Mixed-flow fan and air duct machine

Abstract

The present invention discloses a mixed flow fan and a duct fan. The mixed flow fan comprises: an outer shell provided with an air inlet and an air outlet; an inner shell disposed within the outer shell, the outer shell and the inner shell forming an air duct connecting the air inlet and the air outlet; and an impeller, the hub of the impeller being rotatably disposed on the inner shell, the outer surface of the hub being connected to the outer surface of the inner shell to form a first guide surface. By improving the profile of the first guide surface, the mixed flow fan of the present invention can effectively increase the dynamic pressure of the airflow in the air duct, better convert the dynamic pressure into static pressure, increase the air output, and thus improve the performance of the mixed flow fan.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioners, and in particular to a mixed flow fan and a duct fan. Background Art

[0002] A ducted air conditioner is a type of air conditioner. In order to improve comfort, some ducted air conditioners use the method of discharging cold air from the top and hot air from the bottom, which can achieve waterfall-style cooling and carpet-style warm air. In order to achieve this air outlet method, the air outlet of the ducted air conditioner needs to be reversible. Among the existing ducted air conditioners with reversible air outlet, cross-flow fans and centrifugal fans are usually used. However, due to the problem of the setting method of the fan blades of this type of fan, the wind direction cannot be reversed after reversal. Therefore, at least two fans can only be set up, one for forward air outlet and the other for reverse air outlet. This will not only make the ducted air conditioner structure larger, but also cost higher.

[0003] To reduce costs, fans need to be smaller. Mixed-flow fans are a cross between axial-flow and centrifugal fans. Their impellers create both centrifugal and axial motion, creating a blend of axial and centrifugal airflow within the volute, hence the name "mixed flow." Furthermore, mixed-flow fans not only minimize size but also maintain consistent airflow direction and pressure.

[0004] In order to ensure the direction and pressure of the air flow, the air duct in the volute plays a very critical role. However, due to volume limitations, the space for setting up the air duct in the existing mixed flow fan is very limited. How to optimize the structure of the air duct under the premise of existing size limitations, effectively ensure the direction and pressure of the air flow, and improve the air supply efficiency of the mixed flow fan is an urgent problem to be solved in this field. Summary of the Invention

[0005] The invention discloses a mixed flow fan and an air duct fan, which solve the problem that the air supply effect of the existing mixed flow fan is limited due to volume restriction.

[0006] According to one aspect of the present invention, a mixed flow fan is disclosed, comprising: an outer shell provided with an air inlet and an air outlet; an inner shell disposed within the outer shell, wherein an air duct connecting the air inlet and the air outlet is formed between the outer shell and the inner shell; and an impeller, wherein a hub of the impeller is rotatably disposed on the inner shell, an outer surface of the hub is connected to an outer surface of the inner shell to form a first guide surface, wherein a first profile of the first guide surface is expressed as follows:

[0007]

[0008]

[0009] Among them, points P1 and P5 are the endpoints of the first profile, P3 is the inflection point of the first profile, P3 divides the first profile into a first curve and a second curve, P2 is the curvature control point of the first curve, and P4 is the curvature control point of the second curve; P1x represents the x-axis coordinate value of point P1, and P1y represents the y-axis coordinate value of point P1; P2x represents the x-axis coordinate value of point P2, and P2y represents the y-axis coordinate value of point P2; P3x represents the x-axis coordinate value of point P3, and P3y represents the y-axis coordinate value of point P3; P4x represents the x-axis coordinate value of point P4, and P4y represents the y-axis coordinate value of point P4; P5x represents the x-axis coordinate value of point P5, and P5y represents the y-axis coordinate value of point P5; the value range of t is 0≤t≤1.

[0010] Furthermore, P1x <P3x<P5x,P1y<P5y<P3y。

[0011] Furthermore, the inner wall surface of the shell forms a second flow-guiding surface, and the formula of the second profile of the second flow-guiding surface is:

[0012]

[0013]

[0014] Among them, points P8 and P12 are the endpoints of the two ends of the second profile, P10 is the inflection point of the second profile, P10 divides the second profile into a third curve and a fourth curve, P9 is the curvature control point of the third curve, and P11 is the curvature control point of the fourth curve; P8x represents the x-axis coordinate value of point P8, and P8y represents the y-axis coordinate value of point P8; P9x represents the x-axis coordinate value of point P9, and P9y represents the y-axis coordinate value of point P9; P10x represents the x-axis coordinate value of point P10, and P10y represents the y-axis coordinate value of point P10; P11x represents the x-axis coordinate value of point P11, and P11y represents the y-axis coordinate value of point P11; P12x represents the x-axis coordinate value of point P12, and P12y represents the y-axis coordinate value of point P12; the value range of t is 0≤t≤1.

