EP2811170A1 - Radial fan - Google Patents

Abstract

In a radial fan (1), comprising a housing (4) and an impeller (3) arranged in the housing (4) with an impeller outer diameter (2 · r LR) which is rotatable about an axis of rotation (2), and the housing has an inlet opening a channel (5) which is formed between the wall of the housing (4) arranged radially in relation to the axis of rotation (2), the end walls of the housing (4) and the impeller (3), and an outlet opening (7) has for the air, and the channel (5) has a smallest radial width in the region of a tongue (6), the wall profile of the channel (5) in the radial direction with respect to the axis of rotation (2) in the range 0 ° ¤ ¤ ¤ ¤ Õ SE = 200 ° in the form of a first, non-linear spiral segment, the first, non-linear spiral segment (S) after a circular segment with respect to the axis of rotation (2) eccentric center is followed by a second, linear spiral segment (BS1), and the second, linear spiral segment (BS 1) after a circular segment with respect to the axis of rotation (2) eccentric center is followed by a third, non-linear spiral segment (BS2).

Description

Technical area

The invention relates to a radial fan according to the preamble of claim 1.

State of the art

In centrifugal fans with axial inflow and radial outflow usually spiral housing are provided, which serve the speed delay, the air duct and the air deflection.

From the DE 10 2009 033 776 A1 a radial fan housing is known in which the housing has a first wall portion with non-linear extension, in particular in the form of a logarithmic extension, and a second wall portion with linear extension.

The DE 32 38 913 C2 discloses a housing which expands in a first region corresponding to a logarithmic spiral, extends in a second region equidistant from the impeller, and in a third region spirally expands again to the air outlet.

In the US Pat. No. 6,439,839 B1 discloses a radial fan whose housing increases in a first region at a smaller angle than that of a continuous Archimedean spiral, and a second region at a greater angle than this Archimedean spiral increases.

By use, the radial fan described in more detail below is also known. The radial fan has an impeller with an impeller outer diameter Da, which is rotatably mounted in a housing and can be driven by an electric motor arranged in the axial direction of the impeller. Between the radially arranged wall of the housing and the impeller, a channel is formed, which widens in dependence of an angle to the beginning of the channel to an outlet. The beginning of the channel (φ = 0 °) is defined by the narrowest area between the impeller and a tongue

1. 1. 0° ≤ ϕ ≤ 30° - Kreisbogen mit in Bezug auf die Drehachse des Laufrads versetztem Mittelpunkt
2. 2. 30° < ϕ ≤ 219° - lineare Zunahme des Spiralradius mit dem Winkel ϕ
3. 3. tangentialer Übergang in Gestalt eines Kreissegments mit versetztem Mittelpunkt in Bezug auf die Laufraddrehachse
4. 4. 219° < ϕ ≤ 289° - quadratische Zunahme des Spiralradius (Polynom 2. Grades)
5. 5. 289° ≤ ϕ ≤ 309° - Kreisbogen mit versetztem Mittelpunkt in Bezug auf die Laufraddrehachse
6. 6. Gerade als Austritt

The inner boundary of the channel is defined by the outer circumference of the impeller. The course of the outer boundary of the channel with respect to the axis of rotation of the impeller consists in the known radial fan of a plurality of spiral segments, which are arranged around the axis of rotation of the impeller:

1. 1. 0 ° ≤ φ ≤ 30 ° - Circular arc with center offset with respect to the axis of rotation of the impeller
2. 2. 30 ° <φ ≤ 219 ° - linear increase of the spiral radius with the angle φ
3. 3. Tangential transition in the form of a circle segment with offset center with respect to the impeller axis of rotation
4. 4. 219 ° <φ ≤ 289 ° - quadratic increase of the spiral radius (2nd degree polynomial)
5. 5. 289 ° ≤ φ ≤ 309 ° - circular arc with offset center in relation to the impeller axis of rotation
6. 6. Just as exit

In addition, a so-called oblique tongue frame side, a vertical oblique tongue on the motor side and a Zargenring provided.

Such conventional radial fans usually have impeller outer diameters Da from 50 mm to 205 mm and fan widths from 24 mm to 150 mm

Presentation of the invention, object, solution, advantages

It is an object of the present invention to provide a radial fan with improved properties, in particular with regard to the formation of noise in a limited space available. Furthermore, an improved radial fan is to be developed from radial vent known configuration and dimension (so by using known prior art) for the corresponding, available space, which has a better efficiency.

