DE102020113962A1 - Inlet nozzle for a turbo machine and turbo machine - Google Patents

Abstract

The invention relates to an inlet nozzle (6) for a turbo machine (1), in particular for a radial fan (2) or a diagonal fan, wherein the inlet nozzle (6) surrounds an inlet duct (8) in an annular manner and the inlet nozzle (6) with one of the inlet ducts (8) delimiting surface (101), viewed in radial cross-sections, is convex to a longitudinal center axis (L6) of the inlet nozzle (6) running in an inflow direction (x) and is designed to be rotationally symmetrical. Here, the surface (101) of the inlet nozzle (6) has geometrical irregularities (102a, 102b, 102c) running radially, the rotational symmetry of the surface (101) being canceled by the geometrical irregularities (102a, 102b, 102c).

Description

The invention relates to an inlet nozzle for a turbo machine according to the preamble of claim 1 and a turbo machine according to the preamble of claim 9.

From the applicant's product brochure “RadiPac EC radial fans” with the identifier “37898-7-8811 2015-09 WO-1 '”, a flow machine designed as a radial fan is known, which comprises an inlet nozzle, the inlet nozzle surrounding an inlet channel in an annular manner , the inlet nozzle having a surface delimiting the inlet channel, viewed in radial cross-sections, being essentially convex to a longitudinal center axis of the inlet nozzle running in an inflow direction and being designed to be rotationally symmetrical, the turbomachine further comprising a fan wheel and an electric motor, the fan wheel being driven by the electric motor and wherein the fan wheel is received in the fluid space. In the further development of an inlet nozzle of such a turbo machine or in the further development of such a turbo machine, it was found that undesired noise peaks occur when starting up.

The invention is based on the object of developing an inlet nozzle for a turbomachine or a turbomachine, by means of which or in which it is avoided that noise peaks occur when running up.

Based on the features of the preamble of claims 1 and 9, this object is achieved by the characterizing features of claims 1 and 9, respectively. Advantageous and expedient developments are specified in the respective subclaims.

The inlet nozzle according to the invention for a turbomachine, in particular for a radial fan or a diagonal fan, surrounds an inlet channel in a ring shape, the inlet nozzle with a surface delimiting the inlet channel, viewed in radial cross-sections, being convex to a longitudinal center axis of the inlet nozzle running in an inflow direction and being designed to be rotationally symmetrical, in this case if the surface of the inlet nozzle has geometrical irregularities running around it radially and the rotational symmetry of the surface is canceled by the geometrical irregularities. Measurements on an inlet nozzle of this type have shown that such a design of the inlet nozzle prevents noise peaks over the entire speed range that is run through when starting up. Thus, the invention makes it possible to avoid the occurrence of noise peaks by a single measure for a wide variety of speeds.

It is also provided that the irregularities are designed as elevations and / or depressions and that these are arranged equidistant from the longitudinal center axis. Such an arrangement allows the irregularities to be produced in a simple manner in terms of production technology.

Provision is also made for the irregularities to be arranged symmetrically, namely regularly distributed, or asymmetrically, namely irregularly distributed, relative to the longitudinal center axis. This allows the inlet nozzle to be tailored to special requirements if necessary.

Furthermore, it is provided that the elevations are formed by deformations of the inlet nozzle or by attachments and that these are in particular formed in the shape of spherical segments. Deformations can be easily produced in terms of production technology and without additional material expenditure. Attachments allow the formation of complex geometries and can also be retrofitted.

Provision is also made for the depressions to be formed by deformations in the form of dents or by bores and for the depressions, in particular, to be designed in the shape of hollow spherical segments. Such deformations of the inlet nozzle can be carried out with simple tools and thus inexpensively.

Furthermore, it is provided that the irregularities are geometrically designed and geometrically distributed in such a way that a boundary layer of an air flow which flows through the inlet nozzle is influenced and that in particular the formation of a Kärmänsche vortex street at a rear edge of the inlet nozzle is at least hindered and in particular prevented. This reliably prevents certain resonance frequencies from being excited by Käränsche vortex streets. In this way, noise peaks caused by resonance frequencies are reliably avoided.

It is also provided that the longitudinal axes of the inlet nozzle extending in the direction of the elevations or the depressions are each at angles α1 until α3 between 20 ° and 70 ° and preferably between 30 ° and 60 ° and that preferably the longitudinal axes of all elevations or depressions cut the longitudinal center axis of the inlet nozzle at the same angles α1 until α3 cut. With such an alignment of the elevations and / or depressions, the measurements have shown particularly good avoidance of noise peaks.