[0015] Furthermore, P8x <P10x<P12x,P8y<P10y。

[0016] Furthermore, in the direction from the air inlet to the air outlet, the air duct includes a first area; the part of the first guide surface corresponding to the first curve is located in the first area, and the part of the second guide surface corresponding to the third curve is located in the first area, and the first area is used to convert the force driving the airflow into the dynamic pressure of the airflow.

[0017] Furthermore, the air duct also includes a second area, which is located between the first area and the air outlet; the part of the first guide surface corresponding to the second curve is located in the second area, and the part of the second guide surface corresponding to the fourth curve is located in the second area, and the second area is used to de-rotate the airflow and convert the dynamic pressure of the airflow into static pressure.

[0018] Furthermore, the mixed flow fan further includes: a flow collecting portion having a flow collecting channel communicating with the air duct, and the flow collecting portion is connected to the casing.

[0019] Furthermore, in the direction from the air inlet to the air outlet, the formula of the third profile of the inner wall of the collecting channel is:

[0020] B x (t) = (1-t) 2 P6 x +2t(1-t)P7 x +t 2 P8 x

[0021] B y (t) = (1-t) 2 P6 y +2t(1-t)P7 y +t 2 P8 y

[0022] Among them, points P6 and P8 are the endpoints of the third profile, and P7 is the curvature control point of the third profile; P6x represents the x-axis coordinate value of point P6, and P6y represents the y-axis coordinate value of point P6; P7x represents the x-axis coordinate value of point P7, and P7y represents the y-axis coordinate value of point P7; P8x represents the x-axis coordinate value of point P8, and P8y represents the y-axis coordinate value of point P8; the value range of t is 0≤t≤1.

[0023] Furthermore, P6x <P8x,P8y<P6y。

[0024] According to a second aspect of the present invention, a duct fan is disclosed, comprising the mixed flow fan described above.

[0025] The mixed flow fan of the present invention can effectively increase the dynamic pressure of the airflow in the air duct by improving the profile of the first guide surface, and better convert the dynamic pressure into static pressure, thereby increasing the air output and improving the performance of the mixed flow fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 1 is a structural diagram of a mixed flow fan according to an embodiment of the present invention;

[0027] Figure 2 Schematic diagram of the internal profile of the air duct of a mixed flow fan according to an embodiment of the present invention;

[0028] Legend: 10, outer shell; 11, air inlet; 12, air outlet; 13, air duct; 131, first area; 132, second area; 20, inner shell; 30, hub; 40, first guide surface; 41, first profile; 50, second guide surface; 51, second profile; 60, collecting part; 61, collecting channel; 62, third profile. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to the embodiments, but is not limited to the contents of the description.

[0030] like Figure 1 and Figure 2 As shown, the present invention discloses a mixed flow fan, including an outer shell 10, an inner shell 20 and an impeller. The outer shell 10 is provided with an air inlet 11 and an air outlet 12; the inner shell 20 is disposed in the outer shell 10, and an air duct 13 connecting the air inlet 11 and the air outlet 12 is formed between the outer shell 10 and the inner shell 20; the hub 30 of the impeller is rotatably disposed on the inner shell 20, and the outer surface of the hub 30 is connected to the outer surface of the inner shell 20 to form a first guide surface 40. The formula of the first profile 41 of the first guide surface 40 is:

[0031]

[0032]

[0033] Among them, points P1 and P5 are the endpoints of the first profile 41, P3 is the inflection point of the first profile 41, P3 divides the first profile 41 into a first curve and a second curve, P2 is the curvature control point of the first curve, and P4 is the curvature control point of the second curve; P1x represents the x-axis coordinate value of point P1, P1y represents the y-axis coordinate value of point P1; P2x represents the x-axis coordinate value of point P2, P2y represents the y-axis coordinate value of point P2; P3x represents the x-axis coordinate value of point P3, P3y represents the y-axis coordinate value of point P3; P4x represents the x-axis coordinate value of point P4, P4y represents the y-axis coordinate value of point P4; P5x represents the x-axis coordinate value of point P5, P5y represents the y-axis coordinate value of point P5; the value range of t is 0≤t≤1.