This object is achieved by a radial fan with the features of claim 1 and a corresponding method for sizing. Advantageous embodiments are the subject of the dependent claims.

The fact that based on a known radial fan, the housing can be easily adapted to slightly different space conditions, costs for the development of the housing and thus the radial fan can be reduced. Here, the known fan is scaled down with a scaling factor and used as the basis for the dimensioning of a blower according to the invention, as described in the claims. In particular, despite the reduction due to the scale in proportion to use slightly larger wheels. Particularly preferred at a scaling factor of 0.85 are impellers having an impeller outer diameter of 0.9 of the base impeller outer diameter.

Fig. 1

eine schematische Ansicht eines Radiallüfters gemäß dem Ausführungsbeispiel,

Fig. 2

einen Radienverlauf gemäß dem ersten Ausführungsbeispiel,

Fig. 3

einen Radienverlauf gemäß dem zweiten Ausführungsbeispiel,

Fig. 4

einen Radienverlauf gemäß dem dritten Ausführungsbeispiel,

Fig. 5

einen Radienverlauf gemäß dem vierten Ausführungsbeispiel, und

Fig. 6

einen Radienverlauf gemäß dem fünften Ausführungsbeispiel.

In the following the invention will be explained in more detail with reference to the drawing. Show it:

Fig. 1

a schematic view of a radial fan according to the embodiment,

Fig. 2

a radius profile according to the first embodiment,

Fig. 3

a radius curve according to the second embodiment,

Fig. 4

a radius profile according to the third embodiment,

Fig. 5

a radius curve according to the fourth embodiment, and

Fig. 6

a radius curve according to the fifth embodiment.

In the following, a radial fan 1 according to a first embodiment will be described in detail with reference to the drawing. This is a radial fan, which was designed on the basis of a known radial fan, with references to this known radial fan as "base" is received. In the present case, a scaling factor SF _basis of 0.85 and a basic impeller _{outer diameter} 140 mm, ie r _LRBasis = 70 mm, are provided, the base radial fan being designed in a previously described manner known by use.

The inventive radial fan 1, which in this case part of a Kraftfahrzeugklimatisierungs- and ventilation system (not shown) with a number of the air supply and discharge air ducts, has a rotatable about a rotation axis 2, driven by an electric motor, not shown impeller 3 in one Housing 4 on. Here, between the impeller 3, which has an impeller outer diameter (2 · r _LR ) of 126 mm, and arranged in the radial direction of the rotation axis 2 wall of the housing 4, a channel 5 is formed, the inner boundary of the outer periphery of the impeller 3 and the outer Border forms the wall of the housing 4.

The housing 4 has an inlet opening, which is presently formed by a circular, concentric with the impeller 3 formed opening, and an outlet opening, which at the channel end with substantially rectangular cross-section is formed. The rotation axis 2 defines a polar coordinate system. The course of the wall of the housing 4 about the axis of rotation 2 results over an angular range of 0 ° to 289 ° as a function r (φ), which will be described in more detail below.

By definition, the channel 5 begins at its narrowest point, at which a tongue 6 of the housing 4 is formed, which separates the beginning of the channel from the channel end within the curved region of the housing 4. The distance of the impeller 3 to the tongue 6 is referred to below as the tongue spacing za, this corresponds to the channel width at the beginning of the channel (measured in the radial direction with respect to the axis of rotation 2 of the impeller 3). Here, the tongue spacing za is determined as a fraction (10.0642%) of the impeller diameter, which applies here. $$\mathrm{za}=\mathrm{0}.\mathrm{100642}\cdot \mathrm{2}\cdot {\mathrm{r}}_{\mathrm{LR}}=\mathrm{12}.\mathrm{681}\mathrm{mm}$$

und unter Berücksichtigung der prozentualen Auslegung des Zungenabstands in Bezug auf den Laufradaußendurchmesser $$\begin{array}{c}\mathrm{r}\left(\mathrm{0}\mathrm{°}\right)={\mathrm{r}}_{\mathrm{LR}}+\mathrm{za}=\left(\mathrm{1}+\mathrm{0},\mathrm{100642}\cdot \mathrm{2}\right)\cdot {\mathrm{r}}_{\mathrm{LR}}\\ =\mathrm{1},\mathrm{201284}\cdot {\mathrm{r}}_{\mathrm{LR}}\end{array}$$

