Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
  • F01D5/02—Blade-carrying members, e.g. rotors
  • F01D5/04—Blade-carrying members, e.g. rotors for radial-flow machines or engines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/26—Rotors specially for elastic fluids
  • F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
  • F04D29/281—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps for fans or blowers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/26—Rotors specially for elastic fluids
  • F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
  • F04D29/30—Vanes
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/26—Rotors specially for elastic fluids
  • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
  • F04D29/38—Blades
  • F04D29/384—Blades characterised by form
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2240/00—Components
  • F05D2240/20—Rotors
  • F05D2240/30—Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor
  • F05D2240/303—Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor related to the leading edge of a rotor blade
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2240/00—Components
  • F05D2240/20—Rotors
  • F05D2240/30—Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor
  • F05D2240/304—Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor related to the trailing edge of a rotor blade
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2250/00—Geometry
  • F05D2250/10—Two-dimensional
  • F05D2250/18—Two-dimensional patterned
  • F05D2250/181—Two-dimensional patterned ridged
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2250/00—Geometry
  • F05D2250/10—Two-dimensional
  • F05D2250/18—Two-dimensional patterned
  • F05D2250/182—Two-dimensional patterned crenellated, notched
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2250/00—Geometry
  • F05D2250/10—Two-dimensional
  • F05D2250/18—Two-dimensional patterned
  • F05D2250/183—Two-dimensional patterned zigzag
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2250/00—Geometry
  • F05D2250/10—Two-dimensional
  • F05D2250/18—Two-dimensional patterned
  • F05D2250/184—Two-dimensional patterned sinusoidal
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2250/00—Geometry
  • F05D2250/60—Structure; Surface texture
  • F05D2250/61—Structure; Surface texture corrugated
  • F05D2250/611—Structure; Surface texture corrugated undulated

