Anti-surge fans and air conditioners

Abstract

The present invention provides an anti-surge fan, including a volute and an impeller, wherein the volute forms an air outlet, the inner side of the volute includes a volute tongue, and the outer side of the volute includes a first arc portion and a straight portion close to the air outlet. The fan surge is mainly due to the periodic generation of vortexes inside the fan. In the technical solution, a specific design is made for the specific size of the volute. Due to the relative position and size of the volute and the impeller therein, the surge can be significantly reduced, which has a restrictive effect on the control of the airflow therein.

Description

Technical Field

[0001] The invention relates to the field of air conditioning equipment, and in particular to an anti-surge fan and an air conditioner. Background Art

[0002] Crossflow fans are widely used in indoor units of household air conditioners. Since they are used indoors, noise control is very important. If the noise is too loud, it will affect the user experience. Surge occurs frequently during the trial production of indoor units, and the noise associated with surge greatly affects people's comfort. However, there are currently no design methods and guidelines for preventing surge. Experimental studies have found that the structure of the a and b sections of the crossflow fan volute and the volute tongue spacing c have a significant impact on the severity of the fan surge. Summary of the invention

[0003] To solve at least one of the above problems, the present invention provides an anti-surge blower, including a volute and an impeller, wherein the volute forms an air outlet, the inner side of the volute includes a volute tongue, and the outer side of the volute includes a first arc portion and a straight portion close to the air outlet.

[0004] The fan surge is mainly due to the periodic generation of vortexes inside the fan. In this technical solution, the specific size of the volute is specifically designed. Due to the relative position and size of the volute and the impeller therein, the surge can be significantly reduced, which has a restrictive effect on the control of the airflow therein.

[0005] Preferably, the first arc portion and the straight portion are connected by a connection point, and the ratio w of the difference y between the distance L from the connection point to the center of the impeller and the impeller radius R to the impeller radius R is between 0.68 and 0.78, that is,

[0006] w=y / R=0.73±0.05, where y=LR.

[0007] When the w value is controlled between 0.68 and 0.78, internal turbulence can be reduced and vibration can be reduced.

[0008] Preferably, the impeller region opposite to the first arc-shaped portion constitutes an airflow passing zone, and the angle formed by the airflow velocity direction passing through the impeller blades in the airflow passing zone and the straight portion is the outlet attack angle β.

[0009] The maximum exit angle of attack is: β = 40°±2°.

[0010] When the outlet angle β is controlled between 38° and 42°, internal turbulence and vibration can be reduced.

[0011] Preferably, the outlet attack angle β is the angle formed by the tangent direction of the impeller blades in the airflow passage area and the straight portion.

[0012] Preferably, a vertical distance C from the inner wall of the volute tongue to the outer edge of the impeller is equal to 3.1 mm-3.5 mm.

[0013] Preferably, the volute tongue is connected to the air outlet via a second arc portion, which can make the transition smoother and reduce the degree of turbulence.

[0014] Preferably, w=0.73.

[0015] Preferably, β=40°.

[0016] When w = 0.73 and β = 40°, the turbulence is the lowest and the vibration is reduced to the greatest extent.

[0017] Preferably, the cross section of the air outlet (12) increases along the direction of air flow. Since the air pressure inside the air outlet is relatively high, in order to enable the device to transmit the air flow to a farther place and make the temperature inside the space more uniform, the air outlet is set to increase along the direction of air flow, at which time the air flow speed is increased, and the air flow is sent to a farther place.

[0018] The present application also provides an air conditioner, comprising a fan as described in any one of the above technical solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of the first arc portion, the straight portion and the connection point;

[0020] Figure 2 is the schematic diagram of the exit attack angle β;

[0021] Figure 3 It is a schematic diagram of the vertical distance from the inner wall of the volute tongue to the outer edge of the impeller.

[0022] Description of reference numerals:

[0023] Volute 1, first arc portion 11, air outlet 12, connection point 13, straight portion 121

[0024] Snail tongue 14, second arc portion 15;

[0025] Impeller 2, air flow passes through zone 21. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0027] In the first embodiment, a surge-proof fan is provided, comprising a volute 1 and an impeller 2, wherein the volute 1 forms an air outlet 12, and the inner side of the volute 1 comprises a volute tongue 14, and is characterized in that the outer side of the volute 1 comprises a first arc-shaped portion 11 and a straight portion 121 close to the air outlet 12. The surge of the fan is mainly due to the periodic generation of vortexes inside the fan, and in the present technical solution, a specific design is made for the specific size of the volute, and the relative position and size of the volute and the impeller therein can significantly reduce the surge, and has a restrictive effect on the control of the airflow therein.

