Blower

Abstract

To provide a blower capable of improving performance. [Solution] According to the embodiment, the blower includes a bell mouth and an impeller. The bell mouth includes an opening. The impeller is provided in the opening. The impeller includes a blade portion including a leading edge. The impeller rotates. The leading edge includes a plurality of recesses. The plurality of recesses are arranged in the direction of rotation of the impeller.

Description

Technical Field

[0001] Embodiments of the present invention relate to a blower.

Background Art

[0002] There are blowers such as centrifugal blowers and axial flow blowers. In blowers, improvements in characteristics such as improvement of static pressure and reduction of noise are desired. At the leading edge of the blower blade and the curved surface of the volute, separation may occur, which may cause a decrease in static pressure due to an increase in fluid resistance, and generation of noise caused by pressure fluctuations due to generation and movement of vortices.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments of the present invention provide a blower capable of improving characteristics.

Means for Solving the Problems

[0005] According to an embodiment of the present invention, a blower includes a volute and an impeller. The volute includes an opening. The impeller is provided in the opening. The impeller includes blades including a leading edge. The impeller rotates. The leading edge includes a plurality of recesses. The plurality of recesses are arranged in the rotation direction of the impeller.

Brief Description of the Drawings

[0006] [Figure 1] FIG. 1 is a schematic view showing an example of a blower according to an embodiment. [Figure 2] FIG. 2 is a schematic view showing a part of a blower according to an embodiment. [Figure 3]Figure 3 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 4] Figure 4 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 5] Figure 5 is a schematic diagram showing a part of the blower according to the embodiment. [Figure 6] Figure 6 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 7] Figure 7 shows the characteristics of the blower according to the embodiment. [Figure 8] Figure 8 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 9] Figure 9 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 10] Figure 10 is a schematic diagram showing an example of a blower according to the embodiment. [Figure 11] Figure 11 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 12] Figure 12 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 13] Figure 13 shows the characteristics of the blower according to the embodiment. [Figure 14] Figure 14 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 15] Figure 15 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 16] Figure 16 shows the characteristics of the blower according to the embodiment. [Figure 17] Figure 17 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 18] Figure 18 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 19] Figure 19 is a schematic diagram showing a part of a blower according to an embodiment. [Figure 20] Figure 20 shows the characteristics of the blower according to the embodiment. [Modes for carrying out the invention]

[0007] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the ratio of the sizes between parts, etc. are not necessarily the same as the actual ones. Even when representing the same part, the dimensions and ratios may be represented differently in the drawings. In the specification of the present application and each figure, the same elements as those described above with respect to the previously shown figures are denoted by the same reference numerals, and detailed descriptions thereof are omitted as appropriate.

[0008] FIG. 1 is a schematic diagram showing an example of a blower according to an embodiment. As shown in FIG. 1, the blower 100 according to the embodiment includes a bellmouth 10 and an impeller 20. The bellmouth 10 includes an opening 11. The impeller 20 rotates about an axis A1.

[0009] FIG. 2 is a schematic diagram showing a part of the blower according to the embodiment. As shown in FIG. 2, the impeller 20 includes blade portions 21. The impeller 20 includes a plurality of blade portions 21a, 21b. The impeller 20 rotates, for example, in the rotational direction of the arrow shown in FIG. 2. The plurality of blade portions 21a, 21b are provided in the circumferential direction.

[0010] The impeller 20 includes a leading edge portion 22 and a trailing edge portion 25. The leading edge portion 22 extends from the trailing edge portion 25 toward the inside of the impeller 20. The leading edge portion 22 is the foremost edge of the blade portion 21 and is the portion that first encounters the air to be opposed. Each of the plurality of blade portions 21a, 21b includes a leading edge portion 22a, 22b and a trailing edge portion 25a, 25b.

[0011] As shown in FIGS. 1 and 2, the blower 100 according to the embodiment may be, for example, a centrifugal blower. As shown in FIG. 1, the air flows from the direction W1 of the arrow shown in FIG. 1 to the direction W2 of the arrow.

[0012] FIG. 3 is a schematic diagram showing a part of the blower according to the embodiment. Figure 4 is a schematic diagram showing a part of the blower according to the embodiment. The region P1 shown in Figure 3 is shown in Figure 4. As shown in Figures 3 and 4, the leading edge portion 22 includes a plurality of recesses 30. The plurality of recesses 30 are aligned in the rotational direction DR of the impeller 20.