The outer wall results as a curve about the axis of rotation 2 with a radial development r (φ), wherein the angle φ is taken from the lowest channel width, ie at φ = 0 ° applies to the distance of the radial wall of the housing $$\mathrm{r}$$$$\mathrm{}\left(\mathrm{0}\mathrm{°}\right)={\mathrm{r}}_{\mathrm{LR}}+\mathrm{za}$$

and taking into account the percent design of the tongue pitch with respect to the impeller outer diameter $$\begin{array}{c}\mathrm{r}\end{array}$$$$\begin{array}{c}\mathrm{}\left(\mathrm{0}\mathrm{°}\right)={\mathrm{r}}_{\mathrm{LR}}+\mathrm{za}=\left(\mathrm{1}+\mathrm{0}.\mathrm{100642}\cdot \mathrm{2}\right)\cdot {\mathrm{r}}_{\mathrm{LR}}\\ =\mathrm{1}.\mathrm{201284}\cdot {\mathrm{r}}_{\mathrm{LR}}\end{array}$$

Thus, for the present embodiment, the blade diameter of 126 mm (r _LR = 63 mm) results in a tongue spacing of 12.681 mm and further $$\mathrm{r}$$$$\mathrm{}\left(\mathrm{0}\mathrm{°}\right)=\mathrm{1}.\mathrm{201284}\cdot {\mathrm{r}}_{\mathrm{LR}}=75.681\mathrm{mm}$$

Starting from this point S, a first, non-linear spiral segment extends around the rotation axis 2 as the origin of the corresponding polar coordinate system, which satisfies the following equation and reproduces the wall profile with respect to the rotation axis 2 of the impeller 3 $$\mathrm{r}\left(\mathrm{\phi }\right)=\left({\mathrm{r}}_{\mathrm{LR}}+\mathrm{za}\right){\mathrm{e}}^{\mathrm{\phi }\cdot \mathrm{tan\alpha }}\mathrm{in\; the\; <figure-callout\; id="0"\; label="area"\; filenames="imgf0003.png,imgf0004.png"\; state="\{\{state\}\}">area</figure-callout>}\mathrm{0}\mathrm{°}\le \mathrm{\phi }\le {\mathrm{\phi }}_{\mathrm{SE}}$$

Here, the expansion angle α in the present case is 2.2 °. This extension angle and the resulting increased tongue pitch compared to the scaled base spiral allow wheels with larger impeller outer diameters to be installed. For better understanding, the initial angle of an angular range with the end index "0" and the end angle with the end index "E" are indicated. The (final) critical angle φ _{SE of} the first, non-linear spiral segment is presently 70 °, According to the present embodiment is thus valid $$\mathrm{r}\left(\mathrm{\phi }\right)=75.681\mathrm{mm}{\mathrm{e}}^{\mathrm{\phi }\cdot \tan \mathrm{2}.2\mathrm{°}}\mathrm{in\; the\; <figure-callout\; id="0"\; label="area"\; filenames="imgf0003.png,imgf0004.png"\; state="\{\{state\}\}">area</figure-callout>}\mathrm{0}\mathrm{°}\le \mathrm{\phi }\le 70°$$

A first part of this non-linear spiral segment S can be replaced by two circular arc segments in an angle range φ of at most 35 °, the center points of the circle usually not coinciding with the axis of rotation.

It follows in the range φ _SE <φ <φ _BS10 a transition _piece , formed by a circular segment with tangential transitions, the center of the circle usually does not coincide with the axis of rotation 2. Here, the angle of the circle segment is significantly smaller than the angle of the first Transition is, ie $${\mathrm{\phi }}_{\mathrm{BS}10}-{\mathrm{\phi }}_{\mathrm{SE}}"{\mathrm{\phi }}_{\mathrm{SE}}$$

im Bereich ϕ_BS10 ≤ ϕ ≤ ϕ_BS1E The transition piece is followed by a second, linear spiral segment BS1, to which applies $$\mathrm{r}\left(\mathrm{\phi }\right)={\mathrm{SF}}_{\mathrm{Base}}\cdot \left[{\mathrm{r}}_{\mathrm{LRBasis}}+\mathrm{58}.\mathrm{5}\mathrm{mm}\cdot \left(\left(\mathrm{\phi }+\mathrm{71}\mathrm{°}\right)/\mathrm{360}\mathrm{°}\right)\right]$$

in the range φ _BS10 ≤ φ ≤ φ _BS1E

According to the present embodiment, SF _base = 0.85, r _{LR base} = 70 mm and φ _BS1E = 217.783 °.

