Impeller and centrifugal fan with multi-element coupled bionic blades

Abstract

The present invention relates to the field of centrifugal fans, and more particularly to an impeller and centrifugal fan having multi-element coupled bionic blades. The impeller includes a front disc and a rear disc, wherein an air inlet is provided in the middle of the front disc, and a plurality of blades are arranged in an array around the rear disc. The blades include long blades and short blades that are spaced and evenly distributed, and both the long blades and the short blades are sheet metal single-arc multi-element coupled bionic blades. The impeller and centrifugal fan having multi-element coupled bionic blades of the present invention, based on the principles of bionic flow control technology, adopt a streamlined structural feature of the leading edge of the long blades that mimics the outer edge of a shark's tail fin, and a typical curved tooth structure of the leading edge of the feathers of a peregrine falcon's wing that is simulated on the trailing edge of the blade. This improves the low flow rate, low pressure, low efficiency, and high noise commonly found in prior art centrifugal fans.

Description

Technical Field

[0001] The present invention relates to the field of centrifugal fan industry, and in particular to an impeller with multi-element coupled bionic blades and a centrifugal fan. Background Art

[0002] Single-plate backward-inclined centrifugal fans are widely used in residential and industrial buildings for ventilation, cooling, dust removal, and gas circulation in conjunction with other mechanical equipment. With the rapid development of the national economy and various industries, users are constantly putting forward new requirements for fan performance parameters. Traditional single-plate backward-inclined centrifugal fans cannot meet customers' needs for higher flow, higher pressure, high efficiency, and low noise.

[0003] Bionics is an important source of theoretical innovation for humans to promote technological progress by drawing on the achievements of biological evolution. The development of bionics has promoted the progress of flow control technology, thus deriving bionic flow control technology, which is to enhance the flow control effect by learning and imitating the unique functions of organisms or living organisms.

[0004] Whether bionics can be combined to improve the problems of small flow, low pressure, low efficiency and high noise in traditional single-plate backward-inclined centrifugal fans has become an urgent issue to be solved. Summary of the Invention

[0005] The purpose of the present invention is to provide an impeller and a centrifugal fan with multi-element coupled bionic blades, aiming to solve the problems of low flow, low pressure, low efficiency and high noise of single-plate backward-inclined centrifugal fans in the prior art.

[0006] To achieve the above-mentioned object, according to a first aspect of the present invention, an impeller with multi-element coupled bionic blades comprises a front disc and a rear disc, wherein an air suction port is provided in the middle of the front disc, and a plurality of blades are arranged in an array around the rear disc;

[0007] The blades include long blades and short blades that are spaced and evenly distributed, and both the long blades and the short blades are sheet metal single arc multi-coupling bionic blades;

[0008] The long blade includes a long blade leading edge, a long blade trailing edge, a long blade first side edge connected between first ends of the long blade leading edge and the long blade trailing edge, and a long blade second side edge connected between second ends of the long blade leading edge and the long blade trailing edge, the long blade first side edge being a side edge close to the air suction port, and the long blade second side edge being a side edge away from the air suction port;

[0009] The leading edge of the long blade includes a leading edge straight line segment, a first leading edge arc segment, a second leading edge arc segment and a third leading edge arc segment that are tangentially connected in sequence, the first leading edge arc segment and the second leading edge arc segment are inscribed inwardly, the second leading edge arc segment and the third leading edge arc segment are circumscribed outwardly, the leading edge straight line segment is connected to the first side edge of the long blade, and the third leading edge arc segment is connected to the second side edge of the long blade;

[0010] The trailing edge of the long blade includes a first straight line segment of the trailing edge, a first arc segment of the trailing edge, a second straight line segment of the trailing edge, a second arc segment of the trailing edge, a third straight line segment of the trailing edge, a third arc segment of the trailing edge, and a fourth arc segment of the trailing edge, which are connected in sequence. The second straight line segment of the trailing edge, the second arc segment of the trailing edge, the third straight line segment of the trailing edge and the third arc segment of the trailing edge are all connected in sequence in multiple sections. The first straight line segment of the trailing edge is connected to the second side of the long blade, and the fourth straight line segment of the trailing edge is connected to the first side of the long blade.

[0011] Furthermore, the short blade includes a short blade leading edge, a short blade trailing edge, a short blade first side edge connected between the first ends of the short blade leading edge and the short blade trailing edge, and a short blade second side edge connected between the second ends of the short blade leading edge and the short blade trailing edge, the short blade first side edge is a side edge close to the air suction port, and the short blade second side edge is a side edge away from the air suction port;

[0012] The structure of the trailing edge of the short blade is the same as that of the trailing edge of the long blade, and the leading edge of the short blade is perpendicular to the rear disk.

[0013] Furthermore, in the unfolded view of the long blade, the length L6 of the leading edge straight segment is 11.6 mm to 12.1 mm, the radius R3 of the first arc segment of the leading edge is 44.3 mm to 45.5 mm and the arc length is 70 mm to 71.2 mm, the radius R4 of the second arc segment of the leading edge is 36.8 mm to 37.2 mm and the arc length is 9 mm to 9.5 mm, and the radius R5 of the third arc segment of the leading edge is 199 mm to 201 mm and the arc length is 104 mm to 107 mm;

[0014] The length L7 of the first straight line segment of the trailing edge is equal to that of the fourth straight line segment of the trailing edge and is 9 mm to 9.2 mm. The radius R6 of the first arc segment of the trailing edge and the fourth arc segment of the trailing edge are equal to each other and are 1.75 mm to 2.25 mm, and the arc length is equal to each other and is 2.4 mm to 2.6 mm. The length L8 of the second straight line segment of the trailing edge and the length L9 of the third straight line segment of the trailing edge are equal to each other and are 8.7 mm to 8.9 mm. The radius R7 of the second arc segment of the trailing edge is 1.75 mm to 2.25 mm, and the arc length is 5.15 mm to 5.45 mm. The radius R8 of the third arc segment of the trailing edge is 1.1 mm to 1.4 mm, and the arc length is 3.2 mm to 3.4 mm. The distance L10 between the centers of adjacent second arc segments of the trailing edge is 10.4 mm to 10.6 mm, and the distance L11 between the centers of adjacent third arc segments of the trailing edge is 10.4 mm to 10.6 mm.

