CN211449113U - Single-sided bladeless diffuser structure of centrifugal fan - Google Patents

Abstract

The utility model discloses a unilateral bladeless diffuser structure of a centrifugal fan, comprising a volute, an impeller rotatably arranged in the volute, and an air inlet communicated with the volute. A vaneless diffuser is fixed on one side wall, the vaneless diffuser corresponds to the position of the impeller, and the vaneless diffuser includes an annularly arranged side plate and two annular support plates, the side plates are The blades of the impeller are arranged together, and the two annular support plates are arranged concentrically, respectively fixed on the inner side of the side plate and fixed with the inner wall of the volute. The utility model forms a bladeless diffuser structure by fixing one side plate on the side wall of the volute through two annular support plates, which can initially decelerate the air with relatively large kinetic energy driven by the impeller, thereby improving the centrifugal fan performance. Static pressure and static pressure efficiency.

Description

Single-sided bladeless diffuser structure of centrifugal fan

technical field

The utility model relates to the technical field of centrifugal fans, in particular to a unilateral bladeless diffuser structure of a centrifugal fan.

Background technique

The structure of a traditional low-pressure centrifugal fan is shown in Figures 1 and 7, and mainly includes an air inlet (1), an impeller (2) and a volute (3).

For a high-pressure small-flow centrifugal fan, as shown in Figure 2, when the impeller (2) is at a large flow rate, the outlet velocity of the impeller (2) is relatively large and the dynamic pressure at the outlet is relatively large, so a rotating bladeless diffuser is installed at the outlet of the impeller (2). to reduce the airflow velocity; despite this, the outlet dynamic pressure has improved, but it is still larger.

Theoretical calculations and tests show that under the design conditions to large flow conditions, the outlet dynamic pressure of conventional low-pressure centrifugal fans accounts for 5-15% of the total pressure of the fan; the outlet dynamic pressure of conventional high-pressure centrifugal fans accounts for 10% of the total pressure of the fan. -25%.

In actual use, due to the sudden expansion of the outlet pipe, the dynamic pressure at the outlet is almost lost, so that the centrifugal fan has high full pressure and full pressure efficiency, while static pressure and static pressure efficiency are low. The main resistance of the pipe network system is the static pressure of the fan, so improving the static pressure and static pressure efficiency of the centrifugal fan is of great significance to the energy saving of the fan.

Utility model content

The utility model aims to solve one of the technical problems in the related art at least to a certain extent. Therefore, one purpose of the present utility model is to propose a centrifugal fan, by adding an optimized unilateral bladeless diffuser in the centrifugal fan, under the premise of not changing the existing processing conditions and technological level, more convenient The application of a unilateral bladeless diffuser improves the static pressure and static pressure efficiency of the centrifugal fan, and the manufacturing cost of the fan increases less.

The technical scheme of the present utility model is as follows:

A unilateral bladeless diffuser structure of a centrifugal fan comprises a volute, an impeller rotatably arranged in the volute and an air inlet communicated with the volute, and is fixed on a side wall of the volute close to the air inlet A vaneless diffuser, the vaneless diffuser corresponds to the position of the impeller, the vaneless diffuser includes an annularly arranged side plate and two annular support plates, the side plate is arranged in a fit with the blades of the impeller, The two annular support plates are concentrically arranged, respectively fixed on the inner side of the side plate and fixed with the inner wall of the volute.

Further, the impeller is a binary blade or a ternary blade.

Further, the impeller is a rotating vaneless diffuser or an impeller without a diffuser.

Further, the side plates are arranged vertically downward.

Further, the side plate is inclined toward the air inlet.

Further, the inclination angle α of the side plate is preferably 5°-15°.

The beneficial effect of the utility model is that one side plate is fixed on the side wall of the volute by two annular support plates to form a bladeless diffuser structure, which can initially decelerate the air with large kinetic energy driven by the impeller, Improve the static pressure and static pressure efficiency of centrifugal fans.

The utility model can be applied to a traditional two-element blade centrifugal fan, including backward-curved blades, radial blades and forward-curved blades, and can also be applied to a three-element blade centrifugal fan. Centrifugal fans without rotary vaneless diffusers can be applied as well as centrifugal fans with rotary vaneless diffusers.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the specification, and are used to explain the present invention together with the embodiments of the present invention, and do not constitute a limitation to the present invention. In the attached image:

Fig. 1 is the internal sectional schematic diagram of traditional centrifugal fan structure volute;

Fig. 2 is the internal sectional schematic diagram of the volute casing of the traditional centrifugal fan structure (with a rotating bladeless diffuser);

3 is a cross-sectional structural schematic diagram of the diffuser inside the volute of the centrifugal fan of the present invention (with a unilateral bladeless diffuser);

4 is a cross-sectional structural schematic diagram of the diffuser inside the volute of the centrifugal fan of the present invention (with a unilateral bladeless diffuser);

5 is a cross-sectional structural schematic diagram of the diffuser inside the volute of the centrifugal fan of the present invention (with a rotating bladeless diffuser, with a unilateral bladeless diffuser);

6 is a schematic cross-sectional structural diagram of the diffuser inside the volute of the centrifugal fan of the present invention (with a rotary vaneless diffuser and a unilateral vaneless diffuser).