und hieraus beispielsweise für ϕ = 200° $$\begin{array}{ll}\mathrm{r}\left(200°\right)& =0,85\cdot \left[70\mathrm{mm}+\mathrm{58},\mathrm{5}\mathrm{mm}\cdot \left(\left(200°+\mathrm{71}\mathrm{°}\right)/\mathrm{360}\mathrm{°}\right)\right]\\ & =96,932\mathrm{mm}\end{array}$$

This results $$\begin{array}{ll}\mathrm{r}\left(\mathrm{\phi }\right)& ={\mathrm{SF}}_{\mathrm{Base}}\cdot \left[{\mathrm{r}}_{\mathrm{LRBasis}}+\mathrm{58}.\mathrm{5}\mathrm{mm}\cdot \left(\left(\mathrm{\phi }+\mathrm{71}\mathrm{°}\right)/\mathrm{360}\mathrm{°}\right)\right]\\ & =0.85\cdot \left[70\mathrm{mm}+\mathrm{58}.\mathrm{5}\mathrm{mm}\cdot \left(\left(\mathrm{\phi }+\mathrm{71}\mathrm{°}\right)/\mathrm{360}\mathrm{°}\right)\right]\end{array}$$

and from this, for example, for φ = 200 ° $$\begin{array}{ll}\mathrm{<figure-callout\; id="200"\; label="r"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">r</figure-callout>}\left(200°\right)& =0.85\cdot \left[70\mathrm{mm}+\mathrm{58}.\mathrm{5}\mathrm{mm}\cdot \left(\left(200°+\mathrm{71}\mathrm{°}\right)/\mathrm{360}\mathrm{°}\right)\right]\\ & =96.932\mathrm{mm}\end{array}$$

also beim vorliegenden Skalierungsfaktor SF_Basis von 0,85 mit einem Radius von $$\mathrm{r}={\mathrm{SF}}_{\mathrm{Basis}}\cdot \mathrm{122},\mathrm{633}\mathrm{mm}=0,85\cdot 122,633\mathrm{mm}=104,238\mathrm{mm}$$

wobei der Mittelpunkt des entsprechenden Kreises versetzt zur Drehachse 2 des Laufrades 3 angeordnet ist, schließt sich ein drittes, nicht lineares Spiralsegment BS2 an, für welches gilt $$\mathrm{r}\left(\mathrm{\phi }\right)={\mathrm{SF}}_{\mathrm{Basis}}\cdot \left[{\mathrm{r}}_{\mathrm{E}\mathrm{1}}+\left[\mathrm{1520},\mathrm{3}\cdot \left(\mathrm{\phi }-\mathrm{210}\mathrm{°}\right)/\mathrm{360}\mathrm{°}/\left(26-7,5\cdot \left(\mathrm{\phi }-\mathrm{210}°\right)/70°\right)\right]\mathrm{mm}\right]$$

mit r_E1 = 117,1 mm und im Bereich ϕ_BS20 ≤ ϕ ≤ ϕ_BS2E
wobei ϕ_BS20 = 219° und ϕ_BS2E = 289° betragen.After a circle segment with tangential transitions between φ _BS1E and φ _BS20 and a radius r, which results from $$\mathrm{r}={\mathrm{SF}}_{\mathrm{Base}}\cdot \mathrm{122}.\mathrm{633}\mathrm{mm}$$