[0013] It is known that a higher static pressure contributes to improved performance, such as that of a heat exchanger. By including multiple recesses 30 in the leading edge portion 22, it is possible to reduce air separation around the multiple recesses 30. This increases the static pressure. As a result, vortex generation due to pressure drop and separation of the air around the multiple recesses 30 is reduced, and the noise of the blower 100 is suppressed. This allows for improved performance.

[0014] Multiple recesses 30 can be riblets. The pitch of the riblets can be between 0.5 mm and 4.0 mm. This increases the static pressure, suppressing the pressure drop in the air around the multiple recesses 30 and reducing noise from the blower 100. This allows for improved performance.

[0015] The depth of the riblets can be between 0.2 mm and 2.0 mm. This increases the static pressure, further suppressing the pressure drop in the air around the multiple recesses 30 and the noise from the blower 100. This allows for improved performance.

[0016] As shown in Figures 3 and 4, the leading edge portion 22 includes a first portion 23 and a second portion 24. The second portion 24 extends from the first portion 23 in the direction of axis A1. The second portion 24 is the tip 22c of the wing portion 21. Multiple recesses 30 may be provided in the first portion 23. Multiple recesses 30 may be provided in part or all of the first portion 23.

[0017] Figure 5 is a schematic diagram showing a part of the blower according to the embodiment. Figure 6 is a schematic diagram showing a part of the blower according to the embodiment. The region P2 shown in Figure 5 is shown in Figure 6. As shown in Figures 5 and 6, the multiple recesses 30 may be provided in the second part 24. The multiple recesses 30 may be provided in part or all of the second part 24.

[0018] Figure 7 shows the characteristics of the blower according to the embodiment. The horizontal axis in Figure 7 represents the airflow Q1 (m³). 3 The graph shows the dynamics ( / h). The vertical axis shows the static pressure SP1 (Pa). Figure 7 shows the PQ characteristics. The solid line characteristic E1 corresponds to the first reference example in which there are no multiple recesses 30 on the leading edge portion 22. The dashed line characteristic E2 corresponds to an embodiment in which multiple recesses 30 are provided on the first part 23. The dashed line characteristic E3 corresponds to an embodiment in which multiple recesses 30 are provided on the second part 24. As shown in Figure 7, the static pressure SP1 of characteristics E2 and E3 is higher than that of characteristic E1. This is because air separation around the multiple recesses 30 is reduced. As a result, the pressure drop in the air around the multiple recesses 30 and the noise of the blower 100 are suppressed. This makes it possible to improve the characteristics.

[0019] Figure 8 is a schematic diagram showing a part of a blower according to an embodiment. Figure 9 is a schematic diagram showing a part of the blower according to the embodiment. Region P3 shown in Figure 8 is shown in Figure 9. As shown in Figures 8 and 9, the second part 24 includes a plurality of steps 40. The plurality of steps 40 may be recessed from the inside to the outside along the axis A1 direction of the impeller 20. In this way, the static pressure is increased, and the pressure drop of the air around the plurality of recesses 30 and the noise of the blower 100 are suppressed. This makes it possible to improve the characteristics. The plurality of steps 40 may be provided in part or all of the second part 24. Manufacturing the blade portion 21 including the plurality of steps 40 by mold is easier than manufacturing the blade portion 21 including the plurality of recesses 30 by mold.

[0020] Figure 10 is a schematic diagram showing an example of a blower according to the embodiment. As shown in Figure 10, the blower according to the embodiment may be, for example, an axial flow blower. The blower 100 according to the embodiment includes a bell mouth 10 and an impeller 20. The bell mouth 10 includes an opening 11. The impeller 20 includes a blade portion 21. The blade portion 21 includes a plurality of blade portions 21a, 21b. The plurality of blade portions 21a, 21b are arranged in the circumferential direction. Air flows from the direction W1 of the arrow shown in Figure 10 in the Y axis direction.

[0021] Figure 11 is a schematic diagram showing a part of a blower according to an embodiment. Figure 12 is a schematic diagram showing a part of the blower according to the embodiment. The region P4 shown in Figure 11 is shown in Figure 12. As shown in Figures 11 and 12, the leading edge 22 includes a plurality of recesses 30. The plurality of recesses 30 are aligned in the rotational direction DR of the impeller 20. The plurality of recesses 30 are provided at the tip 22c of the blade portion 21 in the rotational direction DR. In this way, the static pressure is increased, and the pressure drop of the air around the plurality of recesses 30 and the noise of the blower 100 are suppressed. This makes it possible to improve the characteristics. The plurality of recesses 30 may be provided on part or all of the leading edge 22.

