UA23005U - Tube axial fan fan - Google Patents

Abstract

A tube axial fan has a cylindrical housing, inlet collector, back cowl, working wheel, this is kinematically connected to engine, formed with main and cover disc and bended back paddles placed between discs, inlet collector symmetrical with respect to axle, this is placed as one of ends of the housing, it is arranged with curvilinear profile in diameter cross-section with formation of confuser gap between surfaces of cover disc and inlet collector, at that axis of rotation of working wheel is arranged coaxially with respect to axis of symmetry of inlet collector, between inlet collector and cover disc swirl chamber is formed, and between walls of the housing -channel. Besides that, it has paddle rectification apparatus, this is placed behind main disc of working wheel, cross-section area of the channel is not less than 2,4 of area of circle described by the ends of paddles of working wheel, back cowl is arranged with account of conical form and connected to the walls of the channel by paddles of directing apparatus.

Description

Description of the invention

The useful model refers to ventilation equipment, namely, to channel fans with a radial 2 impeller.

Channel fans with a radial impeller are known from the state of the art. Thus, from the description of the invention to the US patent Mo5810557, IPC RO4O 17/08, IPC 415/206, publication date 09/22/98, (1), a duct fan is known, which contains a cylindrical body, an inlet manifold, a rear fairing, an impeller, kinematically connected to the engine, which is formed by the main and cover discs and vanes bent back 70 degrees located between the discs, an axially symmetrical inlet manifold located on one of the ends of the housing, made with a curvilinear profile in the diametrical section with the formation of a confusing gap between the surfaces of the cover disc and inlet manifold, while the axis of rotation of the impeller is aligned with the axis of symmetry of the inlet manifold, a vortex cavity is formed between the inlet manifold and the cover disk, and a channel is formed between the walls of the housing. The disadvantage of the invention |1|, which is considered to be the closest analog of the invention 72, is the large dimensions of the cross-section of the channel, which makes it difficult to use the fan in systems with air ducts with a large aspect ratio and with limited height dimensions.

The technical problem to be solved is to create a channel fan with a small ratio of the diameters of the channel and the impeller.

The technical result consists in increasing the coefficient of total pressure in the duct fan with the same value of the coefficient of performance.

A channel fan, like the closest analogue |1), contains a cylindrical body, an inlet manifold, a rear fairing, an impeller kinematically connected to the engine, which is formed by the main and cover disks and blades bent back between the disks, symmetrical relative to the input axis the collector, located on one of the ends of the housing, is made with a curvilinear profile in the diametrical section with the formation of a confusing gap between the surfaces of the cover disk and the inlet collector, while the axis of rotation of the impeller is made coaxial with the axis of symmetry of the inlet collector, between the inlet collector and the cover disk a vortex cavity is formed, and a channel is formed between the walls of the case, but unlike the closest analogue |1|, the fan has a blade straightening device, which is located behind the main disk of the impeller, the area, and the cross section of the channel is at least 2.4 of the circle area , which describe the ends of the blades of the impeller, the rear fairing is made of a part with a conical shape and connected to it by the walls of the channel and the blades of the straightening device.

The channel fan is characterized by the fact that vortex dampers are installed in the vortex cavity. at

At the same time, vortex suppressors are made in the form of a straightening device, which contains at least one plate located in the vortex cavity. 3o In addition, at least one plate of the vortex damper is connected to the wall of the channel and the inlet collector. high school

The channel fan is characterized by the fact that the engine is located in the rear fairing and is connected to the impeller by means of the hub, which is located on the main disk.

At the same time, the fairing is equipped with a front wall, in which at least one hole is made for cooling /"F, the engine, the section of the fairing in which the engine is located is made of a cylindrical shape, and the conical section C 50 is adjacent to the cylindrical one, the rear end of the conical section can be equipped with a plug . c In addition, the fan is equipped with a pipe for engine ventilation, which is pneumatically connected to the fairing,

And the rear end of the conical section is equipped with a plug.

The channel fan is characterized by the fact that the blades of the straightening device are made with a length of 0.4-0.5 of the diameter of the impeller.

