EP3298284A1

EP3298284A1 - Flat flow-conducting grille

Info

Publication number: EP3298284A1
Application number: EP16723750.2A
Authority: EP
Inventors: Zhang BINYUAN; Christian Haag; Carsten HÜBNER; Björn Sudler; Manuel Vogel
Original assignee: Ebm Papst Mulfingen GmbH and Co KG
Current assignee: Ebm Papst Mulfingen GmbH and Co KG
Priority date: 2015-05-20
Filing date: 2016-05-19
Publication date: 2018-03-28
Anticipated expiration: 2036-05-19
Also published as: EP3298284B1; US10590954B2; WO2016184970A1; US20180298916A1; CN204783851U; DE102015107907A1

Abstract

The invention relates to a flow-conducting grille designed as a pre-conducting grille for arranging on an suction region of a fan, wherein the flow-conducting grille has a grille web structure about an axial center line, which grille web structure comprises radial webs spaced apart in the circumferential direction and coaxial circumferential webs spaced apart in the radial direction and an outer ring, wherein an inflow side of the flow-conducting grille extends flatly and parallel to a radial plane of the flow-conducting grille.

Description

Eben Strömungsleitgitter

Description:

The invention relates to a Strömungsleitgitter formed as Vorleitgitter for arrangement at the intake of a fan,

Vorleitgitter are known from the prior art in various designs and variants, in particular in a curved shape or as a spherical cap. Corresponding disclosures can be found, for example, in the patent applications DE 10 2014 116 047 A, EP 2 778 432 A1 or DE 1 052 624 B. The derived from the applicant and known from the prior art Strömungsleitgitter or flow rectifiers work very well in practice, but require due to their curvature in the axial direction of a certain space in order to function optimally. In narrow installation conditions, the curved shape is therefore not always advantageous.

The invention is therefore based on the object to provide a Strömungsleitgitter that compared to the known from the prior art solutions in the axial direction has a smaller footprint, while maintaining the performance at least and the noise is at least not increased. It is another object of the invention to develop a fan with a corresponding Strömungsleitgitter to a compact unit.

These objects are achieved by the combination of features of the respective independent claims. According to the invention a Strömungsleitgitter is designed as Vorleitgitter for arrangement at a suction of a fan proposed, which has an axial center line a lattice web structure, the circumferentially spaced radial webs and radially spaced coaxial peripheral webs and an outer ring comprises. In the case of the flow-guiding grille, the inflow side extends flat and parallel to one of its radial planes. The flat, planar extension allows utilization of the minimization of turbulence in the intake on the inflow side of the Strömungsleitgitters even in tight installation conditions.

To further reduce the required axial space is provided in an embodiment of the invention that the Strömungsleitgitter is flat and the ratio of its maximum outer diameter D ₃ (inside width) to its axial total height H in a range of 6 - 25, preferably 10 - 15 is fixed. The flat geometry in the mentioned value range leads to low construction heights of the flow guide on the fan and benefits takes a compact overall structure.

In an advantageous embodiment, it is provided that in a central region of the Strömungsleitgitters around its axial center line a central opening is formed with an inflow-side central diameter Di, wherein the ratio of the central diameter Di against a maximum outer diameter D _{3 of} the Strömungsleitgitters (inside diameter) in a range of 1 , 5-6.0, preferably 2.0-2.5. The central opening is bounded radially on the outside by the first peripheral ridge and offers the possibility of arranging components of the connected fan in the region of the flow guide, so that, for example, the rotor bell extends axially into the flow guide and thus minimizes the axial assembly height of the fan together with the flow guide ,

It is further provided in a development of the invention that seen in the radial outward direction first coaxial circumferential ridge has an extension from the inflow side to an outflow side, which is inclined α relative to the axial center line by an angle radially outward. The second coaxial circumferential ridge viewed in the radial outward direction, in an advantageous embodiment, has an extension from the inflow side to an outflow side, which is inclined radially inwards relative to the axial center line by an angle β.

The extensions of the first and second coaxial circumferential webs viewed in the radial outward direction form in an imaginary extension of their axial end points at a distance L from the inflow side an intersection which determines an intersection point diameter D ₄ radially spaced from the axial center line, ie the circumferential webs are aligned with each other so that imaginary extensions of a connecting line of their respective end points intersect in a plane axially spaced from the Strömungsleitgitter. The mutually facing circumferential webs generate a flow which is advantageous for the fan power and noise generation in a forward direction. certain radial distance to axial centerline.