[0015] The length L12 of the second side of the long blade is 195mm-198mm;

[0016] In the unfolded view of the short blade, the length L3 of the leading edge of the short blade is 123.6 mm-124.5 mm, and the length L5 of the second side of the short blade is 71 mm-72 mm.

[0017] Furthermore, the front disc is set to an arc-shaped structure, the vertical distance L2 between the air suction port and the rear disc is 184mm-186mm, and the vertical distance L4 between the end of the front disc away from the air suction port and the rear disc is 114.5mm-115.5mm;

[0018] The impeller is cut with a plane passing through the central axis of the impeller. The radius R2 of the arc surface of the front disk in the cross section is 80.4mm-81.5mm and the arc length is 117mm-118mm.

[0019] The inlet angle ∠1 when the long blade is installed is 23.5°-24.5°, the inlet angle ∠2 when the short blade is installed is 29.5°-30.5°, the outlet angle ∠3 when the long blade is installed is equal to the outlet angle ∠4 when the short blade is installed and is 27.5°-28°. On the projection surface of the rear disc, the radius R1 of the arc surface of the long blade is 206mm-208mm and the arc length is 194mm-196.4mm, and the radius R15 of the arc surface of the short blade is 206mm-208mm and the arc length is 70mm-72mm;

[0020] The diameter φ1 of the outer circle formed by the outer ends of all long blades and all short blades of the impeller is 450mm, the diameter φ2 of the inner circle formed by the inner ends of all long blades is 259mm-261mm, and the diameter φ3 of the inner circle formed by the inner ends of all short blades is 399mm-381mm;

[0021] With the impeller's rotation direction as the front, the distance L1 between the outermost end of the long blade and the outermost end of the adjacent short blade behind is 65.8mm-66.2mm;

[0022] The diameter φ4 of the air suction port is 292mm-294mm, and 8 long blades and 8 short blades are provided.

[0023] Furthermore, L6 is 11.9mm, R3 is 45mm and the arc length is 70.7mm, R4 is 37mm and the arc length is 9.3mm, R5 is 200mm and the arc length is 105.5mm, L7 is 9.1mm, R6 is 2mm and the arc length is 2.5mm, L8 is 8.8mm, R7 is 2mm and the arc length is 5.3mm, R8 is 1.25mm and the arc length is 3.3mm, L10 is 10.5mm, L11 is 10.5mm, L12 is 196.6mm, L3 is 124 .1mm, L5 is 71.5mm, L2 is 185mm, L4 is 115mm, R2 is 81mm and the arc length is 117.49mm, ∠1 is 23.93°, ∠2 is 30.01°, ∠3 is 27.8°, the radius R1 of the arc surface of the long blade is 207mm and the arc length is 195.17mm, the radius R15 of the arc surface of the short blade is 207mm and the arc length is 70.95mm, φ2 is 260mm, φ3 is 380mm, L1 is 66.03mm, and φ4 is 293mm.

[0024] According to a second aspect of the present invention, a centrifugal fan includes a volute and a collector fixedly arranged in the volute, and also includes the above-mentioned impeller, the impeller is arranged in the volute, and a radial gap is set between the impeller and the collector, and the width L19 of the radial gap is 4.8mm-5.2mm.

[0025] Furthermore, the collector includes a connecting portion, an air guide portion, an air inlet and an air guide port, the air guide portion is fixedly connected to the volute through the connecting portion, the connecting portion is annular and the inner circumference forms the air inlet, and the outlet of the air guide portion forms the air guide port;

[0026] The collector is cut with a plane passing through the central axis of the collector. In the cross section, the air guide portion is set to a single arc structure. The radius R9 of the arc surface of the air guide portion is 76mm-78mm and the arc length is 145mm-148mm.

[0027] From the air inlet to the air guide, the diameter of the air guide portion is configured to gradually decrease and then gradually expand in the direction away from the air inlet. The diameter φ7 of the narrowest part of the air guide portion is 276mm-277mm.

[0028] The diameter φ5 of the air inlet is 424.5mm-427.5mm, the diameter φ6 of the air guide outlet is 283mm-285mm, the vertical distance L13 between the narrowest part of the air guide part and the air inlet is 76mm-77mm, and the vertical distance L14 between the narrowest part of the air guide part and the air guide outlet is 24mm-24.4mm.

[0029] Furthermore, R9 is 77 mm and the arc length is 146.65 mm, φ7 is 276.38 mm, φ5 is 426 mm, φ6 is 284.21 mm, L13 is 76.48 mm, and L14 is 24.16 mm.