So at the present scaling factor SF _basis of 0.85 with a radius of $$\mathrm{r}={\mathrm{SF}}_{\mathrm{Base}}\cdot \mathrm{122}.\mathrm{633}\mathrm{mm}=0.85\cdot 122.633\mathrm{mm}=104.238\mathrm{mm}$$

wherein the center of the corresponding circle is arranged offset from the axis of rotation 2 of the impeller 3, is followed by a third, non-linear spiral segment BS2, for which applies $$\mathrm{r}\left(\mathrm{\phi }\right)={\mathrm{SF}}_{\mathrm{Base}}\cdot \left[{\mathrm{r}}_{\mathrm{e}\mathrm{1}}+\left[\mathrm{1520}.\mathrm{3}\cdot \left(\mathrm{\phi }-\mathrm{210}\mathrm{°}\right)/\mathrm{360}\mathrm{°}/\left(26-7.5\cdot \left(\mathrm{\phi }-\mathrm{210}°\right)/70°\right)\right]\mathrm{mm}\right]$$

with r _E1 = 117.1 mm and in the range φ _BS20 ≤ φ ≤ φ _BS2E
where φ _BS20 = 219 ° and φ _BS2E = 289 °.

This results in a radius, for example, for the 270 ° angle $$\begin{array}{l}\mathrm{r}\left(270°\right)={\mathrm{SF}}_{\mathrm{Base}}\cdot \left[{\mathrm{r}}_{\mathrm{e}\mathrm{1}}+\left[\mathrm{1520}.\mathrm{3}\cdot \left(\mathrm{\phi }-210\mathrm{°}\right)/\mathrm{360}\mathrm{°}/\left(26-7.5\cdot \left(\mathrm{\phi }-\mathrm{210}°\right)/70°\right)\right]\mathrm{mm}\right]\\ =0.85\cdot \left[117.1\mathrm{mm}+\left[\mathrm{1520}.\mathrm{3}\cdot \left(270\mathrm{°}-\mathrm{210}\mathrm{°}\right)/\mathrm{360}\mathrm{°}/\left(26-7.5\cdot \left(270°-\mathrm{210}°\right)/70°\right)\right]\mathrm{mm}\right]\\ =108.450\mathrm{mm}\end{array}$$

And for the final radius r (φ _BS2E ) at the end of the angle range results $$\mathrm{r}\left(289°\right)=113.\mathrm{135}\mathrm{mm}$$

Subsequently, the outlet in the form of an outlet opening 7 is provided from the housing 4, wherein the outlet opens in the tangential direction into a corresponding air channel. Due to the rounded configuration of the tongue 6 and the tongue spacing za> 0 mm, a bifurcation of the channel 5 is provided in the tongue area.

The impeller 3 of the blower 1 according to the first embodiment has a diameter (2 × r _LR = 126 mm) smaller than that of the impeller of the basic fan (2 × r _{LR base} = 140 mm).

For the housing 4 according to the first embodiment, the radius profile r (φ) is up to the end angle of the second, linear _{spiral segment} φ _BS2E = 289 °, at which the outlet begins, in Fig. 2 shown.

According to the embodiment described above, the extension angle α = 2.2 °. In particular, smaller extension angles α are also possible for larger impeller outer diameters. The extension angles α are generally in the range of 0.8 ° to 4.07 °. Specifically, for an impeller scaling factor (ratio of impeller outer diameter to impeller base diameter) of 0.9, the expansion angle is 4.07 ° maximum, for an impeller scaling factor of 0.95, the extension angle is 3.2 ° or less and the impeller scale factor is 1.0 ° Extension angle is maximum 2.4 °.

Further, the critical angle φ _SE in which the radius widens in a non-linear spiral segment is as described above Embodiment 70 °, but it may generally in the range of 70 ° to 200 °, in particular in the range 70 ° to 190 °, lie.

The end angle φ _BS1E is in the range of 215 ° to 222 °, in particular it is about 219 °.

The design described above with reference to a base fan with a base impeller outer diameter of 140 mm and a scaling factor SF _base of 0.85 can also be applied to other base fans. Especially for basic impeller outer diameter from 45 mm to '! 95 mm and scaling factors S _FBasis from 0.8 to 0.95.

The width of the fan is not described in detail above, but it can also be designed based on the width of the base fan, in particular be increased in order to compensate for the reduced spiral volume at an enlargement of the impeller outer diameter. The width applies to the scaled base width, ie the width of the scaled base fan $$1.0\le \mathrm{B}/{\mathrm{SF}}_{\mathrm{Base}}\cdot {\mathrm{B}}_{\mathrm{Base}}\le \mathrm{1}.\mathrm{5}$$

Preferred width enlargement factors B / SF _Basis · B _Basis range from 1.2 to 1.35. The spiral width can be constant over its course, increase linearly or not linearly.

