RU22978U1 - RADIAL FAN OPERATING WHEEL - Google Patents

Description

RADIAL FAN OPERATING WHEEL

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Ise more closely relates to the field of fan technology, namely,

to the design of the impeller with backward curved flat blades of the radial fan.

The impellers of radial fans are known in the art. So, in the Reference “Centrifugal fans. Aerodynamic schemes and characteristics authors T. S. Solomakhova and K.V. Chebysheva, Moscow, ed. Mechanical engineering, 1980, on page 101, Fig. 78, there is a diagram of a TsAGI fan of type Ts4-70, 1, an aerodynamic diagram of a centrifugal fan and an impeller containing a main and cover disks, flat blades located between the disks located between the disks located between the disks, is described concentric circles with a relative radius of 0.37 g 0.5, where: g R / D is the relative radius, R is the radius, m, D is the diameter of the impeller, m. The specified range of the relative radius g corresponds to yr.iy setting a flat blade relative to the tangent to the NOSTA with relative Radus gYu.74, shrfine blade .25 and rectilinear generatrix disk coating in the range & relates pnyh radii compound with flat blades.

A disadvantage of the known impeller 1J, taken as the closest analogue, is the connection of a flat blade with a conical surface of the covering disk (with a straight line generatrix) along a spatial line with the formation of a concave cavity (local diffusivity). A vortex comes into this cavity, which increases the impeller resistance and creates the conditions for the separation of the boundary layer from the covering disk. To prevent separation of the boundary layer, the width of the working blade is limited.

The technical task to be addressed is to improve the pressure flow characteristics and the efficiency of the impeller by preventing flow separation from the cover disk at the junction of the blade with the cover disk. The technical result consists in the implementation of a covering disk with a generatrix, in which the line of intersection of the blade with the surface of the covering disk is straight.

The essence of the utility model is as follows.

The impeller of a radial fan, as in the closest analogue f 1J, contains the main and cover disks, flat blades bent backward between the disks located between concentric circles with a relative radius of 0.37 g 0.5,

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but, unlike the closest analogue, at the junction of the blades with the cover disk at r.37 and gCh) 5, the cover disk intersects a conical surface with a straight line with a taper angle, and the cover disk is made in accordance with the system of equations: .287x +0.37

.392x-0.269

t t 1

,

where) is the relative coordinate directed along the axis of rotation of the impeller towards the entrance to the impeller from the main disk;

 - coordinate perpendicular to the axis of rotation of the impeller;

 - coordinate, perpendicular - the y-axis and x-axis; - dimensionless (relative) radius of the impeller, measured perpendicular to the axis of rotation of the impeller; R is the current radius of the impeller, m; X, Y Z - current coordinates, m; D is the diameter of the impeller, m

The presented features form the totality and are essential for solving the tasks and achieving the claimed technical result.

Indeed, the execution of the impeller of a radial fan, as in the closest analogue 1, containing the main and cover discs, flat blades backward bent between them 1 1 located between concentric circles with a relative radius of 0.37 g 0.5, provides good aerodynamic characteristics of the ventilator and simplicity of construction shoulder blades. The performance, in contrast to the closest analogue, of the cover disk at .37 and .5 intersecting with a conical surface with a rectilinear generatrix with a taper angle of 36 °, and forming a cover disk in accordance with the system of equations;

y-0.287x-fO.37

.392x-0.269

provides the intersection of a flat blade with the surface of the casing disk in a straight line. As a result, at the junction of the blades with the disk, a concave cavity (local diffuser) is not formed and the conditions for barking of vortices and separation of the boundary layer on the covering disk are not created.

The invention is illustrated by drawings.

In FIG. 1 shows the impeller in a side view

In FIG. 2. the section 1 -1 is given in Fig. 1.

The impeller of the radial fan is arranged as follows.

The impeller contains the main 1 and the cover 2 disks located between them flat backward curved blades 3, located between concentric circles with a relative radius of 0..5, the shaft 4 of the impeller. With a relative radius of .37 and G-S.5, corresponding to the intersection with the flush disk 2 of the inner and outer ends of the blades 3, respectively, the cover disk 2 intersects a conical surface with a rectilinear generatrix 5 with a taper angle of −36 °. The image of the skinny cone of the cover disk 2 in the range 0..5 of the connection with the blades 3 is made in accordance with the system of equations:

.287x + 0.37

.392x-0.269

1 1 1

g - x + y% where is the relative coordinate directed along the axis of rotation of the impeller towards the entrance 6 of the impeller from the main disk 1;

 - coordinate perpendicular to the axis of rotation of the impeller;

 - coordinate perpendicular to the z axis and x axis; - the relative radius of the impeller; R is the current radius of the impeller m; X, Y Z - current coordinates, m;

D is the diameter of the impeller at the junction of the external end of the blades 3 with the cover disk 2, m

The impeller of a radial fan operates as follows.

During the rotation of the impeller, an NPShimer by applying torque to the shaft 4, a boundary layer is formed on the surface of the disks 1, 2 and blades 3, the thickness of which increases with distance from the axis of rotation. Due to the implementation in the proposed manner of forming a covering disk, the intersection with the blades occurs in a straight line along which the boundary layer of vortex formation flows. This reduces the loss of resistance cores and increases the efficiency of the impeller.

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Claims (1)

1. The impeller of the radial fan, containing the main and cover disks, placed between the disks are flat curved backward blades located between concentric circles with a relative radius of 0.37≤r≤0.5, characterized in that at r = 0.37 and r = 0.5, the cover disk intersects with a conical surface with a rectilinear generatrix with a taper angle of 36 ^o , and the generatrix of the cover disk is made in accordance with the equations:
y = 0.287x + 0.37,
z = -0.392x - 0.269,
r ² = x ² + y ² ,
where z = Z / D is the relative coordinate directed along the axis of rotation of the impeller towards the entrance to the impeller from the main disk;
x = X / D is the relative coordinate perpendicular to the axis of rotation of the impeller;
y = Y / D is the relative coordinate perpendicular to the z axis and x axis;
r = R / D is the relative radius of the impeller, R is the current radius of the impeller, m;
X, Y, Z - current coordinates, m;
D is the diameter of the impeller, m