WO2020173372A1

WO2020173372A1 - Air conditioner indoor unit

Info

Publication number: WO2020173372A1
Application number: PCT/CN2020/075975
Authority: WO
Inventors: 赵鹏飞; 王洪新; 张强
Original assignee: 青岛海信日立空调系统有限公司
Priority date: 2019-02-28
Filing date: 2020-02-20
Publication date: 2020-09-03
Also published as: CN109667795B; CN109667795A

Abstract

An air conditioner indoor unit, comprising a housing (1), used for forming a cavity. An air inlet and an air outlet are provided on the housing (1). A heat exchanger is provided in the housing (1). A fan is provided in the housing (1). An airflow is introduced by the fan via the air inlet and then outputted through the heat exchanger via the air outlet. A fan current collector (3) comprises an annularly structured windward surface, the windward surface is provided with a protrusion (32) and/or a groove (31). The protrusion (32) and the groove (31) are used for disturbing a laminar flow boundary layer on the windward surface into a turbulent boundary layer. The air conditioner indoor unit is capable of increasing the efficiency of air intake and improves on the noise of air intake.

Description

Indoor unit of air conditioner

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on February 28, 2019, with application number 201 91 01 53408.5, and the title of the invention "a fan collector, centrifugal fan and air conditioning system", The entire content is incorporated into this application by reference.

Technical field

This application relates to the field of air conditioning technology, and in particular to an air conditioner indoor unit.

Background technique

The multi-blade centrifugal fan in the existing air conditioner, referring to Figure 1, includes a volute 001 with a hollow structure, the volute 001 has an air inlet end, the fan collector 003 is installed at the air inlet end, and the volute 001 is installed in the cavity The impeller 002, when the airflow enters the volute 001 through the fan collector 003, the high-speed rotating impeller 002 is used to accelerate the gas; among them, the fan collector 003 is an important part of the multi-blade centrifugal fan, and the fan collector 003 The air intake efficiency plays a decisive role in the performance of a multi-blade centrifugal fan. For example, as shown in Figure 1, the windward surface P1 of the fan collector 003 is a smooth surface. When the air flows through the smooth windward surface P1, it will cause The airflow forms a laminar boundary layer on the windward surface P1 (as shown in Figure 2), and the thickness of the laminar boundary layer is about 1%~1.5% of the radial dimension of the fan collector 003, which results in a flow along the fan In the radial direction of the collector 003, the airflow in the boundary layer has a very obvious flow velocity gradient, that is, the closer to the windward surface P1, the smaller the airflow velocity, or even zero, which will affect the air inlet efficiency of the fan collector 003. At the same time, when the airflow flows through the fan collector 003, the wind machine will make a low "humming" noise, or make a sharp noise, and the sound is not soft, which affects the comfort of the user experience.

Application content

The embodiment of the present application provides an indoor unit of an air conditioner, the main purpose of which is to effectively improve the air inlet efficiency of the fan collector and improve the sound quality of the air inlet noise. In order to achieve the foregoing objectives, the embodiments of the present application adopt the following technical solutions:

On the one hand, an embodiment of the present application provides a fan current collector, which includes a windward surface of an annular structure, and a protrusion and/or groove is formed on the windward surface, and the protrusion and the groove are used to The laminar boundary layer on the windward surface is disturbed into a turbulent boundary layer.

On the other hand, an embodiment of the present application provides a centrifugal fan, including:

A casing, the casing having an air inlet end and an air outlet end;

A fan current collector, the fan current collector being the fan current collector described in the above embodiment, the fan current collector being arranged at the air inlet end;

The impeller is arranged in the casing.

On the other hand, an embodiment of the present application provides an air conditioner indoor unit, including a casing for forming a cavity, and an air inlet and an air outlet are provided on the casing;

The heat exchanger is arranged in the shell;

And the centrifugal fan provided in the above embodiment.

