CN111894872A

CN111894872A - Two-stage booster-type low noise fan

Info

Publication number: CN111894872A
Application number: CN202010660425.0A
Authority: CN
Inventors: 李诗徉; 蒋洪涛; 叶豪杰
Original assignee: Shaoxing Zhixin Electromechanical Technology Co ltd
Current assignee: Hangzhou Zhixin Electromechanical Design Co., Ltd.
Priority date: 2020-07-10
Filing date: 2020-07-10
Publication date: 2020-11-06

Abstract

The invention provides a two-stage booster-type low-noise fan, and belongs to the field of low-noise pneumatic design. The two-stage supercharging low-noise fan is characterized by comprising a shell, wherein the shell is provided with an air inlet and an air outlet, a rotating structure is arranged in the shell and comprises a mixed flow type one-stage impeller and a centrifugal type two-stage impeller, a one-stage guide vane used for guiding airflow is arranged between the one-stage impeller and the two-stage impeller, a driving device used for driving the rotating structure to rotate is arranged inside the one-stage guide vane, the shell comprises a volute arranged outside the two-stage impeller, and the air outlet is arranged on the volute. The invention has the advantages of low noise and the like.

Description

Two-stage booster-type low noise fan

Technical Field

The invention belongs to the field of low-noise pneumatic design, and particularly relates to a two-stage booster type low-noise fan.

Background

The application scenes of the fans on ships are very wide, and fans which need to axially enter and radially flow out are arranged; axial entry, axial exit fans are also required. The existing fan on the ship mostly adopts a single-stage booster fan, the fan can generate great noise when in operation, and the noise and vibration level of the fan are directly related to the concealment of the ship when in navigation. In order to reduce noise, various methods are devised, for example, a low-frequency vibration isolation device, a double-layer vibration isolation device, and the like are adopted, and noise can be reduced by starting with the design of the fan itself. However, compared with the improvement of performance and efficiency, the difficulty of reducing the fan noise is much greater, and even in some fan optimization cases, the aerodynamic efficiency is obviously improved, but the noise level is not changed. When the fan is designed, the full pressure and the flow of the fan are unchanged, so that the noise of the fan is reduced in a crucial way under the condition that the full pressure and the flow of the fan are unchanged.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provides a two-stage booster type low-noise fan.

The purpose of the invention can be realized by the following technical scheme: the utility model provides a two-stage booster-type low noise fan, a serial communication port, which comprises an outer shell, the shell be provided with air intake and air outlet, the shell in be provided with rotating-structure, rotating-structure include mixed flow one-level impeller and centrifugal second grade impeller, one-level impeller and second grade impeller between be provided with the one-level stator that is used for leading the air current, the inside drive arrangement who is used for driving rotating-structure rotation that is provided with of one-level stator, the shell including locating the outer spiral case of second grade impeller, the air outlet locate on the spiral case.

The working principle of the invention is as follows: when the volute casing works, air enters from the air inlet, sequentially passes through the primary impeller, the primary guide vane and the secondary impeller, and finally flows out from the air outlet on the volute casing. The invention adopts the structural forms of a primary mixed-flow impeller and a secondary centrifugal impeller, namely, the primary impeller is a mixed-flow impeller, the secondary impeller is a centrifugal impeller, a primary guide vane is adopted in the middle of the two-stage impeller for flow guiding, a driving device is arranged in the primary guide vane, and the outlet of the secondary impeller is guided in a volute form, so that the mechanical noise of a shielding driving device can be effectively reduced, the absolute wind speed in the fan can be effectively reduced, the pneumatic noise can be greatly reduced, meanwhile, the structural form can also realize the requirements of axial air inlet and radial air outlet, and the whole structure of the fan is compact.

Preferably, the primary impeller comprises a first wheel disc and first blades uniformly arranged along the circumferential direction of the first wheel disc, the driving device is partially positioned in the first wheel disc, and the driving device is rotatably connected with the first wheel disc through a first rotating shaft.

Preferably, the ratio of the suction diameter of the first vane to the outer diameter of the first vane is between 0.1 and 0.9, the working face exit angle of the first vane is between 10 ° and 90 °, the back face exit angle of the first vane is between 10 ° and 90 °, and the wrap angle of the first vane is between 0 ° and 150 °.

Preferably, the secondary impeller comprises a second wheel disc and second blades uniformly arranged along the circumferential direction of the second wheel disc, and the driving device is rotatably connected with the second wheel disc through a second rotating shaft.