Finally, it is provided that the inlet nozzle is designed with at least 15, preferably with at least 25 and particularly preferably with at least 35 irregularities, which are in particular designed as depressions and which are in particular arranged regularly. With such a number of elevations and / or depressions, measurements have shown particularly good avoidance of noise peaks.

The turbomachine according to the invention, which is designed in particular as a radial fan, comprises a fan wheel, an electric motor and a housing, the fan wheel being driven by the electric motor, the housing comprising an inlet nozzle and a fluid space opening towards the inlet nozzle, the fan wheel in the Fluid space is received and wherein the inlet nozzle is designed according to at least one of claims 1 to 8. In the case of such a turbo machine, it was determined by measurements that such a design of the inlet nozzle avoids noise peaks over the entire speed range, which is run through when starting up. Thus, the invention makes it possible to avoid the occurrence of noise peaks on such turbomachines by a single measure for a wide variety of speeds.

Finally, it is provided in the turbo engine that the inlet nozzle opens into the fan space of the chassis of the turbo engine in such a way that the inlet nozzle is received without contact in an inflow opening of the fan wheel, the inlet nozzle being connected to the front plate of the chassis and the fan wheel via the electric motor is connected to the flange plate of the motor mount of the chassis. As a result, the fan wheel is supplied with air directly from the inlet nozzle, without the need for additional components.

In the context of the invention, a run-up is understood to mean an increase in a speed of the electric motor driving the fan wheel from the standstill of the electric motor up to a target speed. In this case, the increase in the speed per unit of time takes place in particular on a curve predetermined by a motor control device.

Further details of the invention are described in the drawing with the aid of schematically illustrated exemplary embodiments.

• 1: eine erste perspektivische Ansicht einer ersten Ausführungsvariante einer erfindungsgemäßen Strömungsmaschine, welcher als Radialventilator ausgebildet ist;
• 2: eine zweite perspektivische Ansicht der aus der 1 bekannten Strömungsmaschine;
• 3: eine geschnittene Seitenansicht der aus den 1 und 2 bekannten Strömungsmaschine;
• 4a: eine erfindungsgemäße Einlassdüse der aus den 1 bis 3 bekannten Strömungsmaschine in Frontansicht, wobei die Einlassdüse in der 1 nur schematisch gezeigt und erst ab der 4a detailliert dargestellt ist;
• 4b: einen Schnitt durch die in der 4a gezeigte Einlassdüse entsprechend der Schnittlinie IVb-IVb;
• 4c: eine perspektivische Ansicht der in der 4a gezeigten Einlassdüse und
• 4d: einen Schnitt durch die in der 4c gezeigte Einlassdüse entsprechend der in der 4c gezeigten Schnittlinie IVd-IVd.

Here shows:

• 1 : a first perspective view of a first variant embodiment of a turbomachine according to the invention, which is designed as a radial fan;
• 2 FIG. 12 is a second perspective view of FIG 1 well-known turbo machine;
• 3 : a sectional side view of the from the 1 and 2 well-known turbo machine;
• 4a : an inlet nozzle according to the invention from the 1 until 3 known turbomachine in front view, the inlet nozzle in the 1 only shown schematically and only from the 4a is shown in detail;
• 4b : a cut through the in the 4a Inlet nozzle shown according to section line IVb-IVb;
• 4c FIG. 11 is a perspective view of the FIG 4a inlet nozzle shown and
• 4d : a cut through the in the 4c The inlet nozzle shown corresponds to the one in FIG 4c Section line IVd-IVd shown.

In the 1 and 2 is a fluid flow machine according to the invention 1 each shown in a perspective view. the 3 shows a sectional side view through this turbomachine 1 . The turbo machine 1 is designed as a centrifugal fan 2 educated.

The turbo machine 1 includes a fan wheel 3 , an electric motor 4th and a case 5 . The case 5 includes an inlet nozzle 6th and one towards the inlet nozzle 6th opening fluid space 7th , the inlet nozzle 6th an inlet port 8th surrounds annularly. The inlet nozzle 6th is in the 4a shown in front view. Here is the inlet nozzle 6th in the 1 only shown schematically and only in the 4a until 4d shown in detail. In the 4b is the inlet nozzle 6th in a section according to the section line IVb-IVb (see 4a) shown. In the 4c is the inlet nozzle 6th shown in a perspective view. In the 4d is a section of the inlet nozzle 6th finally in perspective in a section corresponding to the section line IVd-IVd (see 4c ) shown.