[0034] The mixed flow fan of the present invention can effectively increase the dynamic pressure of the airflow in the air duct 13 by improving the profile of the first guide surface 40, and better convert the dynamic pressure into static pressure, thereby increasing the air output and improving the performance of the mixed flow fan.

[0035] It should be noted that, when making a section along the plane where the impeller rotating shaft is located, the intersection line between the outer surface of the hub 30 and this section, and the intersection line between the outer surface of the inner shell 20 and this section form the first profile line 41 of the first flow guiding surface 40. Or, when orthographically projecting the hub 30 and the inner shell 20 onto the projection plane where the impeller rotating shaft is located respectively, the outer contour line of the projection is the first profile line 41 of the first flow guiding surface 40.

[0036] It should also be noted that t is an independent variable with a known range specific to the above curve, and its range is between 0 ≤ t ≤ 1. Only when the value of t is completely within this range can the formula draw a complete curve.

[0037] Furthermore, P1x < P3x < P5x and P1y < P5y < P3y. By making P1x < P3x < P5x and P1y < P5y < P3y, the first profile line 41 of the first flow guiding surface 40 can be made smoother, thereby reducing the flow channel resistance and improving the overall performance of the fan.

[0038] The inner wall surface of the outer shell 10 forms the second flow guiding surface 50, and the formula for the second profile line 51 of the second flow guiding surface 50 is:

[0039]

[0040]

[0041] Among them, the points P8 and P12 are the end points at both ends of the second profile line 51, P10 is the inflection point of the second profile line 51. P10 divides the second profile line 51 into a third curve and a fourth curve. P9 is the curvature control point of the third curve, and P11 is the curvature control point of the fourth curve; P8x represents the x-axis coordinate value of point P8, and P8y represents the y-axis coordinate value of point P8; P9x represents the x-axis coordinate value of point P9, and P9y represents the y-axis coordinate value of point P9; P10x represents the x-axis coordinate value of point P10, and P10y represents the y-axis coordinate value of point P10; P11x represents the x-axis coordinate value of point P11, and P11y represents the y-axis coordinate value of point P11; P12x represents the x-axis coordinate value of point P12, and P12y represents the y-axis coordinate value of point P12; the value range of t is 0 ≤ t ≤ 1.

[0042] It should be noted that, when making a section along the plane where the impeller rotating shaft is located, the intersection line between the inner wall surface of the outer shell 10 and this section forms the second profile line 51 of the second flow guiding surface 50. Or, when orthographically projecting the outer shell 10 onto the projection plane where the impeller rotating shaft is located, the inner contour line of the projection is the second profile line 51 of the second flow guiding surface 50.

[0043] It should also be noted that t is an independent variable with a known range specific to the above curve, and its range is between 0 ≤ t ≤ 1. Only when the value of t is completely within this range can the formula draw a complete curve.

[0044] Furthermore, P8x < P10x < P12x and P8y < P10y. By P8x < P10x < P12x and P8y < P10y, the second profile line 51 of the second flow guiding surface 50 can be made smoother, thereby reducing the flow channel resistance and improving the overall performance of the fan.

[0045] In the direction from the air inlet 11 to the air outlet 12, the air duct 13 includes a first region 131; the part of the first flow guiding surface 40 corresponding to the first curve is located within the first region 131, and the part of the second flow guiding surface 50 corresponding to the third curve is located within the first region 131. The first region 131 is used to convert the force driving the air flow into the dynamic pressure of the air flow. That is to say, the first curve and the third curve segment constitute the first region 131. The first region 131 is the internal flow domain of the moving blade, and this region is the working area of the fan. It can introduce the air flow in an axial flow manner and discharge it in a centrifugal form. In this way, both the air volume of the fan and the pressure-bearing capacity of the fan can be ensured.

