CN201606308U

CN201606308U - Volute housing of forward multi-wing centrifugal fan

Info

Publication number: CN201606308U
Application number: CN2009202724958U
Authority: CN
Inventors: 温选锋; 祁大同; 杨昕; 陈望明
Original assignee: Xian Jiaotong University; Guangdong Sunwill Precising Plastic Co Ltd
Current assignee: Xian Jiaotong University
Priority date: 2009-11-25
Filing date: 2009-11-25
Publication date: 2010-10-13
Anticipated expiration: 2019-11-25

Abstract

The utility model relates to a volute housing of a forward multi-wing centrifugal fan, comprising a volute plate, a guide ring positioned on the volute plate and an outlet positioned on the volute plate. The volute housing of the forward multi-wing centrifugal fan is characterized in that the guide ring is in a similar ellipse shape. By adopting the structure, the volute housing of the forward multi-wing centrifugal fan makes a compromise on the air inflow uniformity and the vorticity when an impeller is in a range close to the guide ring, the range satisfies the condition that the short radius of the ellipse guide ring is slightly less than or equal to the inside radius of the impeller, and the short radius is close to a volute tongue range, thereby the air inflow condition of the range is improved. The air inflow condition of a range far away from the volute tongue and close to the outlet of the volute housing is better, and reducing the vorticity and reducing the fan noise are taken as the principal things. Two different requirements can be conveniently satisfied through adjusting the position of the ellipse guide ring at the periphery of the volute housing, and since the vorticity of the impeller close to the guide ring range can be reduced and the uniformity of the airflow at the outlet of the guide ring at the peripheral direction can be improved, the noise can be effectively reduced, and the requirement of improving the performance of the fan can be satisfied.

Description

A kind of spiral case of forward multiple wing centrifugal blower fan

Technical field

The present invention relates to a kind of forward multiple wing blower fan, especially a kind of spiral case of forward multiple wing blower fan.

Background technique

Present prior art, as shown in Figure 1, a kind of multi-wing centrifugal fan spiral case comprises snail plate 1, be positioned at the duct ring 3 of snail plate 1 and be positioned at outlet 2 on the snail plate 1.General duct ring cross section is circle, and the duct ring diameter has three kinds of structures, and structure one is smaller or equal to profile ID; Structure two is between profile ID and external diameter; Structure three is more than or equal to impeller outer diameter.Because multi-blade fan duct ring 3 exit flows are very inhomogeneous in circumferential distribution, cause the impeller air inlet also inhomogeneous, it is better to export 2 regional inlet air conditions away from the snail tongue near spiral case, and relatively poor near spiral inlet area territory inlet air conditions, and impeller is bigger near near the eddy region duct ring 3, and the one of the main reasons of to be blower fan produce in this vortex middle and high audio-frequency noise.Structure one can reduce air-flow " leakage ", though can more effectively improve the utilization ratio of draught fan impeller to air-flow, bigger in impeller duct ring near zone vortex, be unfavorable for the reduction of fan noise; Though structure three can relatively effectively reduce near the eddy region of impeller duct ring, but air-flow is more serious through the phenomenon of duct ring and impeller clearance " leakage " time impeller inlet from impeller outlet simultaneously, and aggravated spiral case internal flow nonuniformity in the axial direction, caused the fan performance instability, problem such as efficient is low, noise is high and tonequality is not good; Structure two is to a certain degree being carried out the compromise consideration to the structure one and the pluses and minuses of structure three, but during structure two, duct ring does not fully take into account duct ring and exports the inhomogeneous effect that causes of circumferential air inlet, can not solve preferably inlet air conditions and strength of vortex this to contradiction, such as: the relatively poor zone of inlet air conditions, should be improving inlet air conditions, and local preferably at inlet air conditions, then to reduce eddy region and to reduce strength of vortex.Structure two can not effectively be taken into account and reduce strength of vortex and improve intake uniformity, makes impeller more inhomogeneous near flowing of spiral inlet area territory, has aggravated this regional strength of vortex, is unfavorable for the reduction of noise.

Summary of the invention

The objective of the invention is: a kind of spiral case of forward multiple wing centrifugal blower fan is provided, and it not only can improve the circumferential nonuniformity of duct ring exit flow, but also can reduce impeller near duct ring zone strength of vortex problem, reaches to effectively reduce noise.

The present invention is achieved in that a kind of spiral case of forward multiple wing centrifugal blower fan, comprises the snail plate, is positioned at the duct ring on the snail plate and is positioned at outlet on the snail plate, and its special way is: described duct ring is the class ellipse.

The spiral case of described a kind of forward multiple wing centrifugal blower fan, its special way is: described duct ring is a perpendicular ellipse and is rotated counterclockwise a θ dihedral, and the angle of major semi axis and Y-axis is θ; Major semi axis one end is near the exit region on the snail plate, and semi-minor axis one end is near the spiral inlet area territory of snail plate.

The spiral case of described a kind of forward multiple wing centrifugal blower fan, its special way is: described θ is 0 °-30 °.