At the same time, the front edge of the blades of the straightening device is located in front of the edge of the main disk at a distance of 0.1-0.3 of the width of the impeller blades. оз In addition, the front section of the vane of the steering device is made in the form of an arc, the free edge of which is located at an angle of no more than 452 to the axis of rotation of the impeller in the direction of its rotation. o The channel fan is characterized by the fact that the blades of the impeller are flat. (in 50 At the same time, the generating area of the curvilinear cover disc in the area of attachment of the impeller blades is made in accordance with the equations: sl y-(0.29-0.01)x0.37 2-(-0.39--0.01)x -0.27, ря ххгну? where: 2-2/О0 - relative coordinate directed along the axis of rotation of the impeller in the direction from the main disk to the entrance to the impeller; хАХ/О - relative coordinate perpendicular to the axis of rotation of the impeller wheels; umo - relative coordinate, perpendicular to axis 2 and axis x; in g - R/O - relative radius of the impeller,

K - the current radius of the impeller;

X, Y, 2 - current coordinates; p - the diameter of the impeller.

The channel fan is characterized by the fact that a screen is installed in the channel of the housing, which is connected to the DB / Housing with the formation of a cavity between the screen, the housing and the suction nozzle, while the edge of the screen is located at a distance of 0.01-0.10 of the width of the impeller blades from the cover disc in the direction of the main disk and stand back from the specified blades no closer than 0.01 of the diameter of the impeller.

The channel fan is characterized by the fact that the housing includes connected front and rear parts, while in the front part there is an inlet manifold and an impeller connected to the engine, and in the rear part there is a fairing connected to the walls of the housing by means of the blades of the straightening device.

The channel fan is characterized by the fact that the main disk of the impeller is made with ventilation holes.

A useful model is explained with drawings.

Figure 1 shows a longitudinal section of a channel fan. 70 Fig. 2 shows a longitudinal section of a channel fan with a screen.

Fig. 3 shows a longitudinal section of a channel fan with engine cooling.

Fig. 4 shows the section A-A in Fig. 1, 2.

Fig. 5 shows a section B-B in Fig. 3.

Fig. 6 shows the remote element B in Fig. 1, 3.

Fig. 7 shows the remote element G in Fig. 3.

Fig. 8 shows the remote element D in Fig. 2.

Figure 9 shows the dependence of the static pressure coefficient mu on the relative area 5/5rK at constant values of the productivity coefficient f.

Fig. 10 shows the dependence of the coefficient of static pressure лу on the coefficient of performance ф for different versions of the eddy damper plates.

Fig. 11 shows the dependence of the static noise pressure coefficient on the performance coefficient "r" of the proposed fan and the closest analogue.

The channel fan includes a housing 1, an engine 2, an impeller 3, an inlet manifold 4, a straightening device 5 and a rear fairing 6 (Fig. 1, 2, 3).

The body 1 is made with a vortex cavity 7, which is located between the inlet manifold 4, the impeller 7

With, and channel 8, which has a cylindrical shape with a base in the form of a circle. For connection with air ducts and ventilation equipment (not shown in Fig.), connecting flanges 9 are attached to the ends of the housing 1 (Fig. 1,

Z, 7). Panels (not shown in Fig.) containing heat-insulating and/or sound-absorbing material can be installed on the walls of the housing 1. IF)

The impeller C contains the cover (or front) 10 and the main (or rear) 11 discs, the vanes 12 (Fig. 1, 2, 3) are located between them, bent back in the direction of rotation of the wheel C (Fig. 4), and kinematically connected to the engine 2, for example, by means of the hub 13, which is fixed on the main disk 11 and connected to the shaft 14 (a) of the engine 2 (Fig. 7) by a belt, etc. transmission (not shown in Fig.). The axis 15 of rotation of the impeller Z c is located along the channel 8 and, as a rule, coincides with the axis of symmetry of the input collector 4 or is parallel to it. The housing 1 is made in such a way that in the plane that is perpendicular to the axis of symmetry of the inlet collector 4 in the place of installation of the impeller Z (Fig. 1-4) the ratio of the area 5 of the cross section of the channel 8 (between the walls of the housing 1) to the area Zrk-rOGA of the working wheels Z (corresponding to the area bounded by the circle of the maximum diameter 0, which is described by the ends of the blades 12) is at least 2.4: 5/Zrk"2 4. "

The inlet collector 4, which is located at the end of the housing 1, is symmetrical about the axis and has a curvilinear profile in the diametrical section with the formation of a confusing gap 16 between the surfaces C of the cover disk 10 and the inlet collector 4 (Fig. b). "» The straightening device 5 has vanes 17, the front edge of which can be located between the main 11 and "covering 10 disks with the input part, which is made in the form of an arc located at an angle of 409-459 to the axis of rotation 15 of the impeller Z (Fig. 7).