[0030] Furthermore, the profile of the volute includes a first diffuser straight segment, a volute tongue segment, a first arc segment, a second arc segment, a third arc segment, a fourth arc segment, and a second diffuser straight segment that are tangentially connected in sequence; the first diffuser straight segment and the second diffuser straight segment enclose an air outlet, and the first arc segment, the second arc segment, the third arc segment, and the fourth arc segment are not cocentric;

[0031] A rectangular coordinate system is established with the center of the impeller as the coordinate origin. When the first diffuser straight segment is located in the third quadrant, the coordinates of the center O2 of the first arc segment are (-21, 39), the radius R11 is 249mm-253mm, and the arc length is 149mm-151mm. The coordinates of the center O1 of the second arc segment are (57, 39), the radius R12 is 326mm-330mm, and the arc length is 483mm-487mm. The coordinates of the center O4 of the third arc segment are (57, -57), the radius R13 is 422mm-428mm, and the arc length is 664mm-670mm. The coordinates of the center O3 of the fourth arc segment are (-21, -57), the radius R14 is 500mm-506mm, and the arc length is 785mm-795mm. Both the first diffuser straight segment and the second diffuser straight segment are arranged perpendicular to the air outlet.

[0032] Furthermore, the width L17 of the air outlet is 288mm-292mm, and the height L18 is 462mm-468mm;

[0033] The radius R10 of the volute tongue segment is 13.5mm-14.5mm and the arc length is 27.4mm-28.6mm. The length L15 of the first diffuser straight segment is 28.7mm-29.3mm. The length L16 of the second diffuser straight segment is 263mm-265mm. The tangent line of the volute tongue segment is drawn with the tangent point of the volute tongue segment and the first arc segment as the tangent point. The angle ∠5 between the tangent line and the first diffuser straight segment is 62°-63.5°.

[0034] The present invention provides an impeller and a centrifugal fan with multi-element coupled bionic blades:

[0035] (1) Due to the presence of a high-pressure impact area at the leading edge of the blade, based on the principle of bionic flow control technology, the leading edge of the long blade adopts a streamlined structural feature that imitates the outer edge of a shark's tail fin, which reduces the impact loss of the blade inlet airflow, the pressure pulsation on the blade surface, and the airflow turbulence, thereby reducing aerodynamic noise. At the same time, the trailing edge of the blade adopts the typical arc-tooth structure feature of the leading edge of the feathers of a peregrine falcon's wing, which can effectively reduce the periodic shedding of the blade tail vortex, thereby minimizing the velocity gradient on the wall, reducing the airflow resistance and the formation of vortexes, improving the performance and efficiency of the fan, and reducing noise. Further, by combining long and short blades, the length, circumferential position arrangement, and installation angle of the long and short blades are designed to improve the problems of impeller inlet blockage and the suppression of separation and backflow inside the impeller flow channel. The blade channel expansion angle is reduced to reduce separation loss and reduce the slip coefficient, thereby improving the fan flow, total pressure, and fan efficiency.

[0036] (2) By designing the aerodynamic profile of the collector (taper angle, arc radius, profile transition continuity, etc.), flow losses are reduced and the uniformity of the inlet airflow is improved. In addition, the collector can accurately match the impeller structure of the multi-coupled bionic blade, further reducing vortex and flow separation, and reducing the impact loss and noise of the airflow on the impeller inlet;

[0037] (3) The arc transition structure of the logarithmic spiral volute profile ensures smooth and efficient airflow in the volute, reduces the impact of the airflow and energy loss, and thus improves the efficiency of the fan; by optimizing the air outlet and the volute tongue section of the volute to match the outlet airflow angle of the bionic blade, the impact loss and separation of the airflow are reduced, the fan's efficient operating range is widened, the total pressure and fan efficiency are improved, and the fan noise is further reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of the centrifugal fan of the present invention;

[0039] Figure 2 Schematic diagram of the volute profile;

[0040] Figure 3 Schematic diagram of the side cross-sectional structure of the volute;

[0041] Figure 4 is a structural diagram of the impeller;

[0042] Figure 5 Schematic diagram of the side cross-sectional structure of the impeller;

[0043] Figure 6 Schematic diagram of the expansion of the long blade;

[0044] Figure 7 Schematic diagram of the expansion of the short blade;

[0045] Figure 8 is a side sectional view of the current collector;

[0046] Figure 9 is a performance curve diagram of the centrifugal fan of the present invention;

[0047] Figure 10 It is a performance curve diagram of the comparison ratio.

[0048] Description of reference numerals:

[0049] Volute 1; first diffuser straight section 11; volute tongue section 12; first arc segment 13; second arc segment 14; third arc segment 15; fourth arc segment 16; second diffuser straight section 17; air outlet 18;

[0050] Impeller 2; long blade 21; long blade leading edge 211; leading edge first arc segment 2111; leading edge second arc segment 2112; leading edge third arc segment 2113; leading edge straight segment 2114; long blade trailing edge 212; trailing edge first straight segment 2121; trailing edge first arc segment 2122; trailing edge second straight segment 2123; trailing edge second arc segment 2124; trailing edge third straight segment 2125; trailing edge third arc segment 2126; trailing edge fourth arc segment 2127; trailing edge fourth straight segment 2128; long blade first side 213; long blade second side 214; front disc 22; rear disc 23; air intake 24; short blade 25; short blade leading edge 251; short blade trailing edge 252; short blade first side 253; short blade second side 254;

[0051] Current collector 3; connecting portion 31; air guide portion 32; air inlet 33; air guide port 34;

[0052] Motor 4; base 5. DETAILED DESCRIPTION

[0053] The present invention is described in detail below with reference to specific embodiments.

[0054] In the present invention, unless otherwise expressly specified and limited, when terms such as "set on", "connected", and "connected" appear, these terms should be understood in a broad sense. For example, they can be fixedly connected, detachably connected, or integrally connected; they can be directly connected or connected through one or more intermediate media. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The directional words that appear in the present invention are to better illustrate the characteristics of the features and the relationship between the features. It should be understood that when the placement direction of the present invention changes, the characteristics of the features and the direction of the relationship between the features also change accordingly. Therefore, the directional words do not constitute an absolute limitation on the characteristics of the features and the relationship between the features in space, but only play a relative limitation role.