In the fan collector, the centrifugal fan, and the indoor unit of the air conditioner provided by the embodiments of the present application, since the windward surface of the fan collector is formed with protrusions and/or grooves, the protrusions and/or grooves will make it close to the windward The airflow boundary layer on the surface forms a turbulent boundary layer due to the interference of the airflow disturbance structure. Compared with the laminar boundary layer, the turbulent boundary layer can reduce the resistance of the airflow on the windward surface and encourage the fan collector to suck more air. , And can reduce the gradient phenomenon formed by the air flow velocity, so that when the air flows through the windward surface, the flow velocity is more uniform, thereby improving the air inlet efficiency of the fan collector, and at the same time, widening the frequency bandwidth of the intake noise and reducing The tone of the intake noise ultimately improves the sound quality of the centrifugal fan.

Description of the drawings

Figure 1 is a schematic structural diagram of a centrifugal fan in the prior art; Figure 2 is an effect diagram of the laminar boundary layer formed when the air flows through the windward surface of the fan collector in the prior art;

FIG. 3 is a schematic structural diagram of a centrifugal fan provided by an embodiment of the application;

Figure 4 is a view from the direction A in Figure 3;

Figure 5 is a B-B cross-sectional view of Figure 4;

Fig. 6 is an enlarged view of C in Fig. 5;

FIG. 7 is a schematic diagram of a bump structure provided by an embodiment of the application;

Fig. 8 is a schematic structural diagram of another centrifugal fan provided by an embodiment of the application;

Fig. 9 is a view from the direction D of Fig. 8;

FIG. 10 is a schematic diagram of another protrusion structure provided by an embodiment of the application;

FIG. 11 is a schematic structural diagram of another groove provided by an embodiment of the application;

FIG. 12 is a schematic diagram of another protrusion structure provided by an embodiment of the application;

FIG. 13 is a schematic structural diagram of another groove provided by an embodiment of the application;

Fig. 14 is an effect diagram of the turbulent boundary layer formed when air flows through the windward surface of the fan header provided by the embodiment of the present application;

Fig. 15 is a comparison diagram of noise frequency spectrum between a fan current collector in the prior art and a fan current collector provided in an embodiment of the present application.

detailed description

The following describes in detail the fan collector, the centrifugal fan and the air conditioning system of the embodiments of the present application in conjunction with the accompanying drawings.

In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear",

"Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner", "Outer", etc. indicate the orientation or positional relationship: Based on the orientation or positional relationship shown in the drawings, it is only for the convenience of describing the application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood It is a restriction on this application.

The terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of these features. In the description of this application, unless otherwise stated, "plurality" means two or more.

3 to 7, an embodiment of the present application provides a fan current collector 3, including a ring-shaped windward surface F, the windward surface F is formed with protrusions 32 and/or grooves 31, protrusions 32 and recesses The groove 31 is used to disturb the laminar boundary layer on the windward surface F into a turbulent boundary layer.

Referring to Fig. 14, since a groove 31 is formed on the windward surface F, when the airflow enters the fan header 3 and flows through the windward surface F, a turbulent boundary layer will be formed near the windward surface F. If a turbulent boundary layer is formed , The airflow will not be stagnated on the wall of the windward surface F, on the contrary, it will have a certain flow velocity, and along the radial direction of the fan collector 3, it will not form an airflow layer with a large flow velocity gradient value (ie It will not appear that the airflow velocity value on the wall surface close to the windward surface F is very small. The closer to the center of the fan collector 3, the greater the airflow velocity value). Therefore, the interference effect of the groove 31 will cause the passage of the windward The flow velocity of the airflow on the surface F is more uniform, so that the fan collector can suck in more air and improve the air intake efficiency of the fan collector. The following experimental data verify the technical effects achieved by the fan current collector provided in this application:

The above is an experiment conducted under the same specifications and the same external environment for the fan collector. From the above experimental data, it can be seen that the windward surface with grooves can significantly increase the air intake, and the air intake efficiency is increased by 7% .

In the same way, when a protrusion 32 is formed on the windward surface F, when the airflow enters the fan collector 3 and flows through the windward surface F, under the action of the protrusion 32, a turbulent flow boundary is formed near the windward surface F Floor.

With reference to Figure 15 to analyze the fan noise of the fan collector provided by the embodiment of the application and the fan collector of the prior art (no air flow disturbance structure):

The black line in Fig. 15 represents the fan noise spectrum curve diagram using the fan current collector of the prior art. The low frequency noise is higher and the high frequency noise is lower. However, the fan using the fan current collector provided in the embodiment of the application is The noise spectrum graph (gray line) reduces mid- and low-frequency noise, increases high-frequency noise, and makes the tone softer, which improves user experience accordingly.