The housing also includes 5 a front panel 9 and a motor mount 11 , this being a chassis 10 form. Here the engine mount includes 11 four arms 11a until 11d and a flange plate 11e , with the four arms 11a until 11d with the front panel 9 screwed and with the engine mount 11 are connected. Here is the inlet nozzle 6th in an annular opening 9a the front panel 9 recorded and screwed to this. The flange plate 11e lies the front panel 9 opposite to. The electric motor 4th is on the flange plate 11e of the engine mount 11 flanged and in one through the flange plate 11e of the chassis 10 and the fan wheel 3 formed engine compartment 10a recorded. One between the faceplate 9 and the electric motor 4th trained Fan room 10b takes the fan wheel 3 and forms the fluid space 7th which is to the inlet nozzle 6th opens.

The inlet nozzle 6th is with one of the inlet port 8th limiting surface 101 - in radial cross-sections (see 4b or 4d ) considered - convex to a longitudinal center axis running in an inflow direction x L6 the inlet nozzle 6th arched and rotationally symmetrical. This forms the longitudinal center axis L6 the inlet nozzle 6th also an axis of rotation D4 of the electric motor 4th , around which an outrunner 4a of the electric motor 4th rotates on which the fan wheel 3 is attached.

The surface 101 the inlet nozzle 6th has radial circumferential geometric irregularities 102a , 102b and 102c which are only indicated by way of example. Because of these geometric irregularities 102a , 102b , 102c is the mentioned rotational symmetry of the surface 101 canceled. These geometric irregularities 102a , 102b , 102c are in the 4a until 4d Shown in detail are in the 1 only indicated schematically and are in the 3 not shown in order to enable the schematic representation of an embodiment variant there.

The irregularities 102a , 102b , 102c are as wells 103a , 103b , 103c formed which are equidistant from the longitudinal center axis L6 are arranged.

According to one embodiment, it is also provided that the irregularities are raised 202a , 202b to train. This is in the 3 indicated by way of example with dashed lines.

Likewise, it can be provided according to an embodiment variant, not shown, to design the irregularities partly as elevations and partly as depressions, whereby it is then provided that they are all arranged equidistant from the longitudinal center axis.

Furthermore, the irregularities 102a , 102b , 102c symmetrically, namely regularly distributed on the in the inlet channel 8th pointing surface 101 the inlet nozzle 6th arranged. According to an embodiment variant not shown, an asymmetrical, namely irregularly distributed arrangement of the irregularities can alternatively be provided.

It is also the case in the 3 The embodiment shown is provided, the surveys 202a , 202b by deformations 303a the inlet nozzle or through attachments 303b to build. In particular, it is provided here that the surveys 202a , 202b to form a spherical segment.

In the case of the 1 until 4d The first embodiment shown is provided, the depressions 103a , 103b , 103c to form by deformations in the form of dents and to form them in particular in the shape of a hollow spherical segment. According to an embodiment variant, not shown, it can also be provided that the depressions are designed as bores.

According to the 1 until 4d The first embodiment variant illustrated, the irregularities are geometrically designed and arranged geometrically distributed in such a way that a boundary layer GS one through the inlet nozzle 6th flowing air stream LS is influenced in such a way that, in particular, the formation of a Käränsche vortex street is at least hindered and in particular prevented (see 4d ). Thus, through the irregularities 102a , 102b , 102c avoided that certain resonance frequencies are excited by the formation of a Käränsche vortex street, which would lead to noise peaks.

In all embodiment variants, it is provided that the longitudinal axes running in the direction of the elevations or the depressions are each at angles to the longitudinal center axis of the inlet nozzle α1 until α3 between 20 ° and 70 ° and preferably between 30 ° and 60 ° and that preferably the longitudinal axes of all elevations or depressions cut the longitudinal center axis of the inlet nozzle at the same angles α1 until α3 cut.

In the case of the 1 until 4d The first embodiment variant shown extends the longitudinal axes L102a , L102b , L102c of the irregularities 102a , 102b , 102c each at angles α1 , α2 , α3 to the longitudinal central axis L6 . Thus all longitudinal axes intersect L102a , L102b , L102c in one on the longitudinal central axis L6 lying intersection P6 .

In the case of the 1 until 4d The first embodiment shown has the inlet nozzle 6th thirty-five irregularities 102a , 102b , 102c on which as wells 103a , 103b , 103c are formed and which are regularly distributed on the surface 101 the inlet nozzle 6th are arranged.

The inlet nozzle also opens 6th like this in the fan room 10b of the chassis 10 the turbo machine 1 that the inlet nozzle 6th contact-free in an inflow opening 3a of the fan wheel 3 is added, the inlet nozzle 6th with a faceplate 9 of the chassis 10 is connected and wherein the fan wheel 3 via the electric motor 4th with the flange plate 11e of the engine mount 11 of the chassis 10 connected is. This is particularly from the 3 evident. The inlet nozzle 6th is thus the same as for the fan wheel 3 positioned so that this is contact-free in its inflow opening 3a immersed.