Preferably, the ratio of the suction diameter of the second blade to the outer diameter of the second blade is between 0.3 and 0.9, the working face outlet angle of the second blade is between 10 and 60 degrees, the back face outlet angle of the second blade is between 20 and 90 degrees, and the wrap angle of the second blade is between 0 and 150 degrees.

Preferably, one-level stator including leading the bladed disk and along the stator blade that leads the circumferential direction of bladed disk and evenly set up, drive arrangement part be located leading the bladed disk, drive arrangement be provided with the installed part, the inside of leading the bladed disk be provided with the fixed part, the installed part pass through first connecting piece and fixed part and connect, the installed part evenly be provided with the air current hole along the circumferential direction, lead between bladed disk and first rim plate and the second rim plate all have the clearance. In the operation process of the fan, the front end surface and the rear end surface of the first-stage guide vane generate pressure difference, so that air around the driving device flows, and the driving device is taken away to generate heat, thereby achieving the purpose of cooling.

Preferably, the first blade and the second blade are both integers greater than 1; the number of the guide vane blades and the number of the first blades or the second blades are relatively prime.

Preferably, the ratio of the suction diameter of the guide vane blade to the outer diameter of the guide vane blade is 1.1-3, the working face outlet angle of the guide vane blade is 120-170 degrees, the back face outlet angle of the guide vane blade is 60-130 degrees, and the wrap angle of the guide vane blade is 0-150 degrees. The first-stage guide vane is in a space guide vane form and converts the speed circulation of wind into the pressure potential energy of the wind.

Preferably, one-level stator still include with stator blade one side fixed connection's first casing, the shell including locating the outer first shell of one-level impeller, first shell, first casing, spiral case loop through the second connecting piece can dismantle the connection. The guide vane blade not only plays a role in guiding airflow, but also plays a role in reinforcing ribs.

Preferably, the first casing is provided with a base corresponding to the position of the first-stage guide vane. The purpose of setting up the frame is in order to reduce vibration, noise reduction.

Compared with the prior art, the invention has the following advantages:

1. the invention adopts the structural forms of a primary mixed-flow impeller and a secondary centrifugal impeller, namely, the primary impeller is a mixed-flow impeller, the secondary impeller is a centrifugal impeller, a primary guide vane is adopted in the middle of the two-stage impeller for flow guiding, a driving device is arranged in the primary guide vane, and the outlet of the secondary impeller is guided in a volute form, so that the mechanical noise of a shielding driving device can be effectively reduced, the absolute wind speed in the fan can be effectively reduced, the pneumatic noise can be greatly reduced, meanwhile, the structural form can also realize the requirements of axial air inlet and radial air outlet, and the whole structure of the fan is compact.

Drawings

FIG. 1 is a schematic cross-sectional view of the present invention;

FIG. 2 is a schematic structural view of the mount of the present invention;

FIG. 3 is a schematic view of the left side of the present invention;

FIG. 4 is a right side schematic view of an embodiment of the present invention;

FIG. 5 is a schematic view of the outlet of the present invention;

fig. 6 is a schematic view of the structure of the airflow holes of the present invention.

In the figure, 1, a housing; 101. a first housing; 111. an air inlet; 102. a volute; 112. an air outlet; 2. a rotating structure; 201. a first-stage impeller; 211. a first wheel disc; 221. a first blade; 202. a secondary impeller; 212. a second wheel disc; 222. a second blade; 3. a first stage guide vane; 301. a guide vane disk; 311. a fixed part; 302. a guide vane blade; 303. a first housing; 4. a drive device; 401. a first rotating shaft; 402. a second rotating shaft; 403. a mounting member; 413. an airflow aperture; 5. a gap; 6. a first connecting member; 7. a second connecting member; 8. a machine base; 801. a base; 802. a machine arm.

Detailed Description

The following is a detailed embodiment of the present invention and the accompanying drawings are incorporated to illustrate the technical solution of the present invention

Further, the present invention is not limited to these examples.

As shown in fig. 1 to 6, a two-stage booster type low noise fan includes a housing 1, the housing 1 includes a volute 102 and a first housing 101, the housing 1 is provided with an air outlet 112 and an air inlet 111, the air outlet 112 is located on the volute 102, and the air inlet 111 is located on the first housing 101. A rotating structure 2 is arranged in the housing 1, and the rotating structure 2 comprises a first-stage impeller 201 and a second-stage impeller 202. A first-stage guide vane 3 is arranged between the first-stage impeller 201 and the second-stage impeller 202, a driving device 4 is arranged inside the first-stage guide vane 3, and the driving device 4 can drive the rotating structure 2 to rotate. The first-stage guide vane 3 is also provided with a base 8. Wind enters from the wind inlet 111, sequentially passes through the primary impeller 201, the primary guide vane 3 and the secondary impeller 202, and then flows out from the wind outlet 112 on the volute 102. Air enters axially from the primary impeller 201 and exits radially from the secondary impeller 202.

