Fan cowl for the reduction of oscillations of an impeller

Abstract

A fan cowl (1) for receiving at least one fan (2) which is spaced apart relative to a cooler (4), having a fan frame (6) which can be attached to the cooler (4) with at least one cutout (8) for feeding air to an impeller (10) of the fan (2), the cutout (8) having a centered motor receptacle (12) for receiving a fan motor (14) which can be driven electrically, and the cutout (8) being surrounded on the circumferential side by a fan shroud (16). It is proposed that the fan shroud (16) has at least one opening (20) for setting an air pressure distribution which can be generated by way of the fan. A fan arrangement (22), having a fan cowl (1) of this type.

Claims

1. A fan cowl (1) for receiving at least one fan (2), the fan cowl (1) having a fan frame (6) with at least one cutout (8) for feeding air to an impeller (10) of the fan (2), the cutout (8) having a centered motor receptacle (12) for receiving a fan motor (14) which is configured to be driven electrically, and the cutout (8) being surrounded on the circumferential side by a fan shroud (16), characterized in that the fan shroud (16) has at least one opening (20) for setting an air pressure distribution which is configured to be generated by way of the fan, wherein the fan shroud (16) has a shroud bottom and at least one shroud wall which merge into one another in the form of a curve or at a right angle, and the at least one opening (20) is made in the shroud bottom and/or in the at least one shroud wall of the fan shroud (16), wherein the at least one opening (20) is oriented in the fan shroud (16) such that air passes through the at least one opening in the fan shroud (16), and thereby through the fan shroud (16), in an axial direction, wherein the shroud wall defines an outermost perimeter, and wherein the at least one opening (20) is at least partially disposed radially within the outermost perimeter.

2. The fan cowl according to claim 1, the fan shroud (16) configured to cover the impeller (10) of the fan (2) at least in regions.

3. The fan cowl according to claim 1, the fan shroud (16) having a V-shaped, L-shaped or U-shaped cross section which is open in a direction of the fan (2).

4. The fan cowl according to claim 1, the at least one opening (20) being of rectangular, square, cuboid, oval or circular configuration.

5. The fan cowl according to claim 1, the fan shroud (16) having a plurality of openings (20), the openings (20) being distributed over a circumference of the fan shroud (16).

6. The fan cowl according to claim 1, the fan shroud (16) having a plurality of openings (20), the openings (20) being distributed along a circumferential section of the fan shroud (16).

7. The fan cowl according to claim 6, the openings (20) being distributed along a circumferential half of the fan shroud (16).

8. A fan arrangement (22), having a fan cowl (1) according to claim 1 and having at least one fan (2) which is inserted into the fan cowl (1) with a fan motor (14) and with an impeller (10) which is configured to be driven by way of the fan motor (14).

9. The fan arrangement (22) according to claim 8, wherein the at least one opening (20) is intermittently covered by the impeller (10) of the fan (2) during rotation of the impeller (10).

10. A fan arrangement (22), having a fan cowl (1) according to claim 1 and having an impeller (10) which is inserted into the fan cowl (1), wherein the at least one opening (20) is positioned such that the at least one opening (20) is intermittently covered in the axial direction by the impeller (10) during rotation of the impeller (10).

11. The fan cowl according to claim 1, the fan shroud (16) having a plurality of openings (20), the openings (20) being distributed along only a first circumferential half of the fan shroud (16) and not being distributed along a second circumferential half of the fan shroud (16).

12. The fan cowl according to claim 1, wherein the at least one opening (20) is radially adjacent the shroud wall.

13. The fan cowl according to claim 1, wherein the at least one opening (20) is in the shroud bottom and is radially adjacent the shroud wall.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following text, preferred exemplary embodiments of the invention will be described in greater detail on the basis of greatly simplified diagrammatic illustrations. In the drawing:

(2) FIG. 1 shows a diagrammatic illustration of a fan cowl in accordance with one embodiment,

(3) FIG. 2 shows a detailed view of a fan arrangement with the fan cowl from FIG. 1,

(4) FIG. 3 shows a diagram for illustrating noise levels of a fan arrangement with the fan cowl which is shown in FIG. 1, with measured data which are determined in a test bench experiment,

(5) FIG. 4 shows a diagram for illustrating noise levels of a fan arrangement with the fan cowl which is shown in FIG. 1, with measured data which are determined in a surrounding area of the vehicle, and

(6) FIG. 5 shows a diagram for illustrating an operational performance of a fan arrangement with a fan cowl from FIG. 1.

DETAILED DESCRIPTION

(7) FIG. 1 shows a diagrammatic illustration of a fan cowl 1 in accordance with one embodiment. The fan cowl 1 serves for arranging at least one fan 2 relative to a cooler 4, which are shown in FIG. 2.

(8) The fan cowl 1 has a fan frame 6 which can be attached to the cooler 4 with at least one cutout 8 for feeding air to an impeller 10 (shown in FIG. 2) of the fan 2.