[0046] The air duct 13 further includes a second region 132. The second region 132 is located between the first region 131 and the air outlet 12; the part of the first flow guiding surface 40 corresponding to the second curve is located within the second region 132, and the part of the second flow guiding surface 50 corresponding to the fourth curve is located within the second region 132. The second region 132 is used to deswirl the air flow and convert the dynamic pressure of the air flow into static pressure. That is to say, the second curve and the fourth curve constitute the second region 132. The second region 132 is the internal flow domain of the deswirl section and the guide vane. Deswirling can receive the high-speed air flow from the moving blade, guide it into the guide vane region, reduce the rotational speed of the air flow, and convert it into static pressure for delivery.

[0047] The mixed-flow fan of the present invention can obtain the internal flow channel curve of the mixed-flow fan according to the formula through the key nodes P1, P3, P5, P6, P7, P8, P9, P10, P11, and P12. Under the constraint of the internal flow channel, the fan can perfectly convert the dynamic pressure of the moving blade into static pressure, thereby improving the performance of the fan. A simulation test is carried out on the mixed-flow fan of this embodiment, and the connection form of adjacent key points is changed. The simulation results are as follows:

[0048] Key point connection form Speed (rpm) <![CDATA[Air volume (m 3 / s)]]> Fan static pressure efficiency Straight line connection 2200 406 42.4％ Formula curve connection 2200 510 60.2％

[0049] According to the simulation data, when the key points are connected in sequence using the formula curve, the area is the working area of the fan. The airflow enters in the form of axial flow and is thrown out in the form of centrifugal flow, which can not only ensure the air volume of the fan, but also ensure that the fan's pressure capacity and the fan static pressure efficiency are maximized. In addition, the air duct 13 can receive the high-speed airflow from the moving blades and guide it into the guide vane area, reducing the rotation speed of the airflow and converting it into static pressure for delivery. Therefore, the air volume and fan static pressure efficiency are the highest. When the key points are connected in sequence using straight lines, the airflow resistance is large and the derotation effect is reduced, so that the dynamic pressure of the airflow cannot be fully converted into static pressure, resulting in a decrease in the air volume and fan static pressure efficiency, reaching a state that cannot be used.

[0050] The mixed flow fan further includes a collecting portion 60 having a collecting channel 61 communicating with the air duct 13. The collecting portion 60 is connected to the housing 10. In the direction from the air inlet 11 to the air outlet 12, the formula of the third profile 62 of the inner wall of the collecting channel 61 is:

[0051] B x (t) = (1-t) 2 P6 x +2t(1-t)P7 x +t 2 P8 x

[0052] B y (t) = (1-t) 2 P6 y +2t(1-t)P7 y +t 2 P8 y

[0053] Among them, points P6 and P8 are the endpoints of the third profile 62, and P7 is the curvature control point of the third profile 62; P6x represents the x-axis coordinate value of point P6, and P6y represents the y-axis coordinate value of point P6; P7x represents the x-axis coordinate value of point P7, and P7y represents the y-axis coordinate value of point P7; P8x represents the x-axis coordinate value of point P8, and P8y represents the y-axis coordinate value of point P8; the value range of t is 0≤t≤1.

[0054] It should be noted that when a cross section is made along the plane where the impeller axis is located, the intersection line of the inner wall surface of the header 60 and the cross section forms the third profile line 62. Alternatively, the header 60 is orthographically projected onto the projection plane where the impeller axis is located, and the inner contour line of the projection is the third profile line 62.

[0055] It should also be noted that t is an independent variable within a known range specific to the above curve, and its range is between 0 ≤ t ≤ 1. Only when the value of t is completely within this range can the formula draw a complete curve. P6x < P8x < P10x < P12x, and P8y < P6y < P10y. By optimizing the third type of line 62, the intake condition of the air flow can be improved, and the performance of the fan can be enhanced.

[0056] According to the second aspect of the present invention, an air duct machine is disclosed, which includes the above-mentioned mixed-flow fan.

[0057] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the embodiments of the present invention. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is impossible to list all the embodiments here. Any obvious changes or variations derived from the technical solutions of the present invention still fall within the protection scope of the present invention.

