阅读说明：本技术 一种离心通风机的叶轮 (Impeller of centrifugal ventilator ) 是由 裘霖富 徐天赐 张职锋 马杰凯 俞晓骏 刘伟 于 2019-10-12 设计创作，主要内容包括：本发明公开了一种离心通风机的叶轮,包括前盘、后盘以及设置在所述前盘和后盘之间的弧形叶片,其叶片外缘为弧线状,由多段弧线复合而成；同时对叶片外缘处和叶片内缘处的非工作面进行了倒角处理,提高了通风机的性能和效率。(The invention discloses an impeller of a centrifugal ventilator, which comprises a front disk, a rear disk and arc-shaped blades arranged between the front disk and the rear disk, wherein the outer edges of the blades are arc-shaped and are formed by compounding a plurality of sections of arcs; meanwhile, chamfering processing is carried out on the non-working surfaces at the outer edge of the blade and the inner edge of the blade, and the performance and the efficiency of the ventilator are improved.)

1. the utility model provides an impeller of centrifugal fan, is in including preceding dish, back plate and setting arc blade between preceding dish and the back plate, its characterized in that, the blade outer fringe is for being formed by the multistage pitch arc is compound, the blade external diameter PhiD that the extreme point that the blade outward flange leaned on the front plate side corresponds₂₁is larger than the outer diameter phi D of the blade corresponding to the end point close to the rear disc side₂₂And a line connecting both the end points has an inclination angle theta with respect to the impeller center line.

2. The impeller of claim 1, wherein the outer edge of the blade includes at least three arcs, wherein the arcs at two ends of the outer edge of the blade are convex in a direction away from the center line of the impeller, and the arcs in the middle of the outer edge of the blade are convex in a direction close to the center line of the impeller.

3. The impeller according to claim 1, characterized in that the outlet mean diameter of said blades is phid_2m，Whereink＝50～80。

4. the impeller of claim 1 having a blade exit width of b₂The inclination angle theta of the connecting line of the two end points of the composite arc line of the outer edge of the blade relative to the central line of the impeller is as follows:

5. The impeller of claim 1, which isIs characterized in that the outer edge of the blade is formed by compounding three sections of circular arcs, and the radius of the circular arc close to one side of the front disk is as follows:The arc radius in the middle is: r_m＝(1.3～1.5)×R₁(ii) a The radius of the circular arc close to one side of the rear disc is as follows: r₂＝(0.3～0.4)×R₁。

6. The impeller of claim 1, wherein the blade inner edge is chamfered to a wall thickness less than the blade body wall thickness, the chamfer being located on the concave surface of the cambered blade.

7. The impeller as claimed in claim 1, wherein the outer diameter of the blade is chamfered to have a wall thickness smaller than that of the blade body, and the chamfer is formed on the concave surface of the arc-shaped blade.

Technical Field

the invention relates to the technical field of ventilators, in particular to an impeller of a centrifugal ventilator.

Background

When the centrifugal ventilator is in normal operation, the airflow generates vortices when passing the trailing edge of the blade, and these vortices periodically shed from the trailing edge of the blade, which can affect the efficiency of the ventilator and also generate noise. In general, the projection of the meridian plane view of the edge of the outer diameter outlet of the blade (mostly perpendicular to the plane of the main body of the rear disk) of the centrifugal fan impeller is a straight line segment parallel to the central axis of the impeller, and the length of the straight line segment is the width of the outlet of the impeller, namely, the radius of the outer edge of the blade relative to the axis center is equal everywhere from the front disk side to the rear disk side. In operation of a rear-facing centrifugal fan wheel, the distribution of the air flow velocity at its outlet in the axial direction from the front disk side to the rear disk side is not completely uniform in general terms. The impellers with the same radius relative to the axis at all positions on the outer edge of the blade can better adapt to the non-uniformity of the airflow speed at the outlet of the blade in the axial direction, so that the efficiency of the ventilator is increased, and the noise is reduced.

Disclosure of Invention

The invention discloses an impeller of a centrifugal ventilator, wherein the outer edge of a blade is formed by compounding a plurality of sections of arc lines, the invention carries out refined design and improved comparison on the parameters of the whole arc line of the outer edge of the blade, the shape of each section of arc line, the radius of the arc line and the like, and simultaneously carries out chamfering treatment on non-working surfaces at the outer diameter and the inner diameter of the blade, so that the pressure and the efficiency of the ventilator are improved to a certain degree. .