[0055] The structural parameters adopted in the present invention are only for illustrating the technical solution of the present invention. That is, based on the basic structural parameters of the present invention, reasonable proportional scaling can be performed in actual production (for example, when the diameter of the impeller is 450 mm, it can be scaled 0.1-30 times, etc.), and such reasonable proportional scaling also falls within the scope of protection of the present invention.

[0056] See also Figure 1-10 According to a first aspect of the present invention, an impeller with multi-element coupled bionic blades, the impeller 2 includes a front disc 22 and a rear disc 23, an air inlet 24 is provided in the middle of the front disc 22, and a plurality of blades are arranged in an array around the rear disc 23;

[0057] The blades include long blades 21 and short blades 25 that are spaced and evenly distributed. The long blades 21 and the short blades 25 are both sheet metal single arc multi-coupling bionic blades.

[0058] The long blade 21 includes a long blade leading edge 211, a long blade trailing edge 212, a long blade first side 213 connected between the first ends of the long blade leading edge 211 and the long blade trailing edge 212, and a long blade second side 214 connected between the second ends of the long blade leading edge 211 and the long blade trailing edge 212. The long blade first side 213 is a side close to the air suction port 24, and the long blade second side 214 is a side away from the air suction port 24.

[0059] The long blade leading edge 211 includes a leading edge straight line segment 2114, a first leading edge arc segment 2111, a second leading edge arc segment 2112, and a third leading edge arc segment 2113, which are sequentially tangentially connected. The first leading edge arc segment 2111 and the second leading edge arc segment 2112 are inscribed inwardly, and the second leading edge arc segment 2112 and the third leading edge arc segment 2113 are circumscribed outwardly. The leading edge straight line segment 2114 is connected to the first side edge 213 of the long blade, and the third leading edge arc segment 2113 is connected to the second side edge 214 of the long blade.

[0060] The long blade trailing edge 212 includes a first trailing edge straight segment 2121, a first trailing edge arc segment 2122, a second trailing edge straight segment 2123, a second trailing edge arc segment 2124, a third trailing edge straight segment 2125, a third trailing edge arc segment 2126, a fourth trailing edge arc segment 2127 and a fourth trailing edge straight segment 2128, which are connected in sequence. The second trailing edge straight segment 2123, the second trailing edge arc segment 2124, the third trailing edge straight segment 2125 and the third trailing edge arc segment 2126 are all connected in sequence in multiple sections. The first trailing edge straight segment 2121 is connected to the second side 214 of the long blade, and the fourth trailing edge straight segment 2128 is connected to the first side 213 of the long blade.

[0061] In this embodiment, the short blade 25 includes a short blade leading edge 251, a short blade trailing edge 252, a short blade first side 253 connected between the first ends of the short blade leading edge 251 and the short blade trailing edge 252, and a short blade second side 254 connected between the second ends of the short blade leading edge 251 and the short blade trailing edge 252. The short blade first side 253 is a side close to the air suction port 24, and the short blade second side 254 is a side away from the air suction port 24.

[0062] The short blade trailing edge 252 has the same structure as the long blade trailing edge 212 , and the short blade leading edge 251 is perpendicular to the rear disk 23 .

[0063] Through the above technical solution, since there is a high-pressure impact area on the leading edge of the blade, according to the principle of bionic flow control technology, the leading edge 211 of the long blade adopts the streamlined structural characteristics of the outer edge of the shark's tail fin, which reduces the impact loss of the blade inlet airflow, the pressure pulsation on the blade surface and the airflow turbulence, and reduces the aerodynamic noise; at the same time, the trailing edge of the blade adopts the typical arc tooth structure characteristics of the leading edge of the feathers of the peregrine falcon's wing, which can effectively reduce the periodic shedding of the blade tail vortex, and thus can minimize the velocity gradient on the wall to the greatest extent, reduce the airflow resistance and the formation of vortex, improve the performance and efficiency of the fan, and reduce noise.

[0064] In this embodiment, in the unfolded view of the long blade 21, the length L6 of the leading edge straight segment 2114 is 11.6 mm to 12.1 mm, the radius R3 of the leading edge first arc segment 2111 is 44.3 mm to 45.5 mm, and the arc length is 70 mm to 71.2 mm, the radius R4 of the leading edge second arc segment 2112 is 36.8 mm to 37.2 mm, and the arc length is 9 mm to 9.5 mm, and the radius R5 of the leading edge third arc segment 2113 is 199 mm to 201 mm, and the arc length is 104 mm to 107 mm. Preferably, L6 is 11.9 mm, R3 is 45 mm, and the arc length is 70.7 mm, R4 is 37 mm, and the arc length is 9.3 mm, and R5 is 200 mm, and the arc length is 105.5 mm.