In further detail, the first-stage impeller 201 is a mixed-flow impeller, the first-stage impeller 201 includes a first disk 211 and a first blade 221, the first blade 221 is fixedly connected with the first disk 211, and the first blade 221 is uniformly arranged along the circumferential direction of the first disk 211. The air is pressurized in a first stage and enters the first stage guide vanes 3.

In more detail, the secondary impeller 202 is a centrifugal impeller, the secondary impeller 202 includes a second disk 212 and a second blade 222, the second blade 222 is fixedly connected to the second disk 212, and the second blade 222 is uniformly arranged along the circumferential direction of the second disk 212. The air is pressurized in two stages, and wind energy flows out radially.

The first-stage impeller 201 and the second-stage impeller 202 both adopt a closed impeller mode, and are high in structural strength, convenient to process and not easy to deform.

Further saying, one-level stator 3 includes stator blade disc 301 and stator blade 302, stator blade 302 one side and stator blade disc 301 fixed connection, stator blade 302 opposite side fixedly connected with first casing 303, stator blade 302 is located between inside stator blade disc 301 and the first casing 303 in the outside promptly, one-level stator 3 adopts closed blade mode equally, stator blade 302 has not only played the effect of air current direction, has played the effect of strengthening rib simultaneously for one-level stator 3's structural strength is high.

In more detail, the driving device 4 is a double-output shaft motor, and the driving device 4 is connected with the first wheel disc 211 through a first rotating shaft 401 to drive the first-stage impeller 201 to rotate; the driving device 4 is connected to the second disk 212 via a second rotating shaft 402, and drives the secondary impeller 202 to rotate. The driving device 4 is located inside the first wheel disc 211 and the guide vane disc 301, so that mechanical noise of the motor can be effectively reduced, and the first wheel disc 211 and the guide vane disc 301 play a role in shielding mechanical noise of the motor. The driving device 4 is provided with a mounting part 403, in this embodiment, the mounting part 403 is a flange, a fixing part 311 is arranged inside the guide vane disc 301, the flange is connected with the fixing part 311 through a first connecting part 6, in this embodiment, the first connecting part 6 is a bolt, a plurality of airflow holes 413 are arranged along the circumferential direction of the flange, and a gap 5 exists between the guide vane disc 301 and the first and

second wheel discs

211 and 212. In the operation process of the fan, the front end surface and the rear end surface of the first-stage guide vane 3 generate pressure difference, and wind mainly enters from the air inlet 111, sequentially passes through the first-stage impeller 201, the first-stage guide vane 3 and the second-stage impeller 202, and then flows out from the air outlet 112 on the volute 102. However, due to the pressure difference between the front end face and the rear end face of the first-stage guide vane 3, a small part of wind enters the guide vane disc 301 from the gap 5 between the guide vane disc 301 and the second wheel disc 212, then flows out of the guide vane disc 301 from the gap 5 between the guide vane disc 301 and the first wheel disc 211 through the airflow holes 413, so that the surface of the driving device 4 forms a micro-circulation, as shown by the arrow direction in fig. 2, the heat on the surface of the driving device 4 is taken away, and the purpose of cooling is achieved. The motor of the invention does not need to be provided with a fan, the running of the fan can generate noise, and the motor of the invention cancels the arrangement of the fan, thereby reducing the noise.

In more detail, a base 8 corresponding to the position of the first stage guide vane 3 is arranged outside the first casing 303. The base 8 comprises a base 801 and machine arms 802 positioned on two sides of the base 801, the machine arms 802 are fixed on two sides of the first shell 303 and fixedly connected through bolts, and the base 8 is fixed on the ground through bolts, so that vibration and noise are reduced. Because the motor can vibrate during operation, the motor and the guide vane disc 301 are firmly fixed through the flange and the fixing part 311, and then the fan is fixed on the ground through the base 8, so that the overall vibration of the fan is reduced, and the noise is reduced.

In further detail, the first housing 1011, the first housing 303, and the volute 102 are detachably connected in sequence by the second connecting member 7. In this embodiment, the second connecting member 7 is a bolt. The first housing 1011, the first housing 303, and the scroll 102 of the present invention are detachable from each other. The first-stage impeller 201, the first-stage guide vane 3, the second-stage impeller 202, the first outer shell 1011, the volute 102, the driving device 4 and the base 8 can be mutually detached and can enter a door with the diameter of 600 mm. The whole focus of fan is in the motor position, and the center pin of shell 1, the center pin of revolution mechanic 2, the center pin of one-level stator 3, the center pin of motor all coincide. A convenient hoisting hanger can be designed on the gravity center vertical line. Iron cores are pre-embedded at the assembly positions of the first-stage impeller 201 and the second-stage impeller 202 and the motor.