Definitions

• the invention relates to a blade for the impeller of a fan, in particular an axial fan, diagonal fan or radial fan.
• the invention relates to an impeller equipped with corresponding blades as well as an axial fan or diagonal fan or radial fan, each with an impeller equipped with corresponding blades.
• the present invention is based on the objective of designing and further developing blades for the impeller of a fan, in particular an axial fan, diagonal fan or radial fan, in such a way that the acoustics are improved during the operation of such a fan, in particular the noise emissions are reduced.
• the wing has, among other things, a wavy leading edge and a wavy trailing edge, wherein the waves at the leading edge have a longer wavelength than the waves at the trailing edge.
• the wavelength of the waves at the leading edge is at least 1.5 times greater than the wavelength of the waves at the trailing edge.
• the wavelength of the waves at the leading edge is 2 to 10 times greater than the wavelength of the waves at the trailing edge.
• 5 to 10 wave crests are evenly or unevenly distributed across the span at the leading edge.
• 5 to 50 waves are evenly or unevenly distributed across the span at the trailing edge, whereby it is not necessary for the waves to extend over the entire leading edge and/or the entire trailing edge. It is sufficient if the waves are preferably formed in an area facing away from the hub or hub ring.
• the wavelength of the waves at the leading edge increases from the wingtip or cover ring towards the hub or hub ring. Additionally, the amplitude of the waves can also increase in the same way. The wavelength and/or amplitude of the waves increase at the trailing edge from the hub or hub ring towards the wingtip or cover ring.
• the features at the trailing edge can be called spikes, a term used in the broadest sense.
• the spikes at the trailing edge differ from the waves at the leading edge by their shorter wavelength relative to the amplitude or wave/spike height, and possibly also by steeper flanks and more pointed wave crests.
• the free ends of the waves or teeth can be more or less sharp-edged. For safe handling during installation, it is advantageous if their free ends are rounded or flattened. It is also conceivable that the teeth are coated with a protective film, varnish, etc.
• the invention relates primarily to the design of the leading and trailing edges of the wing. Furthermore, the wing has a three-dimensionally twisted shape. It is also advantageous if the wing, while three-dimensionally twisted, is not corrugated within itself. This measure also reduces noise emissions.
• the blade is intended for an axial or diagonal fan, it is further advantageous if the blade tips are equipped with so-called winglets, namely end-facing bends or rounded edges that curve from the pressure side towards the suction side.
• winglets are well known from aviation. This measure also reduces noise emissions and may increase performance.
• the waves extend – both along the leading and trailing edges – at least across part of the wingspan. It is also conceivable that the waves are zonal or formed in groups with different wavelengths and/or amplitudes.
• the wing can be made of different materials, for example sheet metal.
• the blades can be manufactured from plastic using injection molding or from aluminum using die casting, resulting in a particularly simple design. If the blade is made of sheet metal, it is preferably assembled into an impeller by stamping or laser cutting, followed by embossing, joining/welding, interlocking, etc., which is then used in an axial fan, diagonal fan, or centrifugal fan.
• the impellers are designed and manufactured according to requirements, with the blades of an axial fan extending outwards from a hub to a free end.
• the blades When used in a radial fan, the blades extend between a hub ring and a cover ring and are firmly connected to both.
• the same principles apply as with the previously described fan types, since the primary goal is to reduce noise emissions. in particular, it is about reducing leading edge and trailing edge noise through measures that relate to both the leading edge and the trailing edge.
• FIG. 1 shows a perspective view of an impeller 1 of an axial fan according to the invention.
• Five blades 2 are attached to a hub 3.
• Other numbers of blades are also conceivable for such an impeller, advantageously three to nine blades.
• the impeller 1 is manufactured from fiber-reinforced plastic by injection molding. Other manufacturing methods are also conceivable, for example, aluminum die casting or a welded sheet metal construction.
• the impeller 1 is shown as a one-piece impeller; however, it can also be assembled from individual blades with a hub to form an impeller or be a complete die-cast rotor, wherein parts of the motor rotor are integrally connected to the impeller.
• the wings 2 have a leading edge region 6 and a trailing edge region 7.
• the leading edge regions 6 and the trailing edge regions 7 of the wings each connect the printed sides 28 of the wings 2 and the in Fig. 3
• the suction surfaces 29 of the wings 2 are recognizable.
• a wingtip 5 is formed at the radially outer end.
• a waviness is visible on the leading edge region 6 of the wings 2, with approximately seven wave crests unevenly distributed over the wingspan.
• a waviness is also formed on the trailing edge region 7, with the waviness being jagged at the trailing edge.
• the wavelength of the waviness on the trailing edge region 7 is significantly shorter than that of the waviness on the leading edge, at least by a factor of 1.5.
• thirteen wave crests or jagged edges are distributed over the wingspan on the trailing edge region 7.
• Fig. 2 is the embodiment according to Fig. 1
• the axial plan view from the downstream side is shown.
• the wings 2 have a three-dimensional, twisted shape but are not corrugated; that is, a planar section through such a wing 2 would show no corrugation.
• the corrugation is visible at the leading edge region 6 and, in a jagged pattern, at the trailing edge region 7.