In some embodiments, the protrusion 32 includes a plurality of dot-shaped protrusions; in other embodiments, the groove 31 includes a plurality of pits, and the dot-shaped protrusions or pits form a dot-shaped disturbance structure.

8 and 9, the pits include multiple, and the multiple pits have multiple arrangements. For example, referring to FIG. 8, the multiple pits are divided into multiple dot groups (ie, pit groups), each The multiple recesses in the recessed point group are located on the same circle with the center axis of the windward surface F as the center; in addition, multiple recesses may also be arranged in other ways.

In the same way, the dot-shaped protrusions may also include multiple dot-shaped protrusions, and the plurality of dot-shaped protrusions may be divided into a plurality of dot-shaped protrusion groups. On the same circle with the center axis as the center.

In order to further improve the efficiency of air intake, referring to Fig. 9, in two adjacent pit groups, the pit in one pit group is the first pit, and the pit in the other pit group is the second pit. The connection between the first pit and the center of the circle The line and the line connecting the second concave point and the center of the circle are not on the same straight line. For example, the line between the concave point in the nth concave point group and the center of the circle is a straight line L1, but the line between the concave point in the n-1th concave point group or the n+1th concave point group and the center of the circle is There is an angle between the straight line L2, L1 and L2 (not collinear). If L1 and L2 are collinear, the turbulent boundary layer and the laminar boundary layer are alternately arranged on the windward surface F. Compared with all turbulent boundary layers, the wind inlet efficiency of the entire fan collector will be reduced.

In other embodiments, three adjacent pits in two adjacent pit groups are arranged in an isosceles triangle. Referring to FIG. 8, they are located in the same pit group (for ease of description, referred to as the nth pit). The distance between two adjacent pits in the dot group is s, and the pit in the n-1th pit group adjacent to the nth pit group is adjacent to and adjacent to the nth pit group The distance between the concave points is 1 /2s, and the technical effect achieved in this way is to further make the formed turbulent boundary layer uniform, and further improve the efficiency of the air inlet.

In the same way, in two adjacent dot-shaped protrusion groups, the dot-shaped protrusion in one dot-shaped protrusion group is the first dot-shaped protrusion, and the dot-shaped protrusion in the other dot-shaped protrusion group is the second Two point-shaped protrusions, the line between the first point-shaped protrusion and the center of the circle is not on the same straight line as the line between the second point-shaped protrusion and the center of the circle, and the technical effect achieved is the same as that of the above-mentioned concave point. I will not repeat them here.

The distance between two adjacent point-like groups (ie, multiple point-like protrusions on the same circle or multiple concave points on the same circle) ranges from 0.05 to O. lx, where x is the axis of the windward surface F If the distance between two adjacent point groups is too large, it will affect the formation of the turbulent boundary layer. If the distance between two adjacent point groups is too small, it will increase the airflow on the windward surface F. Flow resistance.

For example, the dot-shaped protrusion may be the structure shown in FIG. 10 and FIG. 12; for another example, the concave point may be the structure shown in FIG. 11 and FIG. 13; and for another example, the structure may be formed on the windward surface including The structures shown in Fig. 10, Fig. 12, Fig. 11 and Fig. 13 are arranged with dot-shaped protrusions and recesses spaced apart.

6, the groove 31 includes a plurality of annular grooves circumferentially arranged on the windward surface F. Referring to FIG. 7, the protrusion 32 includes a plurality of annular protrusions arranged circumferentially along the windward surface F, and the annular grooves or annular protrusions form an annular disturbance structure. A plurality of annular disturbance structures are arranged side by side along the axial direction of the fan current collector, and the distance between two adjacent annular disturbance structures ranges from 0.0 ⁵ to 0. I _X , X is the axial length of the windward surface F, if adjacent If the distance between two annular perturbation structures is too large, it affects the formation of a turbulent boundary layer. If the distance between two adjacent annular perturbation structures is too small, it will increase the flow resistance of the airflow on the windward surface F.