Claims

1. A mixed flow fan, characterized in that: include: The housing (10) is provided with an air inlet (11) and an air outlet (12); an inner shell (20) disposed inside the outer shell (10), wherein an air duct (13) communicating with the air inlet (11) and the air outlet (12) is formed between the outer shell (10) and the inner shell (20); An impeller, wherein a hub (30) of the impeller is rotatably disposed on the inner shell (20), an outer surface of the hub (30) is connected to an outer surface of the inner shell (20) to form a first guide surface (40), and a first profile line (41) of the first guide surface (40) is represented by: Wherein, points P1 and P5 are the endpoints of the first profile line (41), P3 is the inflection point of the first profile line (41), P3 divides the first profile line (41) into a first curve and a second curve, P2 is the curvature control point of the first curve, and P4 is the curvature control point of the second curve; P1x represents the x-axis coordinate value of point P1, and P1y represents the y-axis coordinate value of point P1; P2x represents the x-axis coordinate value of point P2, and P2y represents the y-axis coordinate value of point P2; P3x represents the x-axis coordinate value of point P3, and P3y represents the y-axis coordinate value of point P3; P4x represents the x-axis coordinate value of point P4, and P4y represents the y-axis coordinate value of point P4; P5x represents the x-axis coordinate value of point P5, and P5y represents the y-axis coordinate value of point P5; The value range of t is 0≤t≤1.

2. The mixed flow fan according to claim 1, characterized in that P1x <P3x<P5x,P1y<P5y<P3y。 3. The mixed flow fan according to claim 1, characterized in that: The inner wall surface of the housing (10) forms a second flow-guiding surface (50), and the formula of the second profile line (51) of the second flow-guiding surface (50) is: Wherein, points P8 and P12 are the endpoints of the second profile line (51), P10 is the inflection point of the second profile line (51), P10 divides the second profile line (51) into a third curve and a fourth curve, P9 is the curvature control point of the third curve, and P11 is the curvature control point of the fourth curve; P8x represents the x-axis coordinate value of point P8, and P8y represents the y-axis coordinate value of point P8; P9x represents the x-axis coordinate value of point P9, and P9y represents the y-axis coordinate value of point P9; P10x represents the x-axis coordinate value of point P10, and P10y represents the y-axis coordinate value of point P10; P11x represents the x-axis coordinate value of point P11, and P11y represents the y-axis coordinate value of point P11; P12x represents the x-axis coordinate value of point P12, and P12y represents the y-axis coordinate value of point P12; The value range of t is 0≤t≤1.

4. The mixed flow fan according to claim 2, characterized in that: P8x <P10x<P12x,P8y<P10y。 5. The mixed flow fan according to claim 3, characterized in that: In the direction from the air inlet (11) to the air outlet (12), the air duct (13) includes a first area (131); The portion of the first guide surface (40) corresponding to the first curve is located in the first area (131), and the portion of the second guide surface (50) corresponding to the third curve is located in the first area (131). The first area (131) is used to convert the force driving the airflow into the dynamic pressure of the airflow.

6. The mixed flow fan according to claim 5, characterized in that The air duct (13) further includes a second area (132), and the second area (132) is located between the first area (131) and the air outlet (12); The portion of the first guide surface (40) corresponding to the second curve is located in the second area (132), and the portion of the second guide surface (50) corresponding to the fourth curve is located in the second area (132). The second area (132) is used to de-rotate the airflow and convert the dynamic pressure of the airflow into static pressure.

7. The mixed flow fan according to claim 3, characterized in that: The mixed flow fan further comprises: A collecting portion (60), the collecting portion (60) having a collecting channel (61) communicating with the air duct (13), and the collecting portion (60) being connected to the housing (10).

8. The mixed flow fan according to claim 7, characterized in that: In the direction from the air inlet (11) to the air outlet (12), the formula of the third profile line (62) of the inner wall of the collecting channel (61) is: B x (t)=(1-t) 2 P6 x +2t(1-t)P7 x +t 2 P8 x B y (t)=(1-t) 2 P6 y +2t(1-t)P7 y +t 2 P8 y Wherein, points P6 and P8 are the endpoints of the third profile line (62), and P7 is the curvature control point of the third profile line (62); P6x represents the x-axis coordinate value of point P6, and P6y represents the y-axis coordinate value of point P6; P7x represents the x-axis coordinate value of point P7, and P7y represents the y-axis coordinate value of point P7; P8x represents the x-axis coordinate value of point P8, and P8y represents the y-axis coordinate value of point P8; The value range of t is 0≤t≤1.

9. The mixed flow fan according to claim 8, characterized in that: P6x<P8x,P8y<P6y.

10. A ducted air conditioner, characterized in that: A mixed flow fan comprising the mixed flow fan according to any one of claims 1 to 9.

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