List of reference symbols

1

Turbo machine

2

Centrifugal fan

3

Fan wheel

3a

Inflow opening

4th

Electric motor

4a

External runners from 4

5

casing

6th

Inlet nozzle

7th

Fluid space

8th

Inlet port

9

Front panel

9a

annular opening in 9

10

chassis

10a

Engine compartment in 10

10b

Fan room in 10

11

Engine mount

11a-11d

Arm of 11

11e

Flange plate from 11

101

Surface of 6

102a-102c

geometric irregularity

103a-103c

Indentations

202a, 202b

Elevation

303a

deformation

303b

Essay

D4

Axis of rotation D4 of the electric motor 4

GS

Boundary layer

LS

Air flow through 6

L6

Longitudinal central axis of the inlet nozzle 6

L102a - L102c

Longitudinal central axis of 102a-102c

P6

Intersection on L6

α1-α3

Angle between L102a-L102c and L6

Claims (10)

Inlet nozzle (6) for a turbomachine (1), in particular for a radial fan (2) or a diagonal fan, - wherein the inlet nozzle (6) surrounds an inlet channel (8) in a ring and - the inlet nozzle (6) with one of the inlet channel (8 ) delimiting surface (101), viewed in radial cross-sections, is essentially convex to a longitudinal center axis (L6) of the inlet nozzle (6) running in an inflow direction (x) and is designed to be rotationally symmetrical, characterized in that the surface (101) of the inlet nozzle ( 6) has geometric irregularities (102a, 102b, 102c) circumferentially, - the rotational symmetry of the surface (101) being canceled by the geometric irregularities (102a, 102b, 102c). Inlet nozzle after Claim 1 , characterized in that the irregularities (102a, 102b, 102c) are formed as elevations (202a, 202b) and / or depressions (103a, 103b, 103c) which are arranged equidistant from the longitudinal center axis (L6). Inlet nozzle after Claim 1 , characterized in that the irregularities (102a, 102b, 102c) are arranged symmetrically or asymmetrically to the longitudinal center axis (L6). Inlet nozzle after Claim 2 , characterized in that the elevations (303a) are formed by deformations of the inlet nozzle (6) or by attachments (303b) and that these are in particular formed in the shape of spherical segments. Inlet nozzle after Claim 2 , characterized in that the depressions (103a, 103b, 103c) are formed by deformations or bores and that the depressions (103a, 103b, 103c) are designed in particular in the shape of a hollow spherical segment. Inlet nozzle according to at least one of the preceding claims, characterized in that the irregularities (102a, 102b, 102c) are geometrically designed and are arranged geometrically distributed in such a way that a boundary layer (GS) of an air flow (LS) is influenced and that in particular an emergence a Käränsche vortex street is at least hindered and in particular prevented. Inlet nozzle after Claim 2 , characterized in that longitudinal axes extending in the direction of the elevations (202a, 202b, 303a, 303b) or the depressions (103a, 103b, 103c) (L102a-L102c) intersect the longitudinal center axis (L6) of the inlet nozzle (6) at angles α1 to α3 between 20 ° and 70 ° and preferably between 30 ° and 60 ° and that preferably the longitudinal axes (L102a-L102c) of all elevations (202a , 202b, 303a, 303b) or depressions (103a, 103b, 103c) intersect the longitudinal center axis (L6) of the inlet nozzle (6) at equal angles α1 to α3. Inlet nozzle according to at least one of the preceding claims, characterized in that the inlet nozzle (6) has at least 15, preferably at least 25 and particularly preferably with at least 35 irregularities (102a, 102b, 102c), which in particular are depressions (103a, 103b, 103c) are formed and which are in particular arranged regularly. Turbomachine (1), in particular radial fan (2), comprising - a fan wheel (3), - an electric motor (4) and - a housing (5), - the fan wheel (3) being driven by the electric motor (4), - wherein the housing (5) comprises an inlet nozzle (6) and a fluid space (7) opening towards the inlet nozzle (6) and - wherein the fan wheel (3) is received in the fluid space (7), characterized in - that the inlet nozzle (6) after at least one of the Claims 1 until 8th is trained. Turbo machine (1) after Claim 9 , characterized in that the inlet nozzle (6) opens into a fan space (10b) of a chassis (10) of the turbomachine (1) in such a way that the inlet nozzle (6) is received without contact in an inflow opening (3a) of the fan wheel (3), wherein the inlet nozzle (6) is connected to a front plate (9) of the chassis (10) and wherein the fan wheel (3) is connected via the electric motor (4) to a flange plate (11e) of a motor support (11) of the chassis (10) .

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