Fig. 7 is the three-dimensional structure schematic diagram of the air inlet of traditional centrifugal fan and impeller;

FIG. 8 is a schematic three-dimensional structure diagram of FIG. 3 without a volute.

In the figure: 1-air inlet; 2-impeller; 3-volute; 4-side plate; 5-ring support plate.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the implementations. example.

Examples of such embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to be used to explain the present invention, but should not be construed as a limitation of the present invention.

3 and 8, a unilateral bladeless diffuser structure of a centrifugal fan includes a volute 3, an impeller 2 rotatably arranged in the volute 3, and an air inlet 1 communicating with the volute 3. 3. A bladeless diffuser is fixed on a side wall of the inner wall close to the air inlet 1, and the bladeless diffuser corresponds to the position of the impeller 2 (that is, the bladeless diffuser is set corresponding to the air inlet 1, and is arranged around the top of the impeller 2 On the side, the air discharged from the impeller after the air intake is buffered and decelerated by the unilateral bladeless diffuser). The blades of 2 are arranged (not in contact, with a certain gap), and the two annular support plates 5 are arranged concentrically, respectively fixed on the inner side of the side plate 4 and fixed with the inner wall of the volute 3. The setting of the bladeless diffuser can play the role of air flow buffer, avoid the large dynamic pressure loss caused by the sudden expansion of the large outlet pipe, and the static pressure conversion rate is low, which can reduce the airflow speed in the volute 3 and improve the static pressure of the centrifugal fan. pressure and hydrostatic efficiency. In addition, in FIG. 3, the side plate 4 is arranged vertically downward (parallel to the inner wall of the volute 3).

Referring to FIG. 4 , the side plate 4 is inclined toward the direction of the air inlet 1 , and the inclination angle α is preferably 5°-15°.

With further reference to Figures 5 and 6, the above-mentioned vaneless diffuser structure can be used for a vaneless diffuser with a rotation (a rotating vaneless diffuser is fixed at the end of the impeller blade, prior art), and can also be used for a traditional traditional diffuser. Diffuserless centrifugal fan. In addition, in addition to being applied to traditional binary blade centrifugal fans, such as backward curved blades, radial blades and forward curved blades, it can also be applied to ternary blade centrifugal fans.

By adding a vaneless diffuser, the airflow speed in the volute is reduced, and the static pressure and static pressure efficiency of the centrifugal fan are improved. Compared with the rotary vaneless diffuser, the unilateral vaneless diffuser is a unilateral diffuser and a fixed part, and the manufacturing cost is lower.

In this application, the structures and connection relationships that are not described in detail are all in the prior art, and the structures and principles thereof are already known in the art, such as the structure of a traditional centrifugal fan, and will not be repeated here.

The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited to this. Equivalent replacement or modification of the new technical solution and its utility model concept shall be included within the protection scope of the present utility model.

Claims (6)

1. a unilateral bladeless diffuser structure of a centrifugal fan, comprising a volute, an impeller that is rotated and arranged in the volute and an air inlet communicated with the volute, it is characterized in that: in the described volute, close to the air inlet A vaneless diffuser is fixed on a side wall of the blade, the vaneless diffuser corresponds to the position of the impeller, and the vaneless diffuser includes an annularly arranged side plate and two annular support plates. The side plates are arranged to fit the blades of the impeller, and the two annular support plates are arranged concentrically and are respectively fixed on the inner side of the side plates and fixed with the inner wall of the volute. 2 . The unilateral bladeless diffuser structure of a centrifugal fan according to claim 1 , wherein the impeller is a binary blade or a ternary blade. 3 . 3 . The unilateral bladeless diffuser structure of a centrifugal fan according to claim 2 , wherein the impeller is a rotating bladeless diffuser or an impeller without a diffuser. 4 . 4 . The unilateral bladeless diffuser structure of a centrifugal fan according to any one of claims 1 to 3 , wherein the side plates are arranged vertically downward. 5 . 5 . The unilateral bladeless diffuser structure of a centrifugal fan according to claim 1 , wherein the side plate is inclined toward the air inlet. 6 . 6 . The unilateral bladeless diffuser structure of a centrifugal fan according to claim 5 , wherein the inclination angle α of the side plate is 5°-15°. 7 .

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