(9) The fan frame 6 is of substantially rectangular form and surrounds the cutout 8. The fan frame 6 can have a form and extent in accordance with a form and extent of the cooler 4.

(10) The fan cowl 1 can be fastened to the cooler 4 or directly to a surround of the cooler 4 at fastening points 7 which extend from the fan frame 6. For example, the fan cowl 1 can be fixed by way of screws at the fastening points 7.

(11) The cutout 8 has a centered motor receptacle 12 for receiving a fan motor 14 which can be driven electrically.

(12) The cutout 8 is surrounded on the circumferential side by a fan shroud 16. The fan shroud 16 is of annular configuration and delimits the cutout 8 in the radial direction R along the entire circumference of the cutout 8.

(13) The motor receptacle 12 is arranged in the cutout 8 in a centered manner via struts 18. The struts 18 extend from the fan frame 6 or from the fan shroud 16.

(14) Openings 20 are made in the fan shroud 16, which openings 20 extend through the fan cowl 1 or the fan shroud 16 parallel to the cutout 8.

(15) In the exemplary embodiment which is shown, four openings 20 are configured on a lower circumferential half (in the direction of gravity S) of the fan shroud 16, in order to act on an air pressure distribution which can be generated by way of the fan 2. The lower circumferential half of the fan shroud 16 is illustrated in detail in FIG. 2.

(16) The openings 20 can be, for example, round, oval, square, rectangular and the like in shape. For example, the openings 20 can have a circumferential width or dimension in an order of magnitude of from 0.1 to 20 cm inclusive. Here, one opening 20 or a plurality of openings 20 can be made in the fan shroud 16.

(17) The openings 20 establish an air-conducting connection between the two flat sides of the fan cowl 1, and make a local increase of the air volume which is available to the fan 2 possible.

(18) FIG. 2 shows a detailed view of a fan arrangement 22 with the fan cowl 1 from FIG. 1. The fan arrangement 22 has a fan cowl 1, a fan motor 14 which is fastened in the motor receptacle 12, and an impeller 10 which can be driven by way of the fan motor 14.

(19) The impeller 10 has a plurality of blades which suck in the air via the cutout 8 during operation of the fan motor 14 and can accelerate in the direction of the cooler 4. In the exemplary embodiment which is shown, the fan 2 with the fan motor 14 and the impeller 10 is situated behind the fan cowl 1 and in front of the cooler 4.

(20) In the exemplary embodiment which is shown, four openings 20 are made in the fan shroud 16. The openings 20 are positioned in a mirror-symmetrical manner along a vertically running symmetry axis V.

(21) Depending on the configuration, for example, two, six, eight or more openings 20 can also be arranged along a circumferential half or along a circumferential section of the fan shroud 16.

(22) The fan shroud 16 has openings 10 which are arranged, for example, only on the lower circumferential half, because a cooler or radiator 4 is covered by way of the fan 2 only in regions. On a lower section 5, the cooler 4 can have an offset with respect to an air conditioning condenser or intercooler which is arranged in parallel. There is therefore a greater axial spacing between the impeller 10 and a surface to be cooled in the region of the lower section 5, which can cause increased volume and roughness.

(23) FIG. 3 shows a diagram for illustrating noise levels of a fan arrangement 22. The fan arrangement 22 has a fan cowl 1 which is shown in FIG. 1. The measured data which can be seen in the diagram were determined in a test bench experiment. The diagram shows a noise level in dBA and a set power output of the fan motor 14 in percent. The diagram shows a comparison between a regular fan cowl and a fan cowl 1 with openings 20 which are made in the fan shroud 16.

(24) Two measuring sequences 24, 26 are shown which illustrate operating noise 24 of the fan motor 14 and operating noise 26 of the impeller 10, in particular operating noise 26 which is caused by way of the blade pass frequency, in the case of a different power output of the fan motor 14.

(25) FIG. 4 shows a diagram for illustrating noise levels of a fan arrangement 22 with the fan cowl 1 which is shown in FIG. 1. The measured data were determined in a vehicle surrounding area. Here, in an analogous manner with respect to FIG. 3, operating noise 24 of the fan motor 14 and operating noise 26 of the impeller 10 are shown.

(26) In contrast to the diagram which is shown in FIG. 3, the measured data were measured in a field test in a surrounding area of the vehicle and in an installed state of the fan arrangement 22.

(27) As can be seen in FIG. 3 and FIG. 4, a considerable reduction of the operating noise 26 of the impeller 10 results by way of the openings 20, in particular in the case of relatively high power outputs of the fan motor 14.

(28) FIG. 5 shows a diagram for illustrating an operational performance of a fan arrangement 22 with a fan cowl 1 from FIG. 1. Here, a static pressure p is shown in mmAq, and the air mass throughput A is shown in cubic meters per hour.

(29) It can be seen from the diagram that the use of the openings 20 has substantially no effects on the air mass throughput A or the generated pressure p of the fan 2.