The rear fairing 6 includes a cylindrical 18 and/or conical 19 section. The rear fairing 6 can be connected to the body 1 by means of blades 17 of the straightening device 5 (Fig. 4, 5), or other elements (in Fig. no

Ge) is shown). A wall 20 can be installed in the front end of the rear fairing, and a plug 21 in the rear end (Fig. 1, 3). The wall 20 is made with holes 22 for cooling the engine with air passing through the fan (Fig. 5)3. The cavity of the rear fairing b can be connected to the atmosphere by means of 20 air duct (pipe) 23, which passes through the body 1 (Fig. 3, 5).

The impeller Z can be made with flat blades 12. To ensure the intersection of the flat blades sl 12 with the surface of the cover disk 10 in a straight line, the design of the cover disk 10 in the area of attachment of the blades 12 of the impeller Z is made in accordance with the equations: y-(0.29- -0.01)x0.3 7; 2-(-0.39--0.01)x-0.27; ггеХ?у?, where: 2-21О is a relative coordinate directed along the axis of rotation of the impeller in the direction from the main 59 disk to the inlet of the impeller; с хАХ/О - relative coordinate perpendicular to the axis of rotation of the impeller; umo is a relative coordinate perpendicular to the 7 axis and the x axis;

KO - the relative radius of the impeller,

K, X, Y, 7 - current radius and current coordinates of the impeller; 60 r - the diameter of the impeller.

In addition, in the channel 8 of the channel fan, a screen 24 can be installed, which is connected to the walls of the housing 1 (Fig. 2), the edge 25 of which is directed towards the blades 12 and away from the cover disk 10 towards the main disk 11 by a distance Y equal to 0.01-0.10 of the width H of the blades 12 on the outer diameter Y of the impeller 3, and from the ends of the blades 12 at a distance C of at least 0.01 of the diameter O of the impeller 3: because I -(0.01-0.10) N; С»0.010, (Fig. 2, 8).

The channel fan is equipped with a vortex damper, which is located in the vortex cavity 7 (Fig. 1, 2, C).

The vortex suppressor can be made in the form of a guiding device, made in the form of at least one plate 26, which is installed in the vortex cavity 7 of the housing 1 in front of the confusing gap 16 (Fig. 1). When performing a channel fan with a screen 24, the directing device contains at least two plates 27, which are connected to the walls of the housing 1 and/or the screen 24 (Fig. 2).

In the preferred embodiment, the impeller C of the channel fan contains at least 9 bent back flat blades 12, which have a width of H»O.30, and a section of the generating cover disk 10, made according to the equations: y-(0.29 -0.01) x0.37, 2-(-0.39-0.01)x-0.27, g-x2vu?, which ensures the intersection of the blade edge 12 with the 70 surface of the cover disk 10 in a straight line (technological errors in the manufacture of the cover disk 10 and the wear of the equipment used in its manufacture can be: -0.01x), between the cover disk 10 and the suction nozzle 4 there is a confusing gap 16. The ratio of the cross-sectional area of the channel 8 to the area of the impeller Z is 5/Zrk-2.4- 3.0. The vortex damper is made in the form of a guiding device with at least one plate 26, which is installed in the vortex cavity 7 in front of the confusing gap 16. In the 75 version of the channel fan with a screen 24, the guiding device contains at least two plates 27, which are connected to the walls of the housing 1 and/or the screen 24 .

The engine 2 is located in the rear fairing 6, which is connected to the body 1 by means of 8-10 blades 17 (Fig. 4, 5). The blades 17 of the straightening device 5 are made with a length of (0.4-0.5)O0 of the diameter of the impeller Z, the front edge of the blades 17 stands at a distance of (0.1-0.3)N from the main disc 11 to the side of the cover disc 10, the inlet section of the blades 17 is made along an arc, which is inclined to the axis 15 and towards the direction of rotation of the impeller Z by approximately 452 (Fig. 7). The body 1 contains flanges 9 installed on the ends of the body, and is made of the front 28 and the back 29 parts connected to each other. In the front part 28 of the housing 1, the inlet manifold 4, the impeller Z and the engine 2 connected to it by means of the hub are installed. In the rear part 29 of the housing 1, the rear fairing b is installed, which is connected to the walls of the housing 1 by means of the blades 17 of the straightening device 5. To increase efficiency fan cooling, the rear fairing Z7Z is equipped with a plug 21, its cavity is connected to the atmosphere by means of an air duct 23, and holes 22 are made in the front wall 20 (Fig. 3, 5), while when using the fan to move hot air and gases, the main disc 11 is made perforated (with holes) for cooling the blades 12 and the cover disk 10 of the impeller Z (Fig. 4). IF)

The duct fan works as follows. at

The rotating cover disk 10 creates an annular vortex movement of air in the vortex cavity 7. The flow at the exit from the rotating impeller 3 has the kinetic energy of rotation and forms a dynamic pressure o гy2/2, where r is the air density, y is the circle the speed of the ends of the blades 12 on the outer diameter of the impeller so