[0028] On the basis of the above embodiment, the first arc portion 11 and the straight portion 121 are connected by a connection point 13, and the ratio w of the difference y between the distance L from the connection point 13 to the center of the impeller 2 and the radius R of the impeller 2 and the radius R of the impeller 2 is between 0.68 and 0.78, that is,

[0029] w=y / R=0.73±0.05, where y=LR.

[0030] When the w value is controlled between 0.68 and 0.78, internal turbulence can be reduced and vibration can be reduced.

[0031] like Figure 1 As shown, the first arc portion 11 is the arc portion at AB, the straight portion 121 is the portion shown as BC in the figure, the connecting point 13 is point B, the center of the impeller is point O, wherein L is the distance from point B to point O, that is, the length of BO, and the difference between the length of BO and the impeller radius R is y. According to simulation calculations, when the ratio of y to R is between 0.68 and 0.78, the degree of turbulence is the lowest, reducing surge.

[0032] In another embodiment, the outlet attack angle β is simulated, and the region of the impeller 2 opposite to the first arc portion 11 constitutes an airflow passing area 21, and the angle formed by the airflow velocity direction passing through the blades of the impeller 2 in the airflow passing area 21 and the straight portion 121 is the outlet attack angle β.

[0033] The maximum exit angle of attack is: β = 40°±2°.

[0034] When the outlet angle β is controlled between 38° and 42°, internal turbulence and vibration can be reduced.

[0035] like Figure 2 As shown in the figure, the area circled by the dotted line is the air flow passing area 21. Driven by the impeller, the air flow is controlled by the inner wall of BC, and the air flow moves outward from the space between the two. At this time, the angle between the gas flow direction and the straight portion 121BC is the outlet angle β. Controlling the outlet angle β to between 38° and 42° reduces the degree of turbulence and minimizes surge.

[0036] On the basis of the above technical solution, the outlet attack angle β is the angle formed by the tangent direction of the impeller 21 blades in the airflow passing area 21 and the straight portion 121 .

[0037] The outlet attack angle β can also be described as the angle between the tangent direction of the impeller 21 blade and the straight portion 121BC.

[0038] Through simulation, it can be known that the vertical distance C from the inner wall of the volute tongue 14 to the outer edge of the impeller 2 is equal to 3.1mm-3.5mm.

[0039] like Figure 3 As shown, the distance between the inner wall of the volute tongue 14 and the impeller closest to it will also affect the occurrence of turbulence. By simulating and setting this distance C to a specific distance, the turbulence level can be reduced to minimize surge.

[0040] In addition, the volute tongue 14 is connected to the air outlet 12 via a second arc portion 15. At this time, connecting them via the second arc portion can make the transition smoother and reduce the degree of turbulence.

[0041] In a specific embodiment, w=0.73 and β=40°.

[0042] When w = 0.73 and β = 40°, the turbulence is the lowest and the vibration is reduced to the greatest extent.

[0043] According to the specific parameter control given in the above embodiment, different forms of controlling surge can be obtained according to different combinations of specific parameters:

[0044] (1) An anti-surge fan, whose volute has the following parameters:

[0045] The first arc portion 11 and the straight portion 121 are connected by a connecting point 13, and the ratio w of the difference y between the distance L from the connecting point 13 to the center of the impeller 2 and the radius R of the impeller 2 and the radius R of the impeller 2 is between 0.68 and 0.78, that is,

[0046] w=y / R=0.73±0.05, where y=LR.

[0047] At the same time, the impeller 2 area opposite to the first arc portion 11 constitutes an airflow passage area 21, and the angle formed by the airflow velocity direction through the impeller 2 blades in the airflow passage area 21 and the straight portion 121 is the outlet angle β, wherein the maximum outlet angle is: β=40°±2°.

[0048] (2) An anti-surge fan, whose volute has the following parameters:

[0049] The first arc portion 11 and the straight portion 121 are connected by a connecting point 13, and the ratio w of the difference y between the distance L from the connecting point 13 to the center of the impeller 2 and the radius R of the impeller 2 and the radius R of the impeller 2 is between 0.68 and 0.78, that is,

[0050] w=y / R=0.73±0.05, where y=LR.