[0022] Figure 13 shows the characteristics of the blower according to the embodiment. The horizontal axis in Figure 13 represents the airflow Q2 (m³). 3 The graph shows the dynamics ( / h). The vertical axis shows the static pressure SP2 (Pa). Figure 13 shows the PQ characteristics. The solid line characteristic E4 corresponds to the second reference example in which there are no multiple recesses 30 on the leading edge 22. The dashed line characteristic E5 corresponds to the embodiment in which multiple recesses 30 are provided on the leading edge 22. As shown in Figure 13, the static pressure SP2 of characteristic E5 is higher than that of characteristic E4. This is because air separation around the multiple recesses 30 is reduced. As a result, the pressure drop in the air around the multiple recesses 30 and the noise of the blower 100 are suppressed. This makes it possible to improve the characteristics.

[0023] The multiple recesses 30 may serve as riblets. The pitch and depth of the riblets are as described above.

[0024] The blade portion 21 of the blower 100 according to this embodiment may also be used as the blade portion of a wind turbine. Providing a plurality of recesses 30 on the leading edge of the wind turbine blade portion is expected to suppress the reduction in surrounding air pressure and wind turbine noise.

[0025] The blade portion 21 of the blower 100 according to this embodiment may also be used as the blade portion of a water turbine or pump. Providing a plurality of recesses 30 on the leading edge of the blade portion of a water turbine or pump is expected to suppress the reduction in surrounding water pressure and cavitation caused by the reduction in water pressure.

[0026] Figure 14 is a schematic diagram showing a part of a blower according to an embodiment. Figure 15 is a schematic diagram showing a part of the blower according to the embodiment. The region P5 shown in Figure 14 is shown in Figure 15. The blower 100 shown in Figures 14 and 15 is an example of a centrifugal blower. As shown in Figures 14 and 15, the opening 11 includes a curved surface 12. The curved surface 12 includes a plurality of irregularities 50. In Figure 14, the plurality of irregularities 50 are provided on the air intake side SI. The plurality of irregularities 50 may be provided on part or all of the curved surface 12.

[0027] The multiple indentations 50 can be dimples. The dimple pitch can be between 2.0 mm and 6.0 mm. This increases the static pressure, further suppressing the pressure drop in the air around the multiple indentations 30 and the noise from the blower 100. This allows for improved performance.

[0028] The dimple depth can be between 0.2 mm and 0.7 mm. This increases the static pressure, further suppressing the pressure drop in the air around the multiple recesses 30 and the noise from the blower 100. This allows for improved performance.

[0029] Figure 16 shows the characteristics of the blower according to the embodiment. The horizontal axis in Figure 16 represents the airflow Q3 (m³). 3The graph shows the dynamics ( / h). The vertical axis shows the static pressure SP3 (Pa). Figure 16 shows the PQ characteristics. The solid line characteristic E6 corresponds to the third reference example in which there are no multiple irregularities 50 on the curved surface 12. The dashed line characteristic E7 corresponds to the embodiment in which multiple irregularities 50 are provided on the curved surface 12. As shown in Figure 16, the static pressure SP3 of characteristic E7 is higher than that of characteristic E6. This is because air separation is reduced on the curved surface 12 of the outlet side SB. As a result, the noise of the blower 100 is suppressed by the reduction in vortex generation caused by the pressure drop and separation of air around the multiple recesses 30. This makes it possible to improve the characteristics.

[0030] Figure 17 is a schematic diagram showing a part of a blower according to an embodiment. The blower shown in Figure 17 is an example of an axial flow blower. As shown in Figure 17, the bell mouth 10 includes a base 10a and a rising section 10b. The opening 11 includes a curved surface 12. The curved surface 12 is located between the base 10a and the rising section 10b. Air flows from the direction of the arrow W1 to the direction of the arrow W2 shown in Figure 17. The curved surface 12 is provided on the outlet side SB.

[0031] Figure 18 is a schematic diagram showing a part of a blower according to an embodiment. Figure 19 is a schematic diagram showing a part of the blower according to the embodiment. Region P6 shown in Figure 18 is shown in Figure 19. As shown in Figures 18 and 19, the curved surface 12 includes a plurality of indentations 50. The plurality of indentations 50 are provided on the outlet side SB. The plurality of indentations 50 may be provided on part or all of the curved surface 12. The plurality of indentations 50 may be dimples. The pitch and depth of the dimples are as described above.

