Centrifugal fan volute for oil fume purification device

Abstract

The invention relates to a centrifugal fan volute for an oil fume purification device, which comprises a volute top plate (1), a volute bottom plate (3), a volute surrounding plate (2) and a volute flange (6), wherein an air inlet (11) is arranged on the volute top plate (1), an air outlet (61) is arranged on the volute flange (6), the plane located by the air outlet (61) is tilted to one side of the volute bottom plate (3) and not vertical to the plane located by the air inlet (11), volute tongues of the volute top plate (1) and the volute bottom plate (3) have asymmetric structures, the volute tongue of the volute top plate (1) has a wing-shaped head part and adopts the deep tongue form, the volute tongue of the volute bottom plate (3) has the wing-shaped head part and adopts the flat tongue form, and the volute surrounding plate (2) in the position of the volute tongues is used for connecting the two by the continuous smooth transition warped surface. The volute adopting the wing-shaped inclined volute tongues can greatly reduce the probability of producing flow separation and backflow in the position of the volute tongues, reduce the impact loss and be conductive to improving wind volume, wind pressure and efficiency of a centrifugal fan and reducing aerodynamic noise.

Description

technical field [0001] The invention relates to a centrifugal fan volute of an oil fume purification device, which belongs to the transformation technology of the centrifugal fan volute of the oil fume purification device. Background technique [0002] At present, oil fume purification equipment has become one of the essential kitchen equipment for ordinary families. Centrifugal fans have been widely used in oil fume purification equipment due to their advantages of large suction, low noise, and compact structure. Due to structural requirements, some oil fume purification equipment requires that the centrifugal fan used is one-sided air intake, and the outlet of the fan volute is inclined (that is to say, the plane where the volute air outlet is located is inclined toward the bottom plate of the volute, and is in line with the volute. The plane where the air inlet is located is not vertical), such as the near-suction hood with the fan below (see attached figure 1 ), bottom...

AI Technical Summary

Problems solved by technology

If a straight volute tongue is used, this uneven impeller outlet airflow cannot be taken into account

The sharp tongue is beneficial to the low-speed outlet airflow close to the front disk side of the impeller, which can greatly reduce the probability of backflow of this part of the airflow, but it is unfavorable to the high-speed outlet airflow near the rear disk side of the impeller, which will generate a lot of rotating noise

The use of a flat tongue is beneficial to the high-speed outlet airflow close to the rear disk side of the impeller, but it is unfavorable to the low-speed outlet airflow near the front disk side of the impeller. Backflow is easy to occur, and the air volume, air pressure and efficiency will drop sharply.

In addition, due to the inclination of the volute outlet, if a straight volute tongue is used, the impact loss of the airflow at the volute tongue will be large due to the unsmooth transition at the volute tongue, which will also reduce the air volume, wind pressure and efficiency and increase the noise.

[0004] The shape of the volute tongue has a great influence on the air volume, wind pressure, efficiency and noise of the centrifugal fan. The volute tongue designed by the traditional design method is prone to flow separation near the exit of the volute, forming a large reverse flow. pressure gradient, resulting in backflow, causing some gas to circulate in the volute, reducing the air volume, air pressure and efficiency of the fan, and increasing the eddy current noise

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