[0051] At the same time, the vertical distance C from the inner wall of the volute tongue 14 to the outer edge of the impeller 2 is equal to 3.1 mm.

[0052] (3) An anti-surge fan, whose volute has the following parameters:

[0053] The impeller 2 region opposite to the first arc portion 11 constitutes an airflow passage area 21, and the angle formed by the airflow velocity direction through the impeller 2 blades in the airflow passage area 21 and the straight portion 121 is the outlet angle β, wherein the maximum outlet angle β is: β=40°±2°.

[0054] At the same time, the vertical distance C from the inner wall of the volute tongue 14 to the outer edge of the impeller 2 is equal to 3.1 mm.

[0055] (4) An anti-surge fan, whose volute has the following parameters:

[0056] The first arc portion 11 and the straight portion 121 are connected by a connecting point 13, and the ratio w of the difference y between the distance L from the connecting point 13 to the center of the impeller 2 and the radius R of the impeller 2 and the radius R of the impeller 2 is between 0.68 and 0.78, that is,

[0057] w=y / R=0.73±0.05, where y=LR.

[0058] At the same time, the impeller 2 area opposite to the first arc portion 11 constitutes an airflow passing area 21, and the angle formed by the airflow velocity direction passing through the impeller 2 blades in the airflow passing area 21 and the straight portion 121 is the outlet attack angle β, wherein the maximum outlet attack angle is: β = 40° ± 2°

[0059] The vertical distance C from the inner wall of the volute tongue 14 to the outer edge of the impeller 2 is equal to 3.1 mm.

[0060] The anti-surge fan with the above-mentioned specific parameters adopts the ratio w of the difference y between the distance L from the connection point 13 to the center of the impeller 2 and the radius R of the impeller 2 and the radius R of the impeller 2, the outlet angle of attack β and the vertical distance from the inner wall of the volute tongue 14 to the outer edge of the impeller 2, a specific embodiment of the combination of these three parameters in pairs, and an anti-surge fan that meets the above three parameters at the same time.

[0061] In actual use, only one of the parameters may be changed in an anti-surge fan according to actual conditions to reduce costs.

[0062] In order to enable the anti-surge fan to deliver the internal airflow to a further distance, the cross-section of the air outlet 12 increases along the airflow direction. Since the air pressure inside the air outlet is relatively high, in order to enable the device to deliver the airflow to a further place and make the temperature inside the space more uniform, the air outlet is set to increase along the airflow direction, at which time the airflow speed is increased, and the airflow is delivered to a further location.

[0063] The present application also provides an air conditioner, comprising a fan as described in any one of the above technical solutions.

[0064] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. An anti-surge fan, comprising a volute (1) and an impeller (2), wherein the volute (1) forms an air outlet (12), and the inner side of the volute (1) comprises a volute tongue (14), characterized in that: The outer side of the volute (1) comprises a first arc-shaped portion (11) and a straight portion (121) close to the air outlet (12); The first arc-shaped portion (11) and the straight portion (121) are connected via a connection point (13), and a ratio w of a difference y between a distance L from the connection point (13) to the center of the impeller (2) and a radius R of the impeller (2) to the radius R of the impeller (2) is between 0.68 and 0.78; The region of the impeller (2) opposite to the first arc-shaped portion (11) constitutes an airflow passage area (21), and the angle formed by the velocity direction of the airflow passing through the impeller (2) blades in the airflow passage area (21) and the straight portion (121) is an outlet angle of attack β, wherein the maximum outlet angle of attack is: β = 40° ± 2°.

2. The fan according to claim 1, characterized in that: The outlet attack angle β is the angle formed by the tangent direction of the impeller (2) blades in the airflow passing zone (21) and the straight portion (121).

3. The fan according to claim 1, characterized in that: The vertical distance C from the inner wall of the volute tongue (14) to the outer edge of the impeller (2) is equal to 3.1 mm-3.5 mm.

4. The fan according to claim 3, characterized in that: The volute tongue (14) is connected to the air outlet (12) via a second arc-shaped portion (15).

5. The fan according to claim 1, characterized in that: w＝0 .73。 6. The fan according to claim 1, characterized in that: β＝40°。 7. The fan according to claim 1, characterized in that: The cross section of the air outlet (12) increases along the flow direction of the airflow.

8. An air conditioner, characterized in that: A fan comprising the fan described in any one of claims 1 to 7.

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