[0065] The length L7 of the first straight line segment 2121 of the trailing edge is equal to the length L7 of the fourth straight line segment 2128 of the trailing edge and is 9 mm to 9.2 mm. The radius R6 of the first arc segment 2122 of the trailing edge and the fourth arc segment 2127 of the trailing edge are equal to each other and are 1.75 mm to 2.25 mm, and the arc length is equal to each other and is 2.4 mm to 2.6 mm. The length L8 of the second straight line segment 2123 of the trailing edge and the length L9 of the third straight line segment 2125 of the trailing edge are equal to each other and are 8.7 mm to 8.9 mm. The radius R7 of the second arc segment 2124 of the trailing edge is 1.75 mm to 2.25 mm and the arc length is 5.15 mm to 5.45 mm. The radius R8 of the third arc segment 2126 of the trailing edge is 1.1 mm to 1.4 mm. The arc length is 3.2 mm to 3.4 mm, the distance L10 between the centers of adjacent trailing edge second arc segments 2124 is 10.4 mm to 10.6 mm, and the distance L11 between the centers of adjacent trailing edge third arc segments 2126 is 10.4 mm to 10.6 mm; the length L12 of the second side 214 of the long blade is 195 mm to 198 mm; preferably, L7 is 9.1 mm, R6 is 2 mm and the arc length is 2.5 mm, L8 is 8.8 mm, R7 is 2 mm and the arc length is 5.3 mm, R8 is 1.25 mm and the arc length is 3.3 mm, L10 is 10.5 mm, L11 is 10.5 mm, and L12 is 196.6 mm;

[0066] In the unfolded view of the short blade, the length L3 of the leading edge of the short blade is 123.6 mm to 124.5 mm, and the length L5 of the second side of the short blade is 71 mm to 72 mm. Preferably, L3 is 124.1 mm and L5 is 71.5 mm.

[0067] In this embodiment, the front disc 22 is configured as an arc-shaped structure, the vertical distance L2 between the air suction port 24 and the rear disc 23 is 184 mm to 186 mm, and the vertical distance L4 between the end of the front disc 22 away from the air suction port 24 and the rear disc 23 is 114.5 mm to 115.5 mm.

[0068] The impeller is cut with a plane passing through the central axis of the impeller 2. In the cross section, the radius R2 of the arc surface of the front disk 22 is 80.4 mm to 81.5 mm and the arc length is 117 mm to 118 mm.

[0069] The inlet angle ∠1 of the long blade 21 when installed is 23.5°-24.5°, the inlet angle ∠2 of the short blade 25 when installed is 29.5°-30.5°, the outlet angle ∠3 of the long blade 21 when installed is equal to the outlet angle ∠4 of the short blade 25 when installed, and is 27.5°-28°. On the projection surface of the rear disc 23, the radius R1 of the arc surface of the long blade 21 is 206mm-208mm and the arc length is 194mm-196.4mm, and the radius R15 of the arc surface of the short blade 25 is 206mm-208mm and the arc length is 70mm-72mm.

[0070] The diameter φ1 of the outer circle formed by the outer ends of all the long blades 21 and all the short blades 25 of the impeller 2 is 450 mm, the diameter φ2 of the inner circle formed by the inner ends of all the long blades 21 is 259 mm to 261 mm, and the diameter φ3 of the inner circle formed by the inner ends of all the short blades 25 is 399 mm to 381 mm;

[0071] With the rotation direction of the impeller 2 as the front, the distance L1 between the outermost end of the long blade 21 and the outermost end of the adjacent short blade 25 behind is 65.8 mm-66.2 mm;

[0072] The diameter φ4 of the air suction port 24 is 292 mm to 294 mm, and eight long blades 21 and eight short blades 25 are provided.

[0073] Preferably, L2 is 185 mm, L4 is 115 mm, R2 is 81 mm and the arc length is 117.49 mm, ∠1 is 23.93°, ∠2 is 30.01°, ∠3 is 27.8°, the radius R1 of the arc surface of the long blade 21 is 207 mm and the arc length is 195.17 mm, the radius R15 of the arc surface of the short blade 25 is 207 mm and the arc length is 70.95 mm, φ2 is 260 mm, φ3 is 380 mm, L1 is 66.03 mm, and φ4 is 293 mm.

[0074] Through the above technical solution, by further combining long and short blades, the parameters such as the length, circumferential position arrangement and installation angle of the long and short blades are designed, which improves the problems of impeller inlet blockage and suppression of internal separation and backflow of the impeller flow channel, reduces the blade expansion angle to reduce separation loss, and reduces the slip coefficient, thereby improving the fan flow, total pressure and fan efficiency.

[0075] According to a second aspect of the present invention, a centrifugal fan includes a volute 1 and a collector 3 fixedly arranged in the volute 1, and also includes the above-mentioned impeller 2, the impeller 2 is arranged in the volute 1, and a radial gap is provided between the impeller 2 and the collector 3, and the width L19 of the radial gap is 4.8mm-5.2mm.

[0076] In this embodiment, the collector 3 includes a connecting portion 31, an air guide portion 32, an air inlet 33, and an air guide port 34. The air guide portion 32 is fixedly connected to the volute 1 via the connecting portion 31. The connecting portion 31 is annular and has an inner circumference forming the air inlet 33. The outlet of the air guide portion 32 forms the air guide port 34.

[0077] The collector 3 is cut with a plane passing through the central axis of the collector 3. In the cross section, the air guide portion 32 is set to a single arc structure. The radius R9 of the arc surface of the air guide portion 32 is 76mm-78mm and the arc length is 145mm-148mm.

[0078] From the air inlet 33 toward the air guide 34, the diameter of the air guide portion 32 is configured to gradually decrease and then gradually expand in the direction away from the air inlet 33. The diameter φ7 of the air guide portion 32 at its narrowest point is 276 mm to 277 mm.

[0079] The diameter φ5 of the air inlet 33 is 424.5mm-427.5mm, the diameter φ6 of the air guide 34 is 283mm-285mm, the vertical distance L13 between the narrowest point of the air guide portion 32 and the air inlet 33 is 76mm-77mm, and the vertical distance L14 between the narrowest point of the air guide portion 32 and the air guide 34 is 24mm-24.4mm. Preferably, R9 is 77mm and the arc length is 146.65mm, φ7 is 276.38mm, φ5 is 426mm, φ6 is 284.21mm, L13 is 76.48mm, and L14 is 24.16mm.