In a likewise favorable development of the invention, the Strömungsleitgitter is characterized in that a ratio of the intersection diameter D against an outflow-side outer diameter D _{3 of} the Strömungsleitgitters is set in a range of 0.01 - 0.8. As a further advantageous ratio of the invention, the intersection diameter D ₄ with respect to the axial distance of the intersection point L in a range of 0 - 1, 6 set. In addition, the ratio of the axial height H of the Strömungsleitgitters compared to the axial distance of the intersection point L in a range of 0.01 - 0.5 set according to the invention in one embodiment. The conditions of the invention ensure a supply and flow through the air sucked by the fan to and through the planar Strömungsleitgitter at a relative to curved versions not increased noise. In the Strömungsleitgitter invention is further provided in a favorable embodiment, that seen in the radial direction of the first and second coaxial circumferential webs each have an axial extent H1, H2 parallel to the axial center line whose relation to the axial height H to H1 <H2 <H is fixed , The axial extent of the radial webs increases over the respective radial length of the first peripheral ridge up to the outer ring.

The first and second coaxial circumferential webs, seen in the radial direction, are advantageously curved in a convex manner in the direction of the axial center line. The shape of the circumferential webs has a direct positive effect on the flow in the axial direction.

Furthermore, it is favorable in terms of flow, if the Strömungsleitgitter has a plurality of radial webs, which are each spaced in a circumferential angle δ of 0 - 20 °, preferably 15 °. The number of radial webs is an influencing factor both on the performance of the Strömungsleitgitters and the noise generated by its use.

In an advantageous variant of the invention, the grating structure of the Strömungsleitgitters on a geometry in which in an axial plan view of the inflow side between each adjacent radial webs and between the radially first and second coaxial circumferential webs meshes with a first diagonal extension Li and between each adjacent Radial webs and formed between the second coaxial circumferential ridge seen in the radial direction and the outer ring each mesh grid with a second diagonal extent L ₂ , wherein a ratio of the diagonal extents Li <L _{2 is} fixed.

With regard to the outflow side, it is advantageous according to the invention that in an axial plan view between respectively adjacent radial webs and between the first and second coaxial circumferential webs viewed in the radial direction, grid meshes with a first diagonal extension (L ₃ ) and between respectively adjacent radial webs and between them in the radial direction seen second coaxial circumferential ridge and the outer ring each grid meshes are formed with a second diagonal extent (L), wherein a ratio of the diagonal extents L ₃ <L _{4 is} fixed. The geometry of the grid mesh according to the invention allows increased flow in the radial outer area.

The invention also encompasses a ventilator having a drive unit and a flow guide grid described above, which is characterized in that the drive unit extends at least in sections in the axial direction into an area of the flow guide grid in order to ensure the compact construction.

In a development, it is additionally provided that the ratio of the radial distance SPm between the radial outer edge of the drive unit and the outflow-side central diameter D _{2 of} the central opening and the inflow-side central diameter Di is smaller or equal to a value 0.15 is set.

Other advantageous developments of the invention are characterized in the subclaims or will be explained in more detail below together with the description of the preferred embodiment of the invention with reference to the figures. Show it:

Fig. 1 is a plan view of the inflow side of a Strömungsleitgitters;

Fig. 2 is a side sectional view of one half of the Strömungsleitgitters of Fig. 1; 3 is a plan view of the inflow side of a Strömungsleitgitters.

4 is a plan view of the downstream side of a Strömungsleitgitters.

5 shows an installation situation of the Strömungsleitgitters on a fan in a side view.

6 shows a characteristic comparison of the Strömungsleitgitters invention.

In Fig. 1 is a plan view of the inflow side of a Strömungsleitgitters 1 is shown. The Strömungsleitgitter 1 is formed as Vorleitgitter for arrangement at the intake of a fan 50, as shown by way of example in Fig. 5. To an axial center line ML, the Strömungsleitgitter 1 a grid web structure with circumferentially spaced radial webs 2 and spaced radially and coaxially arranged circumferential webs 3, 4 and a the outer edge final outer ring 5 on. In the central area about the axial center line ML, a central opening 6 delimited by the innermost radial web 3 is provided. 2 is a side sectional view of a half of the Strömungsleitgitters 1 of FIG. 1. The lying in Fig. 2 above the inflow side of the Ström ungsleitg Itters 1 is planar flat and extends parallel to its radial plane, wherein all elements of the Strömungsleitgitters 1, ie the outer ring 5, the radial webs 2 and the peripheral webs 3, 4 end in a radial plane of the inflow side. The outer ring 5 forms the radial and axial end, wherein the transition is determined by a predetermined rounding R of R = 10mm in the embodiment. The radial webs 2 extend on the inflow side over a diameter D ₆ , on the downstream side almost to the outer ring 5, which is determined in this area by the diameter D ₃ . The peripheral webs 3, 4 extend in the radial direction