In some embodiments of the present application, each annular perturbation structure is a circular structure, that is, the central axis of the annular perturbation structure coincides with the central axis of the fan current collector to form a circular annular perturbation structure. During manufacturing and processing, the processing is convenient , Easy to implement.

In some embodiments of the present application, the annular protrusion may be the structure shown in FIG. 7; in some embodiments of the present application, the annular groove may be the structure shown in FIG. 6; in some embodiments of the present application Among them, the annular protrusion and the annular groove are arranged at intervals.

It should be noted that the grooves and pits provided in this embodiment are blind grooves and corresponding blind spots to prevent airflow from flowing from the windward side to the leeward side opposite to the windward side, so as to affect the wind collection of the current collector As a result, when the airflow passes through the windward surface F, a turbulent boundary layer will also be formed under the action of the concave point.

The cross section of the point-shaped disturbance structure and the ring-shaped disturbance structure is a semicircular structure or a polygonal structure. For example, the cross-section of the ring-shaped disturbance structure shown in FIG. 7 is a semicircular structure, and the point-shaped disturbance structure shown in FIG. 12 and FIG. 13 The cross section of the structure is a semicircular structure, and the cross section of the point-shaped disturbance structure shown in Figs. 10 and 11 is a triangle. In addition, the cross-sections of the point-shaped disturbance structure and the ring-shaped disturbance structure may also be rectangular or trapezoidal, and the cross-sectional structures of the point-shaped disturbance structure and the ring-shaped disturbance structure are not limited here.

In order to ensure that a turbulent boundary layer can be formed on the windward surface F, the protrusions 32 and/or the grooves 31 are vertically

The boundary layer thickness of the laminar boundary layer, _X is the axial length of the windward surface F, Re is the Reynolds number, and / is the airflow Disturbance structure height coefficient. The height of the protrusion 32 refers to the vertical distance between the highest point of the protrusion 32 and the windward surface F, and the height of the groove 31 refers to the vertical distance between the lowest point of the groove 31 and the windward surface F. If the height is too high, the airflow will be increased. If the flow resistance is too low, it will be like a smooth windward surface, forming a laminar boundary layer instead of a turbulent boundary layer.

In order to effectively improve the efficiency of the air intake, the value range of / is 0.8~1.1; in some embodiments of the present application,

The value range of / is 0.8~1.1; in some embodiments of the present application, /=1.0.

The height of the protrusion 32 and/or the groove 31 provided by the embodiment of the present application is a, which is obtained by first determining the thickness of the laminar flow boundary layer and then obtaining the protrusion 32 and/or the groove 31 according to the thickness 5 of the laminar flow boundary layer If the height is this way, the laminar boundary layer on the windward surface will be transformed into a turbulent boundary layer due to disturbance, so that the height a of the obtained protrusion 32 and/or groove 31 can more accurately cause the laminar boundary layer to interfere Into a turbulent boundary layer.

The fan current collector 3 can be a cylindrical current collector, a conical current collector, a circular arc current collector or a nozzle-shaped current collector. The specific type of fan current collector is not limited here, as long as the windward side Fan current collectors with air flow disturbance structures formed on F are all within the protection scope of the present disclosure.

Another aspect of the embodiments of the present application also provides a centrifugal fan. Referring to Figures 3, 4, 5 and 8, the centrifugal fan includes: a casing 1, a fan collector 3 and an impeller 2, and the casing 1 has an inlet Wind end and outlet end' The fan current collector 3 is the fan current collector provided in the above embodiment, and the fan current collector 3 is arranged at the air inlet end of the casing 1; the impeller 2 is arranged in the casing 1.

Since the centrifugal fan provided by the embodiment of the present application includes the fan collector provided in the above embodiment, when the airflow passes through the fan collector 3, under the action of the protrusion 32 and the groove 31, a turbulent flow boundary will be formed on the windward surface F The turbulent boundary layer will effectively improve the air intake efficiency of the fan collector, thereby increasing the air intake efficiency of the centrifugal fan. At the same time, due to the existence of the protrusion 32 or the groove 31, the centrifugal fan The noise emitted is soft, and the sound quality is effectively improved compared with the existing centrifugal fan, making the user sound comfortable, thereby improving user experience and comfort.