The radii profiles of further exemplary embodiments are described in more detail below with reference to FIGS. 3ff. This results in the radii profiles by the formulas given above in conjunction with the following parameters.

• Basis-Laufradaußendurchmesser 2 · r_LRBasis 140 mm
• Laufradaußendurchmesser 2 · r_LR 140 mm
• Skalierungsfaktor SF_Basis 0,95
• Erweiterungswinkel α 4,05
• Erstes Spiralsegment - Endwinkel ϕ_SE 170°

The in Fig. 3 The blower according to the second exemplary embodiment represented by the course of the radii is based on the following dimensions and parameters:

• Basic impeller _{outer diameter} 2 · r _{LR base} 140 mm
• Impeller outer diameter 2 · r _LR 140 mm
• Scaling factor SF _basis 0.95
• Extension angle α 4.05
• First spiral segment - end angle φ _SE 170 °

• Drittes Ausführungsbeispiel (siehe Fig. 4)
  • Basis-Laufradaußendurchmesser 2 · r_LRBasis 140 mm
  • Laufradaußendurchmesser 2 · r_LR 126 mm
  • Skalierungsfaktor SF_Basis 0,8
  • Erweiterungswinkel α 3,1
  • Erstes Spiralsegment - Endwinkel ϕ_SE 200°
• Viertes Ausführungsbeispiel (siehe Fig. 5)
  • Basis-Laufradaußendurchmesser 2 · r_LRBasis 140 mm
  • Laufradaußendurchmesser 2 · r_LR 126 mm
  • Skalierungsfaktor SF_Basis 0,82
  • Erweiterungswinkel α 0,8
  • Erstes Spiralsegment - Endwinkel ϕ_SE 70°
• Fünftes Ausführungsbeispiel (siehe Fig. 6)
  • Basis-Laufradaußendurchmesser 2 · r_LRBasis 140 mm
  • Laufradaußendurchmesser 2 · r_LR 126 mm
  • Skalierungsfaktor SF_Basis 0,85
  • Erweiterungswinkel α 4,07
  • Erstes Spiralsegment - Endwinkel ϕ_SE 200°

Such a designed housing has a larger radius in the initial region than a corresponding housing of the conventionally designed scaled base fan. The same applies to all housings according to the following embodiments, which are based on the following dimensions and parameters:

• Third embodiment (see Fig. 4 )
  • Basic impeller _{outer diameter} 2 · r _{LR base} 140 mm
  • Impeller outer diameter 2 · r _LR 126 mm
  • Scaling factor SF _basis 0.8
  • Extension angle α 3.1
  • First spiral segment - end angle φ _SE 200 °
• Fourth embodiment (see Fig. 5 )
  • Basic impeller _{outer diameter} 2 · r _{LR base} 140 mm
  • Impeller outer diameter 2 · r _LR 126 mm
  • Scaling factor SF _basis 0.82
  • Extension angle α 0.8
  • First spiral segment - end angle φ _SE 70 °
• Fifth Embodiment (see Fig. 6 )
  • Basic impeller _{outer diameter} 2 · r _{LR base} 140 mm
  • Impeller outer diameter 2 · r _LR 126 mm
  • Scaling factor SF _basis 0.85
  • Extension angle α 4.07
  • First spiral segment - end angle φ _SE 200 °

Claims (10)

A radial fan (1), comprising a housing (4) and an impeller (3) arranged in the housing (4) and having an impeller outer diameter (2 · r _LR ) which is rotatable about an axis of rotation (2), and the housing has an inlet opening, a Channel (5) which is formed between the wall of the housing (4) arranged in the radial direction with respect to the axis of rotation (2), the end walls of the housing (4) and the impeller (3), and an outlet opening (7) for the Has air, and the channel (5) has a smallest radial width in the region of a tongue (6), and the course of the channel (5) results through a sequence of spiral segments of different courses,
characterized in that
the wall course of the channel (5) is formed in the radial direction with respect to the axis of rotation (2) in the range 0 ° ≦ φ ≦ φ _SE in the form of a first, non-linear spiral segment (S), wherein for the end angle (φ _SE ) of the first, non-linear spiral segment (S) applies $$\mathrm{70}\mathrm{°}\le {\mathrm{\phi }}_{\mathrm{SE}}\le \mathrm{200}\mathrm{°}$$