on the inflow side over the diameters Di, D ₅ and on the outflow side over the diameters D ₂ , D ₇ . In the axial direction, the circumferential webs 3, 4 are curved convexly in the direction of the center line from the inflow side in the direction of the outflow side, wherein the radially inner circumferential ridge 3 has a curvature in the direction of the outflow side and the circumferential ridge 4 has a curvature in the direction of the inflow side. The circumferential ridge 3 also extends from the inflow side to the outflow side with respect to the axial center line at an angle of a = 18 ° inclined radially outward. The further radially outer circumferential ridge 4 extends from the inflow side to the downstream side with respect to the axial center line at an angle of ß = -12 ° radially inwardly inclined, so that the circumferential webs 3, 4 in an imaginary extension at a distance L to the inflow side Form intersection 7. The intersection 7 is radially spaced from the axial center line ML and extends circumferentially at the intersection diameter D ₄ . The axial height Hi of the innermost circumferential ridge 3 is smaller than the axial height H _{2 of} the second circumferential ridge 4, which in turn is smaller than the total axial height H of the Strömungsleitgitters 1, which is determined by the outer ring 5 in the embodiment shown. The radial webs 2 are formed such that increases their axial height, starting from the innermost circumferential ridge 3 in the direction radially outward to the outer ring 5. In the Strömungsleitgitter 1 shown in Figures 1 and 2, the ratio of the maximum outer diameter D ₃ to the axial height H takes a value of 12, 14 a. The ratio of the inflow-side central diameter Di to the maximum outer diameter D ₃ is 2, 19. The ratio of the intersection diameter D to the outflow-side outer diameter D ₃ is set to a value of 0.74. The ratio of the intersection diameter D ₄ to the distance L to

Inflow side takes a value of 1.55. The ratio of the axial height H to the distance L to the inflow side is 0.47. Figures 3 and 4 each show a plan view of the inflow side and outflow side of the Strömungsleitgitters 1 of Figures 1 - 2. The radial webs 2 are each spaced at a circumferential angle 5 = 15 °, so that 24 radial webs 2 are provided in the illustrated embodiment. The lattice meshes determined by the radial webs 2 and peripheral webs 3, 4 each have a diagonal extension which is set so that the grid meshes lying further radially outwards are larger both on the inflow side and on the outflow side. For this reason, the ratio L ₁ <L ₂ applies on the inflow side, and the ratio L ₃ <L _{4 on the} outflow side.

FIG. 5 shows an installation situation of the flow guide grid 1 from FIG. 1 on a ventilator 50 in a side view. The fan 50 includes a motor having a rotor bell 51 with a diameter DM. In the axial direction, the rotor bell 51 extends into the central opening 6 of the Strömungsleitgitters 1, radially, however, a radial distance SPm between the radial outer edge of the rotor bell 51 and the

provided on the outlet-side center diameter D _{2 of} the central opening (corresponding to the downstream diameter of the inner circumferential ridge 3). Its ratio to the inflow-side center diameter Di (which corresponds to the inflow-side diameter of the inner peripheral ridge 3) is set to a value of 0.13. Fig. 6 shows a characteristic comparison, each using a

Zuströmbox, the Strömungsleitgitters invention 1, wherein the characteristics of the Strömungsleitgitters of Fig. 1 - 4 are provided with the reference numeral 200. On the other hand, characteristic curves without Strömungsleitgitter with the reference numeral 100 and characteristic curves with a known from the prior art Strömungsleitgitter designated by the reference numeral 300. The positive effect of the inventive Strömungsleitgitters 1 with respect to a noise reduction in dBA shows especially at delivery figures (Phi) of 0.04 - 0.1. The total pressure difference is particularly favorable for high delivery figures.

The invention is not limited in its execution to the above-mentioned preferred embodiments. Rather, a number of variants is conceivable, which makes use of the illustrated solution even with fundamentally different types of use. For example, the number of peripheral webs is not limited to two, but any number of additional circumferential webs can be provided.