[0032] Figure 20 shows the characteristics of the blower according to the embodiment. The horizontal axis in Figure 20 represents the airflow Q4 (m³). 3 The graph shows the dynamics ( / h). The vertical axis shows the static pressure SP4 (Pa). Figure 20 shows the PQ characteristics. The solid line characteristic E8 corresponds to the fourth reference example in which there are no multiple irregularities 50 on the curved surface 12. The dashed line characteristic E9 corresponds to an embodiment in which multiple irregularities 50 are provided on the curved surface 12. As shown in Figure 20, the static pressure SP4 of characteristic E9 is higher than that of characteristic E8. This is because air separation is reduced on the curved surface 12 of the outlet side SB. As a result, the pressure drop in the air around the multiple recesses 30 and the noise of the blower 100 are suppressed. This allows for improved performance.

[0033] The bell mouth 10 of the blower 100 according to this embodiment may also be used as the wind lens of a wind turbine. Providing a plurality of recesses 30 on the curved surface of the wind lens of the wind turbine is expected to suppress the pressure drop of the surrounding air and the noise of the wind turbine.

[0034] The bell mouth 10 of the blower 100 according to this embodiment may also be used in the enclosure of a water turbine or pump. Providing a plurality of recesses 30 in the curved surface of the enclosure of a water turbine or pump is expected to suppress the decrease in surrounding water pressure and cavitation caused by the decrease in water pressure.

[0035] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configuration of each element, such as the bell mouth and impeller included in the blower, is included within the scope of the present invention as long as those skilled in the art can appropriately select from the known range to implement the present invention and obtain similar effects.

[0036] Furthermore, combinations of two or more elements from any of the specific examples, to the extent technically feasible, are also included within the scope of the present invention, insofar as they encompass the gist of the invention.

[0037] Furthermore, all blowers that a person skilled in the art can design and implement based on the blower described above as an embodiment of the present invention, insofar as they encompass the gist of the present invention, also fall within the scope of the present invention.

[0038] Furthermore, within the scope of the concept of the present invention, a person skilled in the art could conceive of various modifications and alterations, and it is understood that such modifications and alterations also fall within the scope of the present invention.

[0039] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0040] 10 Bell mouth, 10a Base, 10b Rising part, 11 Opening, 12 Curved surface, 20 Impeller, 21, 21a, 21b Blade section, 22, 22a, 22b Leading edge section, 22c Tip, 23 First section, 24 Second section, 25, 25a, 25b Trailing edge section, 30 Multiple recesses, 40 Multiple steps, 50 Multiple bumps and ridges, 100 blowers, A1 axis, DR rotation direction, SB discharge side, SI suction side

Claims

1. A bell mouth including an opening, An impeller is provided in the aforementioned opening and rotates, including a blade portion with a leading edge. Equipped with, The aforementioned leading edge portion includes a plurality of recesses, The aforementioned plurality of recesses are arranged in the direction of rotation of the impeller in a blower.

2. The aforementioned leading edge portion includes a first portion and a second portion extending axially from the first portion. The blower according to claim 1, wherein the plurality of recesses are provided in the first part.

3. The aforementioned leading edge portion includes a first portion and a second portion extending axially from the first portion. The blower according to claim 1, wherein the plurality of recesses are provided in the second part.

4. The blower according to any one of claims 1 to 3, wherein the plurality of recesses are riblets.

5. The pitch of the riblets is 0.5 mm or more and 4.0 mm or less. The blower according to claim 4, wherein the depth of the riblets is 0.2 mm or more and 2.0 mm or less.

6. The aforementioned blade portion includes a plurality of such blade portions, The blower according to claim 1, wherein the plurality of blades are arranged in the circumferential direction.

7. The aforementioned leading edge portion includes a first portion and a second portion extending axially from the first portion. The aforementioned second part includes multiple steps, The blower according to claim 1, wherein the plurality of steps recede in an inward direction from the inside to the outside along the axial direction of the impeller.

8. A bell mouth including an opening, An impeller is provided in the aforementioned opening and rotates, including a blade portion with a leading edge. The opening includes a curved surface, The aforementioned curved surface includes a plurality of bumps and irregularities, and is a blower.

9. The blower according to claim 8, wherein the plurality of protrusions are provided on the air intake side.

10. The blower according to claim 8, wherein the plurality of protrusions are provided on the air outlet side.

11. The blower according to claim 8, wherein the plurality of bumps and ridges are dimples.

12. The pitch of the dimples is 2.0 mm or more and 6.0 mm or less. The blower according to claim 11, wherein the depth of the dimple is 0.2 mm or more and 0.7 mm or less.

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