• the wingtips 5 have winglets that are curved from the pressure side to the suction side to further improve acoustics.
• This illustration also clearly shows that the wavelength of the corrugation at the leading edge region 6 is significantly larger than that at the trailing edge region 7, advantageously by a factor of about two to ten. This ratio has proven to be Achieving a low noise level has proven particularly advantageous.
• Fig. 3 is the embodiment according to Fig. 1 and Fig. 2
• the image is shown in an axial top view from the inflow side.
• the suction sides 29 of the blades 2 are visible in this view.
• the direction of rotation of the impeller 1 is clockwise in this view.
• the blade tips 5 at the leading edge regions 6 of the blades lead the blades 2 in the direction of rotation; the blades 2 are forward-curved. This is advantageous, especially in a radially outer area, for low noise levels and pressure stability.
• the wavy, serrated trailing edge region 7 of the blades has a sharp separation edge at the transition to the blade suction side 29, which is particularly advantageous for low trailing edge noise.
• Fig. 4 The figure shows, in axial plan view, seen from the downstream side, a blade 2 of the impeller according to the Figs. 1 to 3 with additional schematically represented details.
• the partial diameter 10 is shown for each wave crest and each wave trough of the waves on the leading edge region 6 of the wing 2.
• the wavelength 11 ( ⁇ w) of the corrugated leading edge region 6 increases from the wingtip 5 (at the outer diameter RA ) to the hub 2 (at the hub diameter RN ).
• the wavelength 12 ( ⁇ z) of the corrugated or serrated trailing edge region 7 is smaller by a factor of 1.5 - 3 than the wavelength 11 ( ⁇ w) of the corrugated leading edge region 6 and decreases from the wingtip 5 to the hub 2. It can also be seen that the trailing edge region 7 is not corrugated or serrated in a region near the hub 3.
• Fig. 4a shows a detail from Fig. 4 at the wing trailing edge region 7. It is a wavelength 12 ( ⁇ z) of the waviness of the wing trailing edge region 7.
• the wavelength 12 ( ⁇ z) is shown, which can be measured from wave crest to wave crest or from wave trough to wave trough.
• the wavelength 12 ( ⁇ z) can vary over the span of the wing trailing edge region 7.
• the height 21 (Hz) of the waves or peaks on the wing trailing edge region 7 is also shown. It corresponds approximately to twice the amplitude of a ripple.
• Hz can also vary over the span of the wing trailing edge region 7, but in this embodiment, it is advantageously kept approximately constant over a wide range.
• a relatively small radius of curvature ⁇ 0.3*Hz is formed at the wave crests on the wing trailing edge region 7, which gives this ripple a more jagged appearance.
• Fig. 4b shows a detail of the Fig. 4 at the wing leading edge region 6.
• a wavelength 11 ( ⁇ w) of the waviness of the wing leading edge region 6 is shown, which can be measured from crest to crest or from trough to trough.
• the wavelength 11 ( ⁇ w) is variable over the span of the wing leading edge region 6.
• the height or twice the amplitude 22 (Hw) of the waves at the wing leading edge region 6 is also shown. It corresponds approximately to twice the amplitude of a waviness.
• the wave crests can be, for example, in an axial view as Fig. 4b
• the wave troughs are connected by a line 24 and by a line 23. The distance between these two lines corresponds approximately to Hw, which in the exemplary embodiment is approximately constant over the span of the wing leading edge region 6.
• FIG. 5 Figure 1 shows the sound power level of a fan with an impeller according to the invention compared to an impeller with only a serrated trailing edge according to the prior art, at constant speed and variable volume flow.
• the sound power level is significantly reduced by the design according to the invention over a wide range of volume flow rates.
• FIG. 6 Figure 1 shows a perspective view of an embodiment of an impeller 1 of a radial fan according to the invention.
• the exemplary embodiment is made of sheet metal.
• the five wings 2 are manufactured from sheet metal by laser cutting and embossing. They are welded to the hub 3 and the cover ring 4.
• a waviness is visible on the leading edge region 6 of the wings 2 along the silhouette line, with approximately eight wave crests distributed more or less evenly over the wingspan.
• a distinctly wavy, rather jagged design is visible on the wing trailing edge region 7, which is superimposed on a second waviness, comparable in wavelength and wave amplitude to the waviness of the leading edge region 6.
• Approximately 48 waves or jagged edges are distributed over the wingspan along the trailing edge region 7. It is particularly advantageous that significantly more waves or jagged edges are formed on the wing trailing edge region 7 than waves on the wing leading edge region 6; in the exemplary embodiment, six times as many, and advantageously two to ten times as many.
• Fig. 7 shows in a side view the embodiment according to Fig. 6 It consists of a hub 3, 5 blades 2, and a cover ring 4.
• the cover ring 4 has an air inlet opening (right) through which air is drawn in during operation of the fan.
• the blades 2 have a three-dimensional, twisted shape.
• the blade pressure sides 28 and the blade suction sides 29 do not run parallel to the axis of rotation of the impeller 1 over a considerable area.
• Such a three-dimensional design is advantageous for the airflow, efficiency, and acoustics of a fan with the impeller 1.
• the delicate serrations or waves on the trailing edge regions 7 are clearly visible.
• the waviness on the leading edge regions 6 is also visible. This has a significantly longer wavelength than the serrated waviness on the blade trailing edge region 7.
• Fig. 8 shows a single wing 2 of the embodiment from the Fig. 6 and 7 Viewed from the printed side 28.
• the blade 2 is made of sheet metal in two steps: laser cutting and embossing. It has a corrugated leading edge area 6 and a corrugated or serrated trailing edge area 7.
• the corrugation at the leading edge area 6 reduces the rotational noise caused by airflow disturbances.
