CN108087342A - A kind of centrifugal blower diffuser with helmholtz resonance noise elimination structure - Google Patents

Abstract

The invention relates to a centrifugal fan diffuser with a Helmholtz resonance noise elimination structure, which belongs to the technical field of noise elimination. It includes a Helmholtz resonance anechoic chamber, a volute, an intermediate ring, a diffuser seat and a gearbox; the volute is connected to the intermediate ring, and the diffuser seat is connected to the volute; the gearbox is connected to the volute and the diffuser The compressor seat is connected; the Helmholtz resonance and muffler chamber is arranged on the inner wall of the intermediate ring and/or the diffuser seat. The invention has simple, compact and reasonable structure, low manufacturing cost, and is suitable for use on high-speed centrifugal fans of all specifications; it can effectively reduce and suppress the frequency noise of the impeller of the centrifugal compressor, and reduces the overall noise of the centrifugal compressor.

Description

A Centrifugal Fan Diffuser with Helmholtz Resonant Noise Reduction Structure

technical field

The invention relates to a centrifugal fan diffuser with a Helmholtz resonance noise reduction structure, in particular to a device for reducing passing frequency noise of an impeller of a centrifugal fan, which belongs to the technical field of noise reduction.

Background technique

When the centrifugal fan is running, the speed of the impeller is usually as high as tens of thousands of revolutions per minute. The compression of the working gas by the impeller produces a noise of a specific frequency, which is called the impeller passing frequency (BPF: Blade Pass Frequency). Frequency is usually up to several thousand Hertz and is the main source of fan noise.

Contents of the invention

The object of the present invention is to overcome the above disadvantages, thereby providing a centrifugal fan diffuser with a Helmholtz resonance noise reduction structure, which has a simple structure and low cost.

The technical solution of the present invention is a centrifugal fan diffuser with a Helmholtz resonance noise reduction structure, including a Helmholtz resonance noise elimination chamber, a volute, an intermediate ring, a diffuser seat and a gear box; the volute The shell is connected with the intermediate ring, and the diffuser seat is connected with the volute; the gear box is respectively connected with the volute and the diffuser seat; the Helmholtz resonance and muffler chamber is arranged on the inner wall of the intermediate ring and/or the diffuser seat superior.

After the volute, the intermediate ring and the diffuser seat are enclosed, a gas circulation channel is formed.

The volute is fixedly connected with the intermediate ring through threads; the diffuser seat is fixedly connected with the volute through threads; and the gear box is fixedly connected with the volute and the diffuser seat through threads.

The Helmholtz resonance anechoic cavity includes a perforated panel, a honeycomb partition and a bottom plate; the honeycomb partition is arranged between the perforated panel and the bottom plate. The depth of the Helmholtz resonance anechoic cavity is 5-70mm.

Beneficial effects of the present invention: the present invention has a simple, compact and reasonable structure, low manufacturing cost, and is suitable for use on high-speed centrifugal fans of all specifications; it can effectively reduce and suppress the passing frequency noise of centrifugal compressor impellers, reducing the centrifugal Overall noise of the compressor.

Description of drawings

Fig. 1 is a schematic cross-sectional view of the present invention.

Fig. 2 is a schematic diagram of the structure of the Helmholtz resonance anechoic cavity.

Description of reference signs: 1. Helmholtz resonance anechoic cavity; 2. Volute; 3. Intermediate ring; 4. Diffuser seat; 5. Gear box; 6. Gas circulation channel; 7. Perforated panel; 8. Honeycomb partition; 9, bottom plate.

Detailed ways

As shown in Figure 1-2, a centrifugal fan diffuser with Helmholtz resonance structure, including Helmholtz resonance cavity 1, volute 2, intermediate ring 3, diffuser seat 4 and Gear box 5; the volute 2 is connected with the intermediate ring 3, and the diffuser seat 4 is connected with the volute 2; the gear box 5 is respectively connected with the volute 2 and the diffuser seat 4; the Helmholtz resonance elimination The acoustic cavity 1 is arranged on the inner wall of the intermediate ring 3 and/or the diffuser seat 4 .

After the volute 2 , the intermediate ring 3 and the diffuser seat 4 are enclosed, a gas circulation channel 6 is formed.

The volute 2 is fixedly connected with the intermediate ring 3 through threads; the diffuser seat 4 is fixedly connected with the volute 2 through threads; the gear box 5 is fixedly connected with the volute 2 and the diffuser seat 4 through threads.

The Helmholtz resonance anechoic cavity 1 includes a perforated panel 7 , a honeycomb partition 8 and a bottom plate 9 ; the honeycomb partition 7 is arranged between the perforated panel 6 and the bottom plate 8 .

The depth of the Helmholtz resonance anechoic cavity 1 is 5-70mm. The height of the blade body is 5 to 100 mm.

When the present invention is working, the centrifugal fan is running, and the noise propagates along the airflow direction. When it encounters the leading edge of the blade, it is reflected by the Helmholtz resonance anechoic chamber 1 to obtain a sound wave with the same frequency and opposite phase as the blade passes through, thereby canceling the noise. The noise on the passing frequency of some blades is reduced, and the overall noise level is reduced.

Claims (5)

1. a kind of centrifugal blower diffuser with helmholtz resonance noise elimination structure, it is characterized in that：Including helmholtz resonance Noise elimination cavity（1）, spiral case（2）, mesosphere（3）, diffuser seat（4）And gear-box（5）；The spiral case（2）With mesosphere（3）Even It connects, diffuser seat（4）With spiral case（2）Connection；Gear-box（5）Respectively with spiral case（2）With diffuser seat（4）Connection；The last of the twelve Earthly Branches nurse Hereby resonant silencing chamber suddenly（1）It is arranged at mesosphere（3）And/or diffuser seat（4）Inner wall on.

2. there is the centrifugal blower diffuser of helmholtz resonance noise elimination structure as described in claim 1, it is characterized in that：The snail Shell（2）, mesosphere（3）With diffuser seat（4）After surrounding, air ventilation passage is formed（6）.

3. there is the centrifugal blower diffuser of helmholtz resonance noise elimination structure as described in claim 1, it is characterized in that：The snail Shell（2）With mesosphere（3）It is threadably secured connection；Diffuser seat（4）With spiral case（2）It is threadably secured connection；Gear-box （5）With spiral case（2）With diffuser seat（4）It is threadably secured connection.

4. there is the centrifugal blower diffuser of helmholtz resonance noise elimination structure as described in claim 1, it is characterized in that：The last of the twelve Earthly Branches Mu Huozi resonant silencing chambers（1）Including perforated panel（7）, honeycomb partition plate（8）And bottom plate（9）；The honeycomb partition plate（8）It is arranged at Perforated panel（7）With bottom plate（9）Between.

5. there is the centrifugal blower diffuser of helmholtz resonance noise elimination structure as described in claim 1, it is characterized in that：The last of the twelve Earthly Branches Mu Huozi resonant silencing chambers（1）Depth be 5-70mm.