CN101782084A - Minitype axial flow fan with C spline bent blades - Google Patents

Abstract

The invention relates to a minitype axial flow fan with C spline bent blades. The minitype axial flow fan comprises a motor, a hub and C spline bent blades, wherein the C spline bent blades are arranged on the hub at intervals along the circumferential direction; the hub is connected with the motor through a rotating shaft; a bent line of each C spline bent blade consists of two C spline curves in smooth connection; a bent angle of the upper end wall of the bent blade is equal to that of the lower end wall and is between 10 and 40 degrees; the curvature of the bent blade is 1/6 to 1/3 times of a tangential value of the bent angle of the corresponding end wall; the outside diameter of the bent blade is no more than 120 mm; and the height of the bent blade is 0.3 times of the corresponding outside diameter. The minitype axial flow fan has the advantages that: by reasonably controlling the bending form of the blade, the loss of the end part of a blade path is reduced, the separation of a boundary layer of the surface of the blade is inhibited, and the pneumatic efficiency of the fan is improved so as to reduce the pneumatic noise. Through experiments, the minitype axial flow fan of the invention has low noise, small flowing loss and high efficiency and can be effectively applied to ventilation and radiation of various electronic devices.

Description

Minitype axial flow fan with C spline bent blades

Technical field

The present invention relates to a kind of minitype axial flow fan of electronic equipment dissipating heat ventilation usefulness, specifically have designated shape, specify bent angle, specify camber, specify the high C spline bent blades of leaf, the minitype axial flow fan of formation by on wheel hub, installing.

Background technique

The axial fan of impeller diameter below 120mm claims minitype axial flow fan, it is extensive use of in fields such as electronics industry, automatic technology, military technology, Aero-Space and household electric appliance, particularly in electronic equipments such as computer, minitype axial flow fan is the heat dissipation equipment of important process parts.

Current, along with improving constantly of electronic equipment performances such as computer, the working load of its core component strengthens day by day, and heating value is increasing.The heat dissipation problem of these electronic units is constantly outstanding, has become the serious bottleneck that its performance of restriction further improves.As the minitype axial flow fan of the main heat-dissipating part of these equipment, the raising of its heat dissipation potential is for operating rate and the performance that further promotes these electronic equipments provides possibility.

A main method that improves the minitype axial flow fan performance promptly is that its blade is carried out appropriate design.Blade can effectively reduce the blade-end loss of blast fan along circumferential skewing, thereby can play the effect that improves performance.But the method that forms bent blades is a lot, particularly curve form and bend angle to it performance impact clearly.

Chinese invention patent discloses a kind of " micro fan ", and its publication number is CN1360154.The bent blades molded lines of the minitype axial flow fan described in this patent is made up of two straight lines and the middle one or more circular arcs that are attached thereto, and blade is very short, and its leaf height only is 0.2-0.25 a times of corresponding blade external diameter.Though this bent blades moulding is simple, its concrete crooked molded lines remains in certain arbitrariness, and does not clearly limit the matching relationship and the concrete numerical value of bent angle and camber.Simultaneously, because the positive role of bending blade can not demonstrate fully on short blade, though therefore this have that utmost point short blade fan running noises is low, blast is big, its pneumatic efficiency can't be high, and promptly its unit power consumption amount can not obviously reduce.

It is CN2625621 that China's utility model patent discloses a kind of " axial fan impeller with forward curved vane " its publication number.The described axial-flow leaf of this model utility is a kind of curved blade shape of plunderring combination, and its bent angle is not to equate up and down, but progressively increases continuously from the blade root to the blade tip, and blade root not crooked (being that corresponding bent angle is 0 °), and the blade tip bent angle is not more than 40 °.This bent blades only defines along the bent angle of the high direction of leaf and changes, but does not specify the accurate mathematical feature of concrete crooked molded lines, so has certain blindness in its manufacturing.Simultaneously, because this bent blades there is no bending at blade root place, so it can not effectively reduce the blade-end loss at blade root place, so its aeroperformance has the space of further lifting.

The disclosed various bent blades of above-mentioned each patent, the selection that the relation of its crooked molded lines, camber and bent angle and value and bent blades leaf are high does not all quantize and is clear and definite.Have only reasonably optimizing and better, the better bent blades of performance of coupling ability construction efficient, thereby could improve the performance of whole minitype axial flow fan above-mentioned these design parameters.

Summary of the invention

The present invention is the minitype axial flow fan that a kind of C of having spline bent blades will be provided, and its purpose is to quantize the mathematical analysis formula of the crooked molded lines of bent blades in the minitype axial flow fan, and the optimization and the coupling of important design parameter (camber, bent angle, leaf height).Minitype axial flow fan operational efficiency, aerodynamic noise can be significantly increased.