• the serrated corrugation at the trailing edge area 7 reduces or eliminates trailing edge noise. Achieving a thin trailing edge on blades manufactured from sheet metal in this way is often complex, which is why the technology of The reduction of trailing edge noise is particularly suitable due to a corrugated or serrated design.
• the blades 2 are welded to the hub 3 and the cover ring 4.
• Other connections are also conceivable (e.g., tabs).
• Fig. 9 shows wing 2 according to Fig. 8
• the entire surfaces of the pressure sides 28 and suction sides 29 of the vanes 3 exhibit a corrugation embossed into the sheet metal vane.
• the three-dimensional, twisted shape is clearly visible.
• This three-dimensional, twisted shape and the embossed corrugation also stiffen the vane 2; that is, the embossed corrugation has a beneficial effect on the strength and dimensional stability of the vane 2.
• Fig. 10 shows a detailed view of wheel 1 according to the Fig. 6 and 7 Viewed from the side. It is clearly visible that the wavelengths of the waves or spikes at the trailing edge region 7 are considerably smaller than the wavelengths of the waviness at the leading edge region 6, specifically by a factor of approximately 6 in the exemplary embodiment.
• Fig. 11 Figure 28 viewed from the printed side, shows the wing 2 of a further embodiment with centering devices, where the wing 2 is shown in its developed state, i.e., in its sheet metal blank before embossing.
• the finished wing 2 is produced from this blank by embossing.
• the wavy/jagged shape of the trailing edge area 7 is already clearly visible during the blanking process.
• the embossing die does not have the jagged edges of the trailing edge area 7, as they are already present during blanking. This is an advantage, as these delicate structures do not need to be formed in the embossing tool.
• the waviness of the leading edge area 6 is also already visible on the flat blank.
• Various centering devices 18, 19 are provided at the hub-side end 9 of the wing 2 and at the cover ring-side end 13 of the wing 2.
• the semicircular centering devices 19 are located approximately in the middle.
• the square centering devices 18 serve to position the wing 2 in the embossing tool, and the square centering devices 18 serve to position the wing 2 with respect to the hub and cover ring during the welding process.
• Fig. 12 shows wing 2 according to Fig. 11 with representations of the wavelengths, where the wing, as in Fig. 11 , shown before embossing as a sheet metal blank.
• a wavelength 11 ( ⁇ w) at the leading edge region 6 of the wing and a wavelength 12 ( ⁇ z) at the trailing edge region 7 are indicated.
• the wavelength 11 ( ⁇ w) is also superimposed on the wavelength 12 ( ⁇ z) at the trailing edge region 7, since the wavelength 11 ( ⁇ w) is pronounced over the entire wing 2 and its pressure side 28 and its suction side 29 (cf. Fig. 15
• the smaller wavelength of the serrations at the trailing edge region 7 is denoted by ⁇ z.
• ⁇ w is approximately 6 times ⁇ z; a factor of 2-10 is advantageous.
• Fig. 13 shows a detailed view of the Fig. 12 Regarding the trailing edge region 7 of the blade.
• the height 21 (Hz) of the waves or serrations on the trailing edge region 7 of the blade is advantageously at least as large as the wavelength 12 ( ⁇ z) of the waves or serrations on the trailing edge region 7 of the blade, preferably at least 1.4* ⁇ z.
• the serrations or waves on the trailing edge region 7 of the blade thus have a relatively large height compared to their wavelength.
• ⁇ z is advantageously not greater than twice the thickness of the sheet metal or the thickness of the blade 2 at its trailing edge region 7, particularly in the case of sheet metal blades, preferably not greater than 1.5 times this thickness, in order to minimize the sound level of a fan with an impeller with blades 2 in conjunction with the corrugated leading edge region 6 of the blade.
• Fig. 14 shows a detailed view similar to Fig. 13 , relating to the trailing edge region 7 of the wing, where part of a three-dimensionally embossed wing 2 is shown.
• the waves or serrations are not pointed at their outer end (wave crest) but flattened. This reduces the risk of damage to the serrations as well as the risk of injury when handling the impeller 1.
• Sheet metal wings with corrugated/serrated trailing edge regions 7 are advantageously Powder-coated or painted. This softens sharp edges and further reduces the risk of injury.
• Fig. 15 shows a detailed cross-sectional and side view of wheel 1 according to Fig. 6 and 7
• the wing 2 extends between the hub 3 and the cover ring 4.
• the outflow end 16 of the cover plate and the outflow end 15 of the base plate are curved in such a way that the outlet area of the impeller 1 is increased, thereby improving the static efficiency.
• the wing pressure side 28 and the unseen wing suction side 29 exhibit this waviness.
• the wavelength of this waviness on the wing pressure sides 28 and the wing suction sides 29 is equal to or similar to the wavelengths of the wing leading edge regions 6.
• the waviness can extend to the wing trailing edge regions 7, where it then appears superimposed on the waves/sharps of the wing trailing edge regions 7, which have a significantly shorter wavelength.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

Family

ID=63035822

Family Applications (1)

Country Status (8)

Families Citing this family (14)

Citations (2)

Family Cites Families (13)

• 2017
  • 2017-07-18 DE DE102017212231.5A patent/DE102017212231A1/de active Pending
• 2018
  • 2018-06-18 CN CN202512007678.3A patent/CN121738942A/zh active Pending
  • 2018-06-18 EP EP18746087.8A patent/EP3655664B1/de active Active
  • 2018-06-18 JP JP2020501817A patent/JP7219748B2/ja active Active
  • 2018-06-18 CN CN201880059989.XA patent/CN111094758A/zh active Pending
  • 2018-06-18 WO PCT/DE2018/200063 patent/WO2019015729A1/de not_active Ceased
  • 2018-06-18 SI SI201831293T patent/SI3655664T1/sl unknown
  • 2018-06-18 ES ES18746087T patent/ES3058700T3/es active Active
  • 2018-06-18 US US16/631,500 patent/US11035233B2/en active Active

Patent Citations (2)

Also Published As

Similar Documents

Legal Events