C. Part of the flow coming out of the impeller 3 is sucked into the vortex cavity 7, and in interaction with the ring vortex forms a torus-shaped vortex in it. The introduction of the vortex suppressor into the vortex cavity 7 allows -:SM to destroy the toroidal vortex and turn its full pressure into static pressure. As a result of the difference in static pressure in the vortex cavity 7 and on the inner surface of the cover disc 10, an annular jet of air is formed, which flows out of the confusing annular gap 16 onto the inner surface of the cover disc 10. At the same time, the separation of the boundary layer (flow) on the inner surface of the cover disc 10 is prolonged , which allows you to increase the width of the blades 12 of the impeller 3, up to 0.38 of the diameter Y of the impeller 3: H-0.380 - without - with the deterioration of its aerodynamic characteristics. At the ratio of the area Z of the cross-section of the channel 8 (between the "» walls of the housing 1) to the area Zrk of the impeller, which corresponds to Z/Zrk»2.4 in the plane perpendicular to the "axis of symmetry of the inlet collector 4 at the place of installation of the impeller 3, the flow of the impeller C expands, the speed of the flow decreases, and the blades 17 of the straightening device 5 reduce the vorticity of the flow ("unwind" the flow), and thereby reduce the air speed, which contributes to an increase in static pressure. As a result, as shown in the graph in Fig. 9, the coefficient of static pressure increases (which is equal to the ratio of static pressure Rem to the product of air density by the square of the circumferential speed of the impeller blade шф2Ram/gy?) at a constant value of the productivity coefficient зу. Zrkyu, where 0 is the performance of the fan. At the same time, as studies have shown, the shape of the cross-section of channel 8 has a weak effect on pressure recovery. When the surface of channel 8 is made cylindrical (with a base contour in the form of a circle), losses due to aerodynamic resistance are reduced and the efficiency of the fan is increased. It was experimentally established that that when the toroidal vortex is destroyed by the vortex suppressor, the loss of the static pressure of the Ditch is reduced, which makes it possible to reduce the diameter of the channel 8. Thus, when the vortex suppressor is made in the form of a guiding device with plates 26, which are located in front of the confusing gap 16, as shown in Fig. 10, the coefficient of static pressure is 99 of the fan increases to the level of the free impeller 3. At the same time, a part of the air thrown by the blades 12 of the impeller 3 enters the vortex cavity 7, which allows the formation of an annular jet that flows through the confusing gap 16 onto the surface of the cover disk 10.

As a result, as shown in Fig. 11, the aerodynamic characteristics of the channel fan (graph 1) are significantly improved in comparison with the fan taken as the closest analogue (graph 2). 60 The presence of connecting flanges 9 on the ends of the housing 1 increases the manufacturability of connecting the duct fan to air ducts and other units of ventilation installations (heaters, filters, silencers, etc.) and reduces pressure losses due to the possibility of combining units without changing the cross-sectional area. Making the walls b of the housing 1 with panels that contain heat-insulating and/or sound-absorbing material (not shown in Fig.) reduces noise and increases the consumer properties of the fan. Execution of the working wheel 62 Z with flat blades 12 increases the manufacturability of the fan. When performing the surface of the cover disk 10 in the area of attachment of the flat blades 12 with the generator, which is performed according to the equations: y-(0.29-0.01)х--0.37, 2-(-0.394-0.01)х -0.27, гг-х2-у?, (these equations can be obtained by simple linear transformations of the coordinate system, the value --0.01 takes into account possible technological errors in the manufacture of the impeller 3) the combination of blades 12 with the surface of the cover disk 10 in a straight line is ensured , which increases the manufacturability of manufacturing the impeller Z while maintaining its high aerodynamic characteristics.

Fan equipment screen 24, which is connected to the walls of the housing 1 (Fig. 2, 8) with edges 25, which are directed to the blades 12 and the outer surface of the cover disk 10 of the impeller З and located at a distance of 70 І -(0.01-0, 10) H from the cover disk 10 towards the main disk 11 and from the blades 12 at a distance

C»0.010, prevents the suction of air into the vortex cavity 7 by a torus-shaped vortex, which leads to an increase in pressure in the cavity 7, as a result of which the intensity of the jet, which is blown out of the confusing annular gap 16, increases. The presence of a vortex damper in the vortex cavity 7, made, for example, in the form of the directing device, which contains at least two plates 27, which are connected to the walls of the housing 1 75 or the inlet collector 4 and/or the screen 24, additionally inhibits the flow, which increases the static pressure in the vortex cavity 7 and increases the intensity of the jet that is formed in the confusing gap 16 and is blown onto the surface of the cover disk 10.