Technological scheme of the present invention is: a kind of minitype axial flow fan of the C of having spline bent blades, comprise motor, wheel hub, C spline bent blades, and the C spline bent blades is along circumferentially being installed in equally spacedly on the wheel hub, and wheel hub is connected with motor by running shaft; Be characterized in: the crooked molded lines of C spline bent blades is by two smooth being formed by connecting of C spline curve, and satisfies following analytical expression:

$\left\{\begin{array}{cc}x=\frac{3\tan {\mathrm{\α}}_1+\tan {\mathrm{\α}}_2-16e}{L^2}{y}^3-\frac{7{\tan \mathrm{\α}}_1+{\tan \mathrm{\α}}_2-24e}{2L}{y}^2+y{\tan \mathrm{\α}}_1& y\∈[0,\frac{1}{2}L]\\ \begin{array}{c}x=\frac{-{\tan \mathrm{\α}}_1-3{\tan \mathrm{\α}}_2+16e}{L^2}{y}^3+\frac{{5\tan \mathrm{\α}}_1+11{\tan \mathrm{\α}}_2-72e}{2L}{y}^2+\\ (-2{\tan \mathrm{\α}}_1-3{\tan \mathrm{\α}}_2+24e)y+(-\mathrm{Le}+\frac{1}{2}L{\tan \mathrm{\α}}_1+\frac{1}{2}{L\tan \mathrm{\α}}_2)\end{array}& y\∈[\frac{1}{2}L,L]\end{array}\right.$

In the following formula: x, y: refer to the concrete mathematics coordinate figure of the crooked molded lines of bent blades on X, Y-axis respectively;

α ₁, α ₂: the bending angle that refers to bent blades root and top respectively;

E, L: refer to bent blades camber and Ye Gao respectively.

The upper end wall bent angle of bent blades equates that with the lower end wall bent angle size is 10 °～40 °; The camber of bent blades is 1/6～1/3 times of respective end walls bent angle tangent value;

The external diameter of bent blades is not more than 120mm, and its leaf height is 0.3 times of respective outer diameters; The sense of rotation of bent blades is its crooked direction.

The present invention compared with prior art has following beneficial effect:

1. the bent blades forming method among the present invention is associated blade end wall bent angle with blade camber, and the crooked molded lines of whole blade is to have the smooth C batten type curve of high-order.This forming method has overcome only to be paid attention to determining of end wall bent angle and there is random shortcoming in the concrete shape of bending blade definite in the prior art.

2. the bent blades among the present invention has rational coupling between its camber, bent angle and the leaf height, and this makes it have enough degree of crook in the end and keeps straight as far as possible in the middle part of the leaf height.This warp architecture can not only effectively reduce blade-end loss in the blade passage, strengthen the anti-stall performance of corresponding fan, improving the ability of its stable operation under low flow rate condition, and helps to improve the aeroperformance under the big flow operating mode.

3. the present invention compares with similar fan performance, have advantages such as blast is big, efficient is high, noise is low, variable working condition adaptability is strong, special all insensitive for the inclined to one side performance of operating condition under the large and small flow, overcome that conventional bent blades fan has greater efficiency but be the drawback of cost, especially be fit to the ventilation and the heat radiation of various electronic equipments to sacrifice blast.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the long-pending repeatedly line schematic representation of C spline bent blades.

Embodiment

Below in conjunction with drawings and Examples the present invention is described in detail.But present embodiment is not limited to the present invention, and every employing analog structure of the present invention and similar variation thereof all should be listed protection scope of the present invention in.

As Fig. 1, shown in 2, the minitype axial flow fan with C spline bent blades of the present invention comprises motor 1, wheel hub 2, C spline bent blades 3.

C spline bent blades 3 equally spaced being installed on the wheel hub 2, wheel hub 2 is connected with motor 1 by running shaft, and the crooked molded lines 7 of C spline bent blades 3 is by two smooth being formed by connecting of C spline curve, and satisfies following mathematical analysis relation:

$\left\{\begin{array}{cc}x=\frac{3\tan {\mathrm{\α}}_1+\tan {\mathrm{\α}}_2-16e}{L^2}{y}^3-\frac{7{\tan \mathrm{\α}}_1+{\tan \mathrm{\α}}_2-24e}{2L}{y}^2+y{\tan \mathrm{\α}}_1& y\∈[0,\frac{1}{2}L]\\ \begin{array}{c}x=\frac{-{\tan \mathrm{\α}}_1-3{\tan \mathrm{\α}}_2+16e}{L^2}{y}^3+\frac{{5\tan \mathrm{\α}}_1+11{\tan \mathrm{\α}}_2-72e}{2L}{y}^2+\\ (-2{\tan \mathrm{\α}}_1-3{\tan \mathrm{\α}}_2+24e)y+(-\mathrm{Le}+\frac{1}{2}L{\tan \mathrm{\α}}_1+\frac{1}{2}{L\tan \mathrm{\α}}_2)\end{array}& y\∈[\frac{1}{2}L,L]\end{array}\right.$