[0080] Through the above technical solution, in conjunction with the improvement of the impeller 2 and the volute 1, the aerodynamic profile (taper angle, arc radius, profile transition continuity, etc.) of the collector 3 is designed to reduce flow losses and improve the uniformity of the inlet airflow; at the same time, a radial gap is set between the collector 3 and the impeller 2, and the collector 3 is set to accurately match the impeller 2 structure of the multi-coupled bionic blade, further reducing eddy currents and flow separation, and reducing the impact loss and noise of the airflow on the inlet of the impeller 2.

[0081] In this embodiment, the profile of the volute 1 includes a first diffuser straight segment 11, a volute tongue segment 12, a first arc segment 13, a second arc segment 14, a third arc segment 15, a fourth arc segment 16, and a second diffuser straight segment 17, which are tangentially connected in sequence. The first diffuser straight segment 11 and the second diffuser straight segment 17 enclose an air outlet 18, and the first arc segment 13, the second arc segment 14, the third arc segment 15, and the fourth arc segment 16 are not cocentric.

[0082] A rectangular coordinate system is established with the center of the impeller 2 as the coordinate origin. When the first diffuser straight segment 11 is located in the third quadrant, the center O2 coordinates of the first arc segment 13 are (-21, 39), the radius R11 is 249mm-253mm, and the arc length is 149mm-151mm. The center O1 coordinates of the second arc segment 14 are (57, 39), the radius R12 is 326mm-330mm, and the arc length is 483mm-487mm. mm, the coordinates of the center O4 of the third arc segment 15 are (57, -57), the radius R13 is 422mm-428mm and the arc length is 664mm-670mm, the coordinates of the center O3 of the fourth arc segment 16 are (-21, -57), the radius R14 is 500mm-506mm and the arc length is 785mm-795mm, and the first diffuser straight segment 11 and the second diffuser straight segment 17 are both arranged perpendicular to the air outlet 18.

[0083] Preferably, a rectangular coordinate system is established with the center of the impeller 2 as the coordinate origin. When the first diffuser straight segment 11 is located in the third quadrant, the coordinates of the center O2 of the first arc segment 13 are (-21, 39), the radius R11 is 251 mm, and the arc length is 150 mm. The coordinates of the center O1 of the second arc segment 14 are (57, 39), the radius R12 is 328 mm, and the arc length is 485 mm. The coordinates of the center O4 of the third arc segment 15 are (57, -57), the radius R13 is 425 mm, and the arc length is 667 mm. The coordinates of the center O3 of the fourth arc segment 16 are (-21, -57), the radius R14 is 503 mm, and the arc length is 790 mm.

[0084] In this embodiment, the width L17 of the air outlet 18 is 288 mm to 292 mm, and the height L18 is 462 mm to 468 mm;

[0085] The radius R10 of the volute tongue segment 12 is 13.5mm-14.5mm and the arc length is 27.4mm-28.6mm, the length L15 of the first diffuser straight segment 11 is 28.7mm-29.3mm, and the length L16 of the second diffuser straight segment 17 is 263mm-265mm. A tangent is drawn to the volute tongue segment 12 with the tangent point between the volute tongue segment 12 and the first arc segment 13 as the tangent point, and the angle ∠5 between the tangent and the first diffuser straight segment 11 is 62°-63.5°.

[0086] Preferably, L17 is 290 mm, height L18 is 465 mm, R10 is 14 mm and arc length is 28 mm, L15 is 29 mm, L16 is 264 mm, and ∠5 is 62.78°.

[0087] In this embodiment, a motor 4 and a machine base 5 are further included. The motor 4 is transmission-connected to the impeller 2 via a motor shaft. The volute 1 and the motor 4 are both fixedly arranged on the machine base 5 .

[0088] Through the above technical solution, the arc transition structure of the logarithmic spiral volute 1 profile is adopted to ensure smooth and efficient airflow in the volute 1, reduce the impact and energy loss of the airflow, and thus improve the efficiency of the fan; by optimizing the air outlet 18 and the volute tongue section 12 of the volute 1 to match the outlet airflow angle of the bionic blade, the impact loss and separation of the airflow are reduced, the fan's efficient operating range is broadened, the total pressure and fan efficiency are improved, and the fan noise is further reduced.

[0089] In order to verify this embodiment, based on the preferred structural parameters provided in this embodiment, a centrifugal fan with an impeller having multi-element coupled bionic blades was prepared with an impeller 2 having a diameter of 450 mm (i.e., the diameter of the outer circumference surrounded by the outer ends of all long blades 21 and all short blades 25 of the impeller 2) as a test example for testing. At the same time, a centrifugal fan with a traditional impeller 2 having a diameter of 450 mm and a traditional non-bionic blade was prepared as a comparative example for testing. The test results were converted to atmospheric pressure of 101325 Pa, atmospheric temperature of 20°C, fan speed of 2900 r / min, and medium density of 1.2 kg / m 3 The test data under the test conditions, the test case obtained the test data shown in Table 1 and Figure 9 The performance curve shown in Table 2 is obtained as a comparative example. Figure 10 The performance curve shown is based on volume flow as the horizontal axis. In the performance curve, qvsglGu is the volume flow, LAGu is the A sound level, ηr is the fan efficiency, PrGu is the impeller power, pFGu is the total pressure, and psFGu is the static pressure.