The casing 1 and the fan collector 3 may be an integral structure or a separate structure. For example, when the casing 1 and the fan collector 3 have a separate structure, the fan collector 3 includes a flow guide 33 And the installation portion 34, the guide portion 33 is connected to the installation portion 34, and the installation portion 34 is provided at the air inlet end of the casing 1 through a connector or other connection structure (for example, welding). The guide portion 33 and the mounting portion 34 can also be integrally formed.

In some embodiments of the present application, the casing 1 may be an injection molded part or a sheet metal part; similarly, the fan collector 3 may be an injection molded part or a sheet metal part; in addition, the casing 1 and The fan collector 3 can also be made of other materials.

The impeller 2 can be a multi-blade impeller or an impeller of other structure. The specific structure of the impeller 2 is not limited here.

Another aspect of the embodiments of the present application also provides an air conditioning system. The air conditioning system includes the centrifugal fan provided in the above embodiments. The air conditioning system includes an indoor unit and an outdoor unit connected to each other. The centrifugal fan is installed in the indoor unit.

Since the air-conditioning system includes the centrifugal fan provided in the above embodiment, and the centrifugal fan includes a fan collector, the fan collector includes a windward surface F with an annular structure, and the windward surface F is formed with protrusions 32 and/or grooves 31. The ridges 32 and the grooves 31 are used to disturb the laminar boundary layer on the windward surface F into a turbulent boundary layer. The bulge 32 and the groove 31 will cause the airflow boundary layer near the windward surface to form a turbulent boundary layer. Compared with the existing laminar boundary layer, the turbulent boundary layer can reduce the resistance of the airflow on the windward surface and encourage the fans to concentrate. The flow device sucks in more air, and can reduce the gradient formed by the air flow velocity, so that the flow velocity is more uniform when the air flows through the windward surface, thereby improving the air inlet efficiency of the fan collector, and at the same time, widening the air inlet Bandwidth of air noise It reduces the tone of the intake noise and ultimately improves the sound quality of the centrifugal fan.

In the description of this specification, specific features, structures, materials, or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

The above are only specific implementations of this application, but the protection scope of this application is not limited to this. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application. Should be covered within the scope of protection of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. An air conditioner indoor unit, characterized in that it comprises:

A housing, which is used to form a cavity, and the housing is provided with an air inlet and an air outlet;

The heat exchanger is arranged in the shell;

A centrifugal fan, arranged in the housing, the airflow is introduced through the air inlet by the centrifugal fan, and then sent out from the air outlet after passing through the heat exchanger;

The centrifugal fan includes:

A casing, the casing having an air inlet end and an air outlet end;

The impeller is arranged in the casing;

The fan current collector includes a windward surface with a ring structure, and protrusions and/or grooves are formed on the windward surface, and the protrusions and the grooves are used to disturb the laminar boundary layer on the windward surface Into a turbulent boundary layer.

2. An air conditioner indoor unit according to claim 1, wherein the protrusions comprise a plurality of point protrusions or a plurality of annular protrusions arranged along the axial direction of the windward surface;

The groove includes a plurality of pits or a plurality of annular grooves axially arranged along the windward surface.

3. An air conditioner indoor unit according to claim 2, and the fan current collector according to claim 2, wherein a plurality of the dot-shaped protrusions or a plurality of the concave points are divided into a plurality of Dot-shaped groups, where the plurality of dot-shaped protrusions or the plurality of concave points in each of the dot-shaped groups are located on the same circle centered on the center axis of the windward surface.

The air conditioner indoor unit according to claim 3, characterized in that, in two adjacent dot groups, the dot protrusion or the recess in one of the dot groups Is a first point-like structure, the point-like protrusions or the recesses in the other of the point-like groups are second point-like structures, and the line between the first point-like structure and the center of the circle and the first The line connecting the two-point structure and the center of the circle is not on the same straight line.

5. The air conditioner indoor unit according to claim 1, wherein the cross section of the protrusion and the recess is a semicircular structure or a polygonal structure.

6. An air conditioner indoor unit according to claim 1, wherein the protrusion and/or the

The sliding windward surface forms the boundary layer thickness of the laminar flow boundary layer, X is the axial length of the windward surface, is the Reynolds number, and / is the height coefficient of the airflow disturbance structure.