In the following formula: x, y: refer to the concrete mathematics coordinate figure of the crooked molded lines of bent blades on X, Y-axis respectively;

α ₁, α ₂: the bending angle that refers to bent blades root and top respectively;

E, L: refer to bent blades camber and Ye Gao respectively;

The upper end wall bent angle 4 of C spline bent blades 3 equates that with lower end wall bent angle 8 size is 10 °～40 °, and its camber is that camber is 1/6～1/3 times of respective end walls bent angle 4,8 tangent values; When the value of bent blades 3 cambers be respective end walls bent angle 4,8 tangent values 1/6 the time, then the value of its bent angle 4,8 should be 25 °～40 °; If the value of bent blades 3 cambers is 1/3 o'clock of respective end walls bent angle 4,8 tangent values, then the value of its bent angle 4,8 should be 10 °～30 °; If when the value of bent blades 3 cambers was 1/6～1/3 times respective end walls bent angle 4,8 tangent values (do not comprise 1/6,1/3 two kind of situation), then the value of its bent angle 4,8 should be 20 °～30 °, and bigger camber should select less bent angle, and vice versa;

The external diameter of bent blades 3 is not more than 120mm, and its leaf high 5 is 0.3 times of respective outer diameters; The sense of rotation of bent blades 3 is its crooked direction; C spline bent blades sagitta 6 is the product of leaf high 5 and camber.

When blade rotation, the flecition of blade upper and lower end parts can produce the pressure gradient of pointing to the blade middle part, this pressure gradient can make the low energy fluid that accumulates in upper and lower end parts originally converge in the main flow at blade middle part, thereby effectively reduce the blade-end loss in the blade passage, the anti-stall performance of the corresponding fan of enhancing, improved the fan aeroperformance.

Claims (4)

1. minitype axial flow fan with C spline bent blades, comprise motor (1), wheel hub (2), C spline bent blades (3), C spline bent blades (3) is along circumferentially being installed in equally spacedly on the wheel hub (2), wheel hub (2) is connected with motor (1) by running shaft, it is characterized in that: the crooked molded lines (7) of described C spline bent blades (3) is by two smooth being formed by connecting of C spline curve, and satisfies following analytical expression:

$\left\{\begin{array}{cc}x=\frac{3\tan {\mathrm{\α}}_1+\tan {\mathrm{\α}}_2-16e}{L^2}{y}^3-\frac{7{\tan \mathrm{\α}}_1+\tan {\mathrm{\α}}_2-24e}{2L}{y}^2+y\tan {\mathrm{\α}}_1& y\∈[0,\frac{1}{2}L]\\ x=\frac{-{\tan \mathrm{\α}}_1-3{\tan \mathrm{\α}}_2+16e}{L^2}{y}^3+\frac{5\tan {\mathrm{\α}}_1+11\tan {\mathrm{\α}}_2-72e}{2L}{y}^2+& \\ (-2\tan {\mathrm{\α}}_1-3\tan {\mathrm{\α}}_2+24e)y+(-\mathrm{Le}+\frac{1}{2}L{\tan \mathrm{\α}}_1+\frac{1}{2}L{\tan \mathrm{\α}}_2)& y\∈[\frac{1}{2}L,L]\end{array}\right.$

In the formula: x, y: be meant the concrete mathematics coordinate figure of the crooked molded lines of bent blades on X, Y-axis respectively;

α ₁, α ₂: the bending angle that is meant bent blades root and top respectively;

E, L: be meant bent blades camber and Ye Gao respectively.

2. the minitype axial flow fan with C spline bent blades according to claim 1 is characterized in that: the upper end wall bent angle (4) of described bent blades (3) equates that with lower end wall bent angle (8) size is 10 °～40 °; The camber of bent blades (3) is 1/6～1/3 times of respective end walls bent angle tangent value.

3. the minitype axial flow fan with C spline bent blades according to claim 1 and 2 is characterized in that: the external diameter of described bent blades (3) is not more than 120mm, and its leaf height (5) is 0.3 times of respective outer diameters.

4. the minitype axial flow fan with C spline bent blades according to claim 1 and 2 is characterized in that: the sense of rotation of described bent blades (3) is its crooked direction.

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