[0090] Table 1

[0091]

[0092] Table 2

[0093]

[0094] From the test data and performance curves, it can be seen that the control ratio is inferior to the test example in terms of volume flow, total pressure, fan efficiency and A sound level. In contrast, the volume flow range of the test example is 3113.5m 3 / h-10802m 3 / h, the optimal fan efficiency is 76.596%, the total pressure is 2225.8Pa, and the A sound level is 86.143dB; the volume flow range of the test case is 3000.5m 3 / h-9110.1m 3 / h, the optimal fan efficiency was 61.281%, the total pressure was 2097.6 Pa, and the A-sound level was 87.597 dB. The test cases generally had higher volume flow, higher total pressure, and higher fan efficiency than the control cases, and the A-sound level of the test cases was generally lower than that of the control cases.

[0095] Compared with the prior art, the present invention provides an impeller and centrifugal fan with multi-coupled bionic blades, based on the principle that the various components in the fan jointly influence the flow, total pressure, efficiency, noise, etc. of the fan in an organically coupled manner. By designing long and short blades with bionic structures and matching and improving the impeller, volute and collector structures, the problems of low flow, low pressure, low efficiency and high noise that are common in centrifugal fans in the prior art are improved.

[0096] In the absence of conflict, the above embodiments and features therein may be combined with each other.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. An impeller with multi-element coupled bionic blades, comprising a front disc and a rear disc, wherein the front disc has an air intake in the middle and the rear disc has a plurality of blades arranged in an array around it, characterized in that: The blades include long blades and short blades that are spaced and evenly distributed, and both the long blades and the short blades are sheet metal single arc multi-coupling bionic blades; The long blade includes a long blade leading edge, a long blade trailing edge, a long blade first side edge connected between first ends of the long blade leading edge and the long blade trailing edge, and a long blade second side edge connected between second ends of the long blade leading edge and the long blade trailing edge, the long blade first side edge being a side edge close to the air suction port, and the long blade second side edge being a side edge away from the air suction port; The leading edge of the long blade includes a leading edge straight line segment, a first leading edge arc segment, a second leading edge arc segment and a third leading edge arc segment that are tangentially connected in sequence, the first leading edge arc segment and the second leading edge arc segment are inscribed inwardly, the second leading edge arc segment and the third leading edge arc segment are circumscribed outwardly, the leading edge straight line segment is connected to the first side edge of the long blade, and the third leading edge arc segment is connected to the second side edge of the long blade; The long blade trailing edge includes a first trailing edge straight segment, a first trailing edge arc segment, a second trailing edge straight segment, a second trailing edge arc segment, a third trailing edge straight segment, a third trailing edge arc segment, a fourth trailing edge arc segment, and a fourth trailing edge straight segment that are sequentially connected. The second trailing edge straight segment, the second trailing edge arc segment, the third trailing edge straight segment, and the third trailing edge arc segment are all sequentially connected and provided with multiple segments. The first trailing edge straight segment is connected to the second side of the long blade, and the fourth trailing edge straight segment is connected to the first side of the long blade. The short blade includes a short blade leading edge, a short blade trailing edge, a short blade first side edge connected between first ends of the short blade leading edge and the short blade trailing edge, and a short blade second side edge connected between second ends of the short blade leading edge and the short blade trailing edge, the short blade first side edge being a side edge close to the air suction port, and the short blade second side edge being a side edge away from the air suction port; The structure of the trailing edge of the short blade is the same as that of the trailing edge of the long blade, and the leading edge of the short blade is perpendicular to the rear disk.

2. The impeller with multi-element coupled bionic blades according to claim 1, characterized in that: In the unfolded view of the long blade, the length L6 of the leading edge straight segment is 11.6 mm to 12.1 mm, the radius R3 of the first arc segment of the leading edge is 44.3 mm to 45.5 mm and the arc length is 70 mm to 71.2 mm, the radius R4 of the second arc segment of the leading edge is 36.8 mm to 37.2 mm and the arc length is 9 mm to 9.5 mm, and the radius R5 of the third arc segment of the leading edge is 199 mm to 201 mm and the arc length is 104 mm to 107 mm; The length L7 of the first straight line segment of the trailing edge is equal to that of the fourth straight line segment of the trailing edge and is 9 mm to 9.2 mm. The radius R6 of the first arc segment of the trailing edge and the fourth arc segment of the trailing edge are equal to each other and are 1.75 mm to 2.25 mm, and the arc length is equal to each other and is 2.4 mm to 2.6 mm. The length L8 of the second straight line segment of the trailing edge and the length L9 of the third straight line segment of the trailing edge are equal to each other and are 8.7 mm to 8.9 mm. The radius R7 of the second arc segment of the trailing edge is 1.75 mm to 2.25 mm, and the arc length is 5.15 mm to 5.45 mm. The radius R8 of the third arc segment of the trailing edge is 1.1 mm to 1.4 mm, and the arc length is 3.2 mm to 3.4 mm. The distance L10 between the centers of adjacent second arc segments of the trailing edge is 10.4 mm to 10.6 mm, and the distance L11 between the centers of adjacent third arc segments of the trailing edge is 10.4 mm to 10.6 mm. The length L12 of the second side of the long blade is 195mm-198mm; In the unfolded view of the short blade, the length L3 of the leading edge of the short blade is 123.6 mm-124.5 mm, and the length L5 of the second side of the short blade is 71 mm-72 mm.