When the fan is designed, the total full pressure and the total flow of the fan are not changed, and under the condition that the full pressure and the total flow of the fan are not changed, the two-stage booster fan has lower noise than the existing single-stage booster fan. Because all the flow rates are the same, for example, Q, the total pressure of the fan is Pt. The invention adopts two stages of impellers, the flow of each stage of impeller is still Q, but the full pressure shared by each stage of impeller is smaller than the total full pressure, so that the peripheral speed of each stage of impeller is reduced, and the diameter of each stage of impeller is also reduced. Therefore, the fan adopting the two-stage impeller can effectively reduce the absolute speed inside the fan, thereby reducing the noise of the fan. And the diameter of the impeller blades of each stage is reduced. Therefore, the invention adopts the structural form of the primary mixed-flow impeller and the secondary centrifugal impeller, can effectively reduce the absolute wind speed in the fan, thereby greatly reducing the aerodynamic noise, and the structural form can also realize the requirements of axial air inlet and radial air outlet.

Under the condition of ensuring the pneumatic efficiency, in order to greatly reduce the pneumatic noise, the parameters of the fan provided by the invention need to meet the following conditions:

the full pressure ratio shared by the first-stage impeller 201 and the second-stage impeller 202 is 0.8: 1-1.2: 1, one-level stator 3 adopts the form of space stator, and one-level stator 3 ring face diameter is along axial convergent from the entry to the export promptly, and one-level stator 3 entry flows to the area and flows to the area with the export and be 0.9: 1-1.1: 1, the inlet area of the second-stage impeller 202 is consistent with the outlet area of the first-stage guide vane 3, and the number of blades of the first-stage impeller 201 and the second-stage impeller 202 is an integer greater than 1; that is, the first blade 221 and the second blade 222 are both integers greater than 1. The number of blades of the first-stage guide vane 3 is greater than the number of blades of the first-stage impeller 201 or the second-stage impeller 202, and the value of the number of blades of the first-stage guide vane 3 is coprime to the number of blades of the first-stage impeller 201 or the second-stage impeller 202, that is, the number of guide vane blades 302 is greater than the number of first blades 221 or second blades 222, and coprime to the number of first blades 221 or second blades 222.

The distance from the front edge of the flow surface in the middle of the blade to the center of the impeller is called as the suction diameter of the blade D1, the distance from the tail edge of the flow surface in the middle of the blade to the center of the impeller is called as the outer diameter D2 of the long blade, the blade setting angle of the working surface of the blade is the included angle between the tangent of the convex surface of the blade and the circumferential direction, the blade setting angle of the back surface of the blade is the included angle between the tangent of the concave surface of the blade and the circumferential direction, the blade setting angle at the inner diameter of the blade is the inlet angle of the blade. The working surface outlet angle of the blade is beta 1, the back surface outlet angle is beta 2, and the wrap angle of the blade is theta;

first blade 221 parameters of the mixed-flow primary impeller 201: d1 is more than or equal to 0.1, D2 is more than or equal to 0.9, beta 1 is more than or equal to 10 degrees and less than or equal to 90 degrees, beta 2 is more than or equal to 10 degrees and less than or equal to 90 degrees, and theta is more than or equal to 0 degrees and less than or equal to 150 degrees.

Guide vane blade 302 parameters of the first stage guide vane 3: d1 is more than or equal to 1.1, D2 is less than or equal to 3, beta 1 is more than or equal to 120 degrees and less than or equal to 170 degrees, beta 2 is more than or equal to 60 degrees and less than or equal to 130 degrees, and theta is more than or equal to 0 degrees and less than or equal to 150 degrees.

Second blade 222 parameters of the centrifugal two-stage impeller 202: d1 is more than or equal to 0.3, D2 is more than or equal to 0.9, beta 1 is more than or equal to 10 degrees and less than or equal to 60 degrees, beta 2 is more than or equal to 20 degrees and less than or equal to 90 degrees, and theta is more than or equal to 0 degrees and less than or equal to 150 degrees.