A useful model can be implemented at any specialized enterprise. The set of features presented in the description is sufficient to create channel fans in a housing with a cylindrical channel without additional inventive creativity.

Claims (15)

The formula of the invention 1. A channel fan, which contains a cylindrical body, an inlet manifold, a rear fairing, an impeller kinematically connected to the engine, which is formed by the main and cover discs and blades bent back between the discs, an inlet manifold symmetrical about the axis, which is located on one of the ends of the housing, made with a curvilinear profile in the diametrical section with the formation of a confusing gap between the surfaces of the cover disc and the inlet collector, while the axis of rotation of the impeller IV) is made coaxial with the axis of symmetry of the inlet collector, a vortex cavity is formed between the inlet collector and the cover disc, and between the walls of the case - a channel, which differs in that the fan has a blade o straightening device, which is located behind the main disk of the impeller, the cross-sectional area of "3 channels is at least 2.4 areas of the circle describing the ends of the blades of the impeller, the rear fairing made taking into account the conical shape and combined with the walls of the channel with the blades of the steering device. at 2. Channel fan according to claim 71, which is characterized by the fact that SM vortex dampers are installed in the vortex cavity. 3. Channel fan according to claim 2, which is characterized by the fact that the vortex dampers are made in the form of a guiding device, which contains at least one plate, which is located in the vortex cavity. " 4. Duct fan according to claim 3, which is characterized by the fact that at least one plate of the vortex damper is connected to the duct wall and the inlet manifold. - with 5. Channel fan according to claim 1, which differs in that the motor is located in the rear fairing and is connected to the impeller by means of a hub located on the main disk. ," 6. Duct fan according to claim 5, which is characterized by the fact that the fairing is equipped with a front wall in which at least one hole for cooling the engine is made, while the part of the fairing in which the engine is located is made of a cylindrical shape, and the conical part is adjacent to the cylindrical, rear the end of the conical section can be equipped with a plug. with 7. Channel fan according to claim 5 or claim 6, which is characterized by the fact that the fan is equipped with a pipe for ventilation of the engine, which is pneumatically connected to the fairing, and the rear end of the conical section is equipped with (av) a plug. at 50 8. Channel fan according to claim 1, which is characterized by the fact that the blades of the straightening device are made with a length of 0.4-0.5 of the diameter of the impeller. sl 9. Channel fan according to claim 8, which is characterized by the fact that the front edge of the blades of the straightening device is located in front of the edge of the main disk at a distance of 0.1-0.3 of the width of the blades of the impeller. 10. Channel fan according to claim 8 or claim 9, which differs in that the front part of the blade of the straightening device is made in the form of an arc, the free edge of which is located at an angle of no more than 459 to the axis of rotation of the impeller in the direction of its rotation. 11. Channel fan according to claim 1, which differs in that the blades of the impeller are flat. 12. Channel fan according to claim 1, which is characterized by the fact that the generator of the curvilinear cover disk in the area of attachment of the impeller blades is made according to the equations: 60 Uu-(0.250.01)x0.37 g-(-0.39.0.01)x -0.27 te-heju?, where: 2-2/О0 - relative coordinate directed along the axis of rotation of the impeller in the direction from the main disk to the inlet of the impeller; because xАХ/О is a relative coordinate perpendicular to the axis of rotation of the impeller; umo is a relative coordinate perpendicular to the 7 axis and the x axis; KO - relative radius of the impeller, K - current radius of the impeller; X, Y, 2 - current coordinates; p - the diameter of the impeller. 13. Channel fan according to claim 1 or claim 2 or claim 4, which is characterized by the fact that a screen is installed in the housing channel, connected to the housing with the formation of a cavity between the screen, the housing and the suction nozzle, while the edge of the screen is located at a distance of 0 .01-0.10 of the width of the blades of the impeller from the cover disk towards the main disk and is not closer than 0.01 of the diameter of the impeller from the specified blades. 70 14. Duct fan according to claim 1 or claim 2, or claim 5, or claim 8, or claim 11, which is characterized by the fact that the housing includes interconnected front and rear parts, while the front part has an inlet manifold and the working wheel is connected to the engine, and in the rear part there is a fairing, which is connected to the walls of the body by means of the blades of the straightening device. 15. Channel fan according to claim 1, which is characterized by the fact that the main disk of the impeller is made with /5 ventilation holes. what with I c) (av) (av) Ge) p - a ko (95) (av) (av) sl bo b5