Claims

claims

Strömungsleitgitter formed as Vorleitgitter for placement on a suction of a fan, wherein it has around an axial center line (ML) a lattice web structure, the circumferentially spaced radial webs (2) and radially spaced coaxial Umfang fangs (3, 4) and an outer ring (5), wherein an inflow side of the Strömungsleitgitters (1) extends flat and parallel to a radial plane of the Strömungsleitgitters (1).

Strömungsleitgitter according to claim 1, characterized in that it is flat and a ratio D ₃ / H of its maximum outer diameter (D ₃ ) to the axial height (H) in a range of 6-25 is fixed.

Strömungsleitgitter according to claim 1 or 2, characterized in that it is formed in a central region about its axial center line with a central opening (6) with a inflow-side central diameter (Di), wherein its relation to a maximum outer diameter (D ₃ ) of the Strömungsleitgitters (1 ) is set in a range of D3 / D1 = 1.5-6.0.

Strömungsleitgitter according to at least one of the preceding claims, characterized in that viewed in the radial direction of the first coaxial circumferential ridge has an extension from the inflow side to a downstream side, which is inclined relative to the axial center line by an angle (a) radially outward.

Strömungsleitgitter according to at least one of the preceding claims, characterized in that seen in the radial direction second coaxial circumferential ridge has an extension from the inflow side to an outflow side, which is inclined relative to the axial center line by an angle (ß) radially inward.

6. Strömungsleitgitter according to claims 4 and 5, characterized in that the extensions of the viewed in the radial direction of the first and second coaxial circumferential webs (3, 4) in an imaginary extension at a distance (L) from the inflow side a cut point (7) form, which determines a relation to the axial center line (ML) radially spaced intersection diameter (D ₄ ).

7. Strömungsleitgitter according to the preceding claim, characterized in that a ratio D ₄ / D _{3 of} the intersection diameter (D) against a downstream-side outer diameter (D ₃ ) of the Strömungsleitgitters (1) in a range of 0.01 - 0.8 is fixed ,

8. Strömungsleitgitter according to one of claims 6 to 7, characterized in that a ratio D ₄ / L of the intersection diameter (D) over the distance (L) between the intersection (7) and the inflow side in a range of 0 - 1, 6 is fixed.

9. Strömungsleitgitter according to at least one of the preceding claims 6 to 8, characterized in that a ratio H / L of its axial height (H) of Strömungsleitgitters (1) relative to the distance (L) between the intersection (7) and the inflow side in one Range is set from 0.01 to 0.5.

10. Strömungsleitgitter according to the preceding claim, characterized in that seen in the radial direction of the first and second coaxial circumferential webs (3, 4) each have an axial extension (Η-ι, H ₂ ) parallel to the axial center line (ML), the ratio of their the axial height (H) of the Strömungsleitgitters (1) to Hi <H ₂ <H is set.

1 1. Strömungsleitgitter according to at least one of the preceding claims, characterized in that seen in the radial direction of the first and second coaxial circumferential ridge (3, 4) convex in the direction of the axial center line (ML) are formed curved.

12. Strömungsleitgitter according to at least one of the preceding claims, characterized in that the radial webs (2) each at a circumferential angle (δ) of <20 ° are spaced apart.

13. Strömungsleitgitter according to at least one of the preceding claims, character- ized in that in an axial plan view of the

Inflow side between each adjacent radial webs (2) and between the first and second coaxial circumferential webs seen in the radial direction (3, 4) grid meshes with a first diagonal extension (Li) and between each adjacent radial webs (2) and between the second coaxial seen in the radial direction Perimeter web (4) and the outer ring (5) each grid meshes are formed with a second diagonal extent (L ₂ ), wherein a length ratio Li <L _{2 is} fixed.

14. Strömungsleitgitter according to at least one of the preceding claims, characterized in that in an axial plan view of the

Outflow side between each adjacent radial webs (2) and between the first and second coaxial circumferential webs seen in the radial direction (3, 4) grid meshes with a first diagonal extension (L ₃ ) and between each adjacent radial webs (2) and between the second seen in the radial direction Coaxial circumferential web (4) and the outer ring (5) each grid meshes are formed with a second diagonal extent (L ₄ ), wherein an aspect ratio L ₃ <L _{4 is} fixed.

15. Fan with a drive unit and a Strömungsleitgitter according to one of the preceding claims, characterized in that the

Drive unit at least partially in the axial direction in a region of the Strömungsleitgitters (1) extends into it and a ratio of a radial distance (SPm) between a radial outer edge of the drive unit and a downstream-side central diameter (D ₂ ) the central opening (6) and the inflow-side center diameter (Di) is set to a value SPm / Di 0.15.

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