Example 1

The full pressure ratio shared by the first-stage impeller 201 and the second-stage impeller 202 is 1: 1, the inlet flow area and the outlet flow area of the first-stage guide vane 3 are 1: 1.

first blade 221 parameters of the mixed-flow primary impeller 201: a number of 11 tablets, D1=270mm, D2=470mm, β 1=25 °, β 2=30 °, θ =83 °.

Guide vane blade 302 parameters of the first stage guide vane 3: a number of 13 tablets, D1=500mm, D2=240mm, β 1=150 °, β 2=85 °, θ =40 °;

second blade 222 parameters of the centrifugal two-stage impeller 202: a number of 11 pieces, D1=310mm, D2=470mm, β 1=15 °, β 2=30 °, θ =40 °.

The decibel noise of example 2 was measured to be 69 decibels.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Although terms are used more often herein, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.

Claims

1. The utility model provides a two-stage booster-type low noise fan, its characterized in that, includes shell (1), shell (1) be provided with air intake (111) and air outlet (112), shell (1) in be provided with rotating-structure (2), rotating-structure (2) including mixed flow formula one-level impeller (201) and centrifugal second grade impeller (202), one-level impeller (201) and second grade impeller (202) between be provided with one-level stator (3) that are used for leading the air current, one-level stator (3) inside be provided with be used for driving rotating-structure (2) rotatory drive arrangement (4), shell (1) including locating outer spiral case (102) of second grade impeller (202), air outlet (112) locate on spiral case (102).

2. A two-stage supercharging type low-noise blower according to claim 1, wherein the one-stage impeller (201) includes a first disk (211) and first blades (221) uniformly arranged along a circumferential direction of the first disk (211), the driving device (4) is partially located in the first disk (211), and the driving device (4) and the first disk (211) are rotatably connected through a first rotating shaft (401).

3. A two-stage supercharging low-noise blower according to claim 2, characterized in that the ratio of the suction diameter of the first blade (221) to the outer diameter of the first blade (221) is between 0.1 and 0.9, the working face exit angle of the first blade (221) is between 10 ° and 90 °, the back face exit angle of the first blade (221) is between 10 ° and 90 °, and the wrap angle of the first blade (221) is between 0 ° and 150 °.

4. A two-stage supercharging type low-noise blower according to claim 2, wherein the secondary impeller (202) comprises a second disk (212) and second blades (222) uniformly arranged along the circumferential direction of the second disk (212), and the driving device (4) and the second disk (212) are rotatably connected through a second rotating shaft (402).

5. A two-stage supercharging low-noise blower according to claim 4, characterized in that the ratio of the suction diameter of the second blade (222) to the outer diameter of the second blade (222) is between 0.3 and 0.9, the working face exit angle of the second blade (222) is between 10 ° and 60 °, the back face exit angle of the second blade (222) is between 20 ° and 90 °, and the wrap angle of the second blade (222) is between 0 ° and 150 °.

6. A two-stage supercharging low-noise fan according to claim 4, characterized in that the first stage guide vane (3) includes a guide vane disk (301) and guide vane blades (302) uniformly arranged along the circumferential direction of the guide vane disk (301), the driving device (4) is partially located in the guide vane disk (301), the driving device (4) is provided with a mounting member (403), a fixing portion (311) is arranged inside the guide vane disk (301), the mounting member (403) is connected with the fixing portion (311) through a first connecting member (6), the mounting member (403) is uniformly provided with air flow holes (413) along the circumferential direction, and a gap (5) exists between the guide vane disk (301) and the first and second rotary disks (211, 212).

7. A two-stage supercharging low-noise blower according to claim 6, characterized in that the first blade (221) and the second blade (222) are both integers greater than 1; the number of the guide vane blades (302) is coprime to the number of the first blades (221) or the second blades (222).

8. A two-stage supercharged low-noise fan according to claim 6, characterized in that the ratio of the suction diameter of the guide vane blade (302) to the outer diameter of the guide vane blade (302) is between 1.1 and 3, the working face exit angle of the guide vane blade (302) is between 120 ° and 170 °, the back face exit angle of the guide vane blade (302) is between 60 ° and 130 °, and the wrap angle of the guide vane blade (302) is between 0 ° and 150 °.

9. The two-stage supercharging type low-noise fan according to claim 6, wherein the one-stage guide vane (3) further comprises a first casing (303) fixedly connected with one side of the guide vane blade (302), the casing (1) comprises a first casing (101) arranged outside the one-stage impeller (201), and the first casing (101), the first casing (303) and the volute (102) are detachably connected through a second connecting piece (7) in sequence.

10. A two-stage booster-type low noise blower according to claim 6, characterized in that the first casing (303) is provided with a seat (8) corresponding to the position of the one-stage guide vane (3).