3. The impeller with multi-element coupled bionic blades according to claim 2, characterized in that: The front disc is set to an arc structure, the vertical distance L2 between the air intake and the rear disc is 184mm-186mm, and the vertical distance L4 between the end of the front disc away from the air intake and the rear disc is 114.5mm-115.5mm; The impeller is cut with a plane passing through the central axis of the impeller. The radius R2 of the arc surface of the front disk in the cross section is 80.4mm-81.5mm and the arc length is 117mm-118mm. The inlet angle ∠1 when the long blade is installed is 23.5°-24.5°, the inlet angle ∠2 when the short blade is installed is 29.5°-30.5°, the outlet angle ∠3 when the long blade is installed is equal to the outlet angle ∠4 when the short blade is installed and is 27.5°-28°. On the projection surface of the rear disc, the radius R1 of the arc surface of the long blade is 206mm-208mm and the arc length is 194mm-196.4mm, and the radius R15 of the arc surface of the short blade is 206mm-208mm and the arc length is 70mm-72mm; The diameter φ1 of the outer circle formed by the outer ends of all long blades and all short blades of the impeller is 450mm, the diameter φ2 of the inner circle formed by the inner ends of all long blades is 259mm-261mm, and the diameter φ3 of the inner circle formed by the inner ends of all short blades is 399mm-381mm; With the impeller's rotation direction as the front, the distance L1 between the outermost end of the long blade and the outermost end of the adjacent short blade behind is 65.8mm-66.2mm; The diameter φ4 of the air suction port is 292mm-294mm, and 8 long blades and 8 short blades are provided.

4. The impeller with multi-element coupled bionic blades according to claim 3, characterized in that: L6 is 11.9mm, R3 is 45mm and the arc length is 70.7mm, R4 is 37mm and the arc length is 9.3mm, R5 is 200mm and the arc length is 105.5mm, L7 is 9.1mm, R6 is 2mm and the arc length is 2.5mm, L8 is 8.8mm, R7 is 2mm and the arc length is 5.3mm, R8 is 1.25mm and the arc length is 3.3mm, L10 is 10.5mm, L11 is 10.5mm, L12 is 196.6mm, and L3 is 124.1m m, L5 is 71.5mm, L2 is 185mm, L4 is 115mm, R2 is 81mm and the arc length is 117.49mm, ∠1 is 23.93°, ∠2 is 30.01°, ∠3 is 27.8°, the radius R1 of the arc surface of the long blade is 207mm and the arc length is 195.17mm, the radius R15 of the arc surface of the short blade is 207mm and the arc length is 70.95mm, φ2 is 260mm, φ3 is 380mm, L1 is 66.03mm, and φ4 is 293mm.

5. A centrifugal fan comprising a volute and a flow collector fixedly disposed in the volute, characterized in that: It also includes the impeller according to any one of claims 1 to 4, the impeller is arranged in the volute, a radial gap is provided between the impeller and the collector, and the width L19 of the radial gap is 4.8 mm to 5.2 mm.

6. A centrifugal fan according to claim 5, characterized in that: The collector includes a connecting portion, an air guide portion, an air inlet and an air guide port. The air guide portion is fixedly connected to the volute through the connecting portion. The connecting portion is annular and the inner periphery forms the air inlet. The outlet of the air guide portion forms the air guide port. The collector is cut with a plane passing through the central axis of the collector. In the cross section, the air guide portion is set to a single arc structure. The radius R9 of the arc surface of the air guide portion is 76mm-78mm and the arc length is 145mm-148mm. From the air inlet to the air guide, the diameter of the air guide portion is configured to gradually decrease and then gradually expand in the direction away from the air inlet. The diameter φ7 of the narrowest part of the air guide portion is 276mm-277mm. The diameter φ5 of the air inlet is 424.5mm-427.5mm, the diameter φ6 of the air guide outlet is 283mm-285mm, the vertical distance L13 between the narrowest part of the air guide part and the air inlet is 76mm-77mm, and the vertical distance L14 between the narrowest part of the air guide part and the air guide outlet is 24mm-24.4mm.

7. A centrifugal fan according to claim 6, characterized in that: R9 is 77mm and the arc length is 146.65mm, φ7 is 276.38mm, φ5 is 426mm, φ6 is 284.21mm, L13 is 76.48mm, and L14 is 24.16mm.

8. The centrifugal fan according to claim 7, characterized in that: The profile of the volute includes a first diffuser straight segment, a volute tongue segment, a first arc segment, a second arc segment, a third arc segment, a fourth arc segment, and a second diffuser straight segment, which are sequentially connected tangentially; the first diffuser straight segment and the second diffuser straight segment enclose an air outlet, and the first arc segment, the second arc segment, the third arc segment, and the fourth arc segment are not cocentric; A rectangular coordinate system is established with the center of the impeller as the coordinate origin. When the first diffuser straight segment is located in the third quadrant, the coordinates of the center O2 of the first arc segment are (-21, 39), the radius R11 is 249mm-253mm, and the arc length is 149mm-151mm. The coordinates of the center O1 of the second arc segment are (57, 39), the radius R12 is 326mm-330mm, and the arc length is 483mm-487mm. The coordinates of the center O4 of the third arc segment are (57, -57), the radius R13 is 422mm-428mm, and the arc length is 664mm-670mm. The coordinates of the center O3 of the fourth arc segment are (-21, -57), the radius R14 is 500mm-506mm, and the arc length is 785mm-795mm. Both the first diffuser straight segment and the second diffuser straight segment are arranged perpendicular to the air outlet.

9. The centrifugal fan according to claim 8, characterized in that: The width L17 of the air outlet is 288mm-292mm, and the height L18 is 462mm-468mm; The radius R10 of the volute tongue segment is 13.5mm-14.5mm and the arc length is 27.4mm-28.6mm. The length L15 of the first diffuser straight segment is 28.7mm-29.3mm. The length L16 of the second diffuser straight segment is 263mm-265mm. The tangent line of the volute tongue segment is drawn with the tangent point of the volute tongue segment and the first arc segment as the tangent point. The angle ∠5 between the tangent line and the first diffuser straight segment is 62°-63.5°.

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