and applies to the course $$\mathrm{r}\left(\mathrm{\phi }\right)=\left({\mathrm{r}}_{\mathrm{LR}}+\mathrm{za}\right){\mathrm{e}}^{\mathrm{\phi }\cdot \mathrm{tan\alpha }}$$

where za is the smallest radial width of the channel (5) and results from $$\mathrm{za}=\mathrm{0}.\mathrm{100642}\cdot \mathrm{2}\cdot {\mathrm{r}}_{\mathrm{LR}}$$

and the extension angle (α) is 0.8 ° to 4.07 °.
the first, non-linear spiral segment (S) after a circular segment with tangential transition and with respect to the axis of rotation (2) eccentric center with tangential transition to the circular segment, a second, linear spiral segment (BS1) connects, and
the second, linear spiral segment (BS1) after a circular segment with tangential transition and with respect to the axis of rotation (2) eccentric center with tangential transition, a third, non-linear spiral segment (BS2) connects. Radial fan according to claim 1, characterized in that the first spiral segment (S) in an angular range of 0 ° <φ <35 ° by two circular arc segments is replaceable, whose center is not on the axis of rotation (2). Radial fan according to claim 1, characterized in that
the course of the wall in the radial direction with respect to the axis of rotation (2) in the range φ _BS10 ≤ φ ≤ φ _BS1E in the form of the second, linear _{spiral segment} results $$\mathrm{r}\left(\mathrm{\phi }\right)={\mathrm{SF}}_{\mathrm{Base}}\cdot \left[{\mathrm{r}}_{\mathrm{LRBasis}}+\mathrm{58}.\mathrm{5}\mathrm{mm}\cdot \left(\left(\mathrm{\phi }+\mathrm{71}\mathrm{°}\right)/\mathrm{360}\mathrm{°}\right)\right]$$

with φ _SE <φ _BS10 , SF _basis in the range of 0.8 to 0.95 and r _{LR basis} in the range of 45 mm to 195 mm and 215 ° <φ _BS1E <222 °. Radial fan according to claim 2, characterized in that SF _basis = 0.85, r _LRBasis = 70 mm and φ _BS1E = 217.783 °. Radial fan according to claim 2 or 3, characterized in that the wall course in the radial direction with respect to the axis of rotation (2) in the range φ _BS20 ≤ φ ≤ φ _BS2E in the form of the third, non-linear _{spiral segment} results $$\mathrm{r}\left(\mathrm{\phi }\right)={\mathrm{SF}}_{\mathrm{Base}}\cdot \left[{\mathrm{r}}_{\mathrm{e}\mathrm{1}}+\left[\mathrm{1520}.\mathrm{3}\cdot \left(\mathrm{\phi }-210\mathrm{°}\right)/\mathrm{360}\mathrm{°}/\left(26-7.5\cdot \left(\mathrm{\phi }-\mathrm{210}°\right)/70°\right)\right]\mathrm{mm}\right]$$