The spiral case of a kind of forward multiple wing centrifugal blower fan of the present invention, owing to adopt such structure, in close spiral inlet area territory, inlet air conditions is relatively poor herein, should be to improve the air-flow utilization ratio, to make the mobile master that is more preferred from, and at inlet air conditions preferably away from the spiral inlet area territory, should be to reduce eddy region and strength of vortex, oval duct ring can be taken into account the requirement of this two aspect.The short radius of oval duct ring is slightly less than or equals the impeller inside radius, the close spiral inlet area territory of short radius, thereby improved this regional inlet air conditions, thus improve draught fan impeller reduces the duct ring back side simultaneously to the utilization ratio of air-flow strength of vortex; And away from the snail tongue near the spiral case exit region, this regional inlet air conditions is better, should reduce the blower fan fan noise of making an uproar to reduce strength of vortex, and oval duct ring major semi axis is slightly less than the impeller inside radius, make semi major axis near this zone, can reduce eddy region and strength of vortex.Satisfy following two kinds of different demands by regulating oval duct ring easily at the spiral case circumferential position: the demand that improves the demand of air quantity under the prerequisite that noise decreases by a relatively large margin and under the prerequisite that performance increases, effectively reduce noise.When needs improve air quantity by a relatively large margin, can make the major axis and the impeller outlet plane parallel of duct ring, when the duct ring major axis rotates about the 30 ° demands that can satisfy effective reduction noise to the spiral case outlet.

Described duct ring shape can be ellipse or class ellipse.

The utility model is compared the good effect that is produced with background technique:

1, owing to can reduce the close duct ring zone strength of vortex of impeller and improve the duct ring exit flow,, reaches the requirement that improves fan performance simultaneously so can effectively reduce noise in circumferential uniformity.

Description of drawings

Fig. 1 is the plan view of prior art.

Fig. 2 is the plan view of first kind of mode of execution of the utility model.

Fig. 3 is the plan view of second kind of mode of execution of the utility model.

Fig. 4 is one of stereogram of the present utility model.

Fig. 5 is two of a stereogram of the present utility model.

Fig. 6 is the utility model and prior art A sound level comparison diagram.

Fig. 7 is the utility model and prior art flow comparison diagram.

Fig. 8 is the utility model and prior art power comparison diagram.

Embodiment

Below in conjunction with accompanying drawing the utility model is further described.

Embodiment 1

As shown in Figure 2, a kind of spiral case of forward multiple wing centrifugal blower fan comprises snail plate 1, be positioned at the duct ring 3 of snail plate 2 and be positioned at outlet 2 on the snail plate, and described duct ring 3 is the class ellipse, and the center of duct ring 3 overlaps with the impeller center.

Oval major semi axis on the Y-axis, semi-minor axis on X-axis, be referred to as perpendicular oval, otherwise be referred to as horizontal oval;

Embodiment 2

As shown in Figure 3, described duct ring 3 is horizontal oval.

Embodiment 3

As Fig. 4, shown in Figure 5, a kind of multi-wing centrifugal fan spiral case comprises snail plate 1, be positioned at the duct ring 3 of snail plate 2 and be positioned at outlet 2 on the snail plate, and described duct ring 3 is the class ellipse, and the center of duct ring 3 overlaps with the impeller center.The major semi axis 5 and the Y-axis of described duct ring 3 have an angle theta, and major semi axis 5 one ends are near outlet 2 zones on the snail plate 1, and semi-minor axis 4 one ends are near snail tongue 6 zones of snail plate 1; Can say that also described duct ring 3 is a perpendicular ellipse and rotates counterclockwise several angle shape.

The spiral case of a kind of forward multiple wing blower fan of the utility model, the major semi axis 5 of described duct ring 3 is slightly less than the impeller outer radius, and the major semi axis 5 and the Y-axis of described duct ring 3 have an angle theta, and scope is 0 °-30 °;

Or the semi-minor axis 4 of described duct ring 3 is slightly less than or equals the impeller inside radius; The major semi axis 5 and the Y-axis of described duct ring 3 have an angle theta, and scope is 0 °-30 °,

As another kind of description form of the present utility model: described duct ring 3 is a horizontal ellipse and clockwise rotates several angle shape.

Claims

1. the spiral case of a forward multiple wing centrifugal blower fan comprises the snail plate, is positioned at the duct ring on the snail plate and is positioned at outlet on the snail plate that it is characterized in that: described duct ring is the class ellipse.

2. the spiral case of a kind of forward multiple wing centrifugal blower fan according to claim 1 is characterized in that: described duct ring is a perpendicular ellipse and is rotated counterclockwise a θ dihedral, and the angle of major semi axis and Y-axis is θ; Major semi axis one end is near the exit region on the snail plate, and semi-minor axis one end is near the spiral inlet area territory of snail plate.

3. the spiral case of a kind of forward multiple wing centrifugal blower fan according to claim 2 is characterized in that: described θ is 0 °-30 °.