there are at least two cutting circles in each 1 / 2 band.

7. 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.

8. The impeller according to claim 7, characterized in that -2≤A≤2, and A is not equal to 0.

9. 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.

10. A fan, characterized in that: The impeller comprises the impeller according to any one of claims 1 to 9.

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