with r _E1 = 117.1 mm and in the range φ _BS20 ≤ φ ≤ φ _BS2E
where φ _BS20 = 219 ° and φ _BS2E = 289 °. Radial fan according to claim 4, characterized in that
φ _BS20 = 219.443 ° and φ _BS2E = 289 °, and φ _BS1E = 217.783 °. Radial fan according to one of claims 2 to 5, characterized in that
the extension angle α at a ratio of the impeller outer diameter (2 r _LR ) to the base impeller _{outer diameter} (2 r _LR basis)
0.9 minimum 2.2 and maximum 4.07 °,
from 0.95 minimum 0.8 ° maximum 3.2 °, and
from 1.0 minimum 0.8 ° maximum 2.4 °. Radial fan according to one of the preceding claims, characterized in that
at a scale factor of 0.85, the extension angle α is in the range of 2.2 ° to 4.0 °, and the end angle (φ _SE ) of the first nonlinear spiral segment (S) is in the range of 70 ° to 180 °. Method for dimensioning a radial fan (1) according to one of the preceding claims, wherein the dimensioning is based on a known radial fan whose housing has the following course of the wall: 1. 0 ° ≤ φ ≤ 30 ° - Circular arc with center offset with respect to the axis of rotation of the impeller 2. 30 ° ≤ φ ≤ 219 ° - linear increase of the spiral radius with the angle φ 3. Tangential transition in the form of a circle segment with offset center with respect to the impeller axis of rotation 4. 219 ° ≤ φ ≤ 289 ° - quadratic increase of the spiral radius 5. 289 ° ≤ φ ≤ 309 ° - circular arc with offset center in relation to the impeller axis of rotation 6. Just as exit
whose impeller has a basic impeller _{outer diameter} (2 r _LRBasis ) and a defined _{fan width} ,
this known fan is scaled down with the scaling factor (SF _basis ), whereby the scaling factor (SF _basis ) lies in the range from 0.8 to 0.95,
the wall course of the channel (5) is formed in the radial direction with respect to the axis of rotation (2) in the range 0 ° ≦ φ ≦ φ _SE in the form of a first, non-linear spiral segment (S), wherein for the end angle (φ _SE ) of the first, non-linear spiral segment (S) applies $$\mathrm{70}\mathrm{°}\le {\mathrm{\phi }}_{\mathrm{SE}}\le \mathrm{200}\mathrm{°}$$

and applies to the course $$\mathrm{r}\left(\mathrm{\phi }\right)=\left({\mathrm{r}}_{\mathrm{LR}}+\mathrm{za}\right){\mathrm{e}}^{\mathrm{\phi }\cdot \mathrm{tan\alpha }}$$

where za is the smallest radial width of the channel (5) and results from $$\mathrm{za}=\mathrm{0}.\mathrm{100642}\cdot \mathrm{2}\cdot {\mathrm{r}}_{\mathrm{LR}}$$

and the extension angle (α) is 0.8 ° to 4.07 °,
the first, non-linear spiral segment (S) after a circular segment with tangential transition and with respect to the axis of rotation (2) eccentric center is followed by a second, linear spiral segment (BS1), and the second, linear spiral segment (BS1) after a circular segment with tangential transition and with respect to the axis of rotation (2) eccentric center is followed by a third, non-linear spiral segment (BS2),
wherein the wall course in the radial direction with respect to the axis of rotation (2) in the range φ _BS10 <φ ≤ φ _BS1E in the form of the second, linear _{spiral segment} results from $$\mathrm{r}\left(\mathrm{\phi }\right)={\mathrm{SF}}_{\mathrm{Base}}\cdot \left[{\mathrm{r}}_{\mathrm{LRBasis}}+\mathrm{58}.\mathrm{5}\mathrm{mm}\cdot \left(\left(\mathrm{\phi }+\mathrm{71}\mathrm{°}\right)/\mathrm{360}\mathrm{°}\right)\right]{\mathrm{with\; \phi }}_{\mathrm{SE}}\le {\mathrm{\phi }}_{\mathrm{BS}\mathrm{10}}.$$

SF _basis in the range of 0.8 to 0.95 and r _{LR basis}
in the range of 45 mm to 195 mm and <φ _BS1E <222 °°
and the course of the wall in the radial direction with respect to the axis of rotation (2) in the range φ _BS20 ≤ φ ≤ φ _BS2E in the form of the third, non-linear _{spiral segment} results $$\mathrm{r}\left(\mathrm{\phi }\right)={\mathrm{SF}}_{\mathrm{Base}}\cdot \left[{\mathrm{r}}_{\mathrm{e}\mathrm{1}}+\left[\mathrm{1520}.\mathrm{3}\cdot \left(\mathrm{\phi }-210\mathrm{°}\right)/\mathrm{360}\mathrm{°}/\left(26-7.5\cdot \left(\mathrm{\phi }-\mathrm{210}°\right)/70°\right)\right]\mathrm{mm}\right]$$

with r _E1 = 117.1 mm and in the range φ _BS20 ≤ φ ≤ φ _BS2E
where φ _BS20 = 219 ° and φ _BS2E = 289 °. A method according to claim 8, characterized in that the ratio of the impeller _{outer diameter} (2 r _LR ) to basic impeller _{outer diameter} (2 r _LRBasis ) is in the range of 0.85 to 1.05.

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