The invention is realized by the following technical scheme:

The utility model provides an impeller of centrifugal fan, includes front bezel, back plate and sets up the arc blade between front bezel and back plate, and the blade outer fringe is formed for being compounded by the multistage pitch arc, the blade external fringe leans on the blade external diameter PhiD that the extreme point of front bezel side corresponds₂₁Is larger than the outer diameter phi D of the blade corresponding to the end point close to the rear disc side₂₂And a line connecting both the end points has an inclination angle theta with respect to the impeller center line.

Furthermore, the outer edge of each blade at least comprises three sections of arc lines, wherein the arc lines at two ends of the outer edge of each blade are respectively protruded towards the direction far away from the central line of the impeller, and the arc line in the middle is protruded towards the direction close to the central line of the impeller.

Further, the average diameter of the outlet of the blade is phi D_2m，Whereink＝50～80。

Further, the outlet width of the blade is b₂The inclination angle theta of the connecting line of the two end points of the composite arc line of the outer edge of the blade relative to the central line of the impeller is as follows:

Further, the outer edge of the blade is formed by compounding three sections of circular arcs, and the radius of the circular arc close to one side of the front disc is as follows:The arc radius in the middle is: r_m＝(1.3～1.5)×R₁(ii) a The radius of the circular arc close to one side of the rear disc is as follows: r₂＝(0.3～0.4)×R₁. Furthermore, chamfering processing is carried out on the inner edge of the blade, so that the wall thickness of the inner edge of the blade is smaller than that of the main body of the blade, and the chamfer is positioned on the concave surface of the arc blade.

Furthermore, chamfering processing is carried out on the outer diameter of the blade, so that the wall thickness of the outer diameter of the blade is smaller than that of the blade main body, and the chamfer is located on the concave surface of the arc-shaped blade.

The invention has the beneficial effects that:

The composite arc line of the outer edge of the blade of the invention is based on the non-uniformity of the air flow speed of the outlet of the impeller of the centrifugal ventilator, namely when the centrifugal ventilator runs in a small flow interval, the main air flow at the outlet is obviously deviated to one side close to the front disk, and the axial width of the main air flow gradually expands to the rear disk side along with the continuous increase of the flow of the ventilator, and even fills the whole outlet width interval. This causes cross-talk and friction between the outlet air streams, which results in flow losses, which in turn reduces the fan outlet pressure and fan aerodynamic efficiency, and produces additional outlet air stream secondary noise. In order to adapt to the uneven distribution of the airflow speed at the outlet of the impeller of the centrifugal ventilator, the outer edge of the blade is improved, the shape and the specific size of a more reasonable compound arc line of the outer edge of the blade are obtained through repeated design and analysis comparison, the flow difference of each part of the outlet of the blade along the axial direction is adapted to a certain extent, and the flow loss caused by the pressure gradient of the outlet of the blade along the axial direction is reduced.

The improved vane having an outlet edge that is the compound camber line of the present invention, in which the average vane outer diameter and the vane outlet width are maintained constant relative to conventional vanes having straight outer edges, increases the ventilator pressure by redistributing the area of the vane outlet at axially different localized positions in the vane outlet area while reducing the total area of the vane deployment, and reduces the flow loss at the vane outlet to a certain extent, thereby increasing the ventilator efficiency.

Drawings

FIG. 1 is a schematic view of a centrifugal fan according to an embodiment of the present invention;

FIG. 2 is a meridional cross-sectional view of an impeller of an embodiment of a centrifugal fan of the invention;

FIG. 3 is an arc of a vane of the peripheral surface of an impeller in accordance with an embodiment of the centrifugal fan of the present invention;

FIG. 4 is an enlarged view of portion I of FIG. 3 according to the present invention;

FIG. 5 is an enlarged view of section II of FIG. 3 according to the present invention;

FIG. 6 is a pressure comparison graph of example 1 of the present invention and comparative sample 1;

FIG. 7 is a graph showing the comparison of the efficiency of example 1 of the present invention and comparative sample 1;

FIG. 8 is a pressure comparison graph of example 2 of the present invention and comparative sample 2;

FIG. 9 is a graph comparing the efficiency of example 2 of the present invention with that of comparative sample 2.

In the figure, the position of the upper end of the main shaft,

1. the air inlet comprises an air inlet, 2. an impeller, 3. a motor, 21. a front disc, 22. blades, 23. a rear disc, 222. a chamfer angle at the outer diameter of the blades, and 221. a chamfer angle at the inner diameter of the blades.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. The specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. In addition, it should be noted that, for convenience of description, only a part of structures related to the present invention, not all of the structures, are shown in the drawings.