JPH029992A - Vortex turbomachinery - Google Patents

Abstract

PURPOSE:To make improvements in driving efficiency by forming a slat in the point midway in a blade, blowing off a clearance flow to the backside of the blade, and breaking a boundary layer. CONSTITUTION:When an impeller is rotated, a fluid is drawn in a main passage 24 from an inlet port 61, and in this main passage 24, it flows into a blade 35 from a blade front edge 35a of a first cascade 33, flowing out of a blade rear edge 36b of a second cascade 34, and it rotates in the main passage 24 and flows into the blade 35 again. Then, the fluid gets angular motion energy by blades 35, 36 and flows in the axial direction of the main passage as being rotated, then it is compressed by this spiral motion, and discharged to the out side of a housing 2 from a discharge port 62. During spiral motion of this fluid, a boundary layer is generated at the backside of the blade 36 of the second cascade 34. But a clearance flow is blown off to the backside of the blade 36 from a slat 8 between the first cascade 33 and the second cascade 34, break ing the said boundary layer. Therefore spacing between blades 35 and 36 is amply securable, and since any slip of the fluid due to the boundary layer is preventable, driving efficiency for compression performance or the like is well improved.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention applies to swirl-type vacuum pumps, compressors, turbines, etc., which give a spiral motion to a fluid by rotating an impeller and convert this angular kinetic energy into pressure. Regarding vortex type turbomachinery,
In particular, it relates to the structure of the impeller.

(Prior Art) Conventionally, this type of vortex type turbomachine has been equipped with an impeller having a large number of blades that is rotatable in a housing, as disclosed in Japanese Patent Application Laid-open No. 52-142313, for example. The impeller is rotated by the drive of the drive motor, the fluid is sucked into the main channel in the housing from the suction port of the housing, and the fluid is transferred in the main channel while being spirally moved in the axial direction of the main channel. It is known that the fuel is compressed while being compressed, and is discharged from the discharge port to the outside of the housing.

The impeller in this whirlpool turbomachine has a large number of blades extending radially around the outer peripheral surface of a hub, and the blades face the main flow path in the housing. And the above feather is
The hub is formed in a fan shape from the front surface to the outer peripheral surface of the rear end, and fluid flows into the blade from the leading edge of the blade, follows the circular arc surface of the outer peripheral surface of the hub, flows out from the trailing edge of the blade, and flows back into the blade. It will flow in from the leading edge, and this action will be repeated to create a spiral movement.

(Problem to be Solved by the Invention) However, in the above-mentioned vortex type turbomachine, the blades of the impeller are linearly continuous from the leading edge to the trailing edge.
Since the blade is formed into a plate-like body, and fluid passes between the blades, there is a problem in that a boundary layer is generated on the trailing edge side of the back surface of the blade, and the boundary layer develops toward the trailing edge. As the fluid slides due to this boundary layer, the spacing between the blades becomes smaller, making it impossible to sufficiently improve compression performance. In particular, in order to improve compression performance, it is desirable to increase the fluid outflow angle, but the boundary layer reduces the fluid outflow angle,
This was one of the causes of deterioration in compression performance.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to blow out a gap flow toward the back side of the blade from the middle of the blade, thereby breaking the boundary layer and improving drive efficiency. It is.

(Means for Solving the Problems) In order to achieve the above object, the means taken by the present invention is to form a slat in the middle of the blade so that a draft flow is blown out to the back side of the blade.

Specifically, the means taken by the invention according to claim (1) is as shown in FIGS. 1 and 4, first, the fluid suction port (6
1) and a housing (2) having a hollow annular portion (23) having a discharge port (62) and forming a main fluid passage (24); The fluid sucked into the main channel (24) from the suction port (61) is compressed while being transferred spirally to the discharge port (62).
) and an impeller (3) that discharges air from the housing (2) to the outside.

The impeller (3) has a first row of blades (33) on the inflow side and a second row of blades on the outflow side, which are composed of a plurality of blades (35) and (36) arranged facing the main flow path (24). (34) and the outer peripheral surface (31a) of the hub (31) and (32),
(:32a) are formed in parallel in the flow line direction of the fluid. Further, the blades (35) of each blade row (33) (34)
, (36) are provided in pairs, and are formed to have a predetermined warp. In addition, the blade leading edge (36a) of the second blade row (34) is connected to the first blade row (33).
) of the first blade row (33), and the blade trailing edge (35b) of the first blade row (33)
) and the blade leading edge (36a) of the second blade row (34).

Moreover, the means taken by the invention according to claim (2) is that the impeller (3) is divided into a first rotor (3a) and a second rotor (3b), and the first rotor (3a) is Hub (31)
The first blade row (33) is provided on the outer circumferential surface (31a) of the hub (32), and the second blade row (34) is provided on the outer peripheral surface (32a) of the hub (32), respectively. Both rotors (
3a).

(3b) are fixed to the side surfaces of the hubs (31) and (32).

Moreover, the means taken by the invention according to claim (3) is as shown in FIG.
and the leading edge (36a) of the blade of the second row of blades (34) are formed so as to overlap in the rotational direction, and the trailing edge (37b) of the blade of the first row of blades (33) and the leading edge of the blade (36a) of the second row of blades (34) overlap. ) blade leading edge (36
A passage-like slat (81) is formed between the slat (81) and the slat (81).

(Function) With the above configuration, in the invention according to claims (1) to (3), when the impeller (3) is rotated, fluid is sucked into the main flow path (24) from the suction port (61), and the fluid is sucked into the main flow path (24) through the suction port (61). (24), the blade leading edge (35a) of the first blade row (33), (37
a) into the blades (35) and (37), flows out from the blade trailing edge (36b) of the second blade row (34), and flows into the main channel (2).
4) and then flows into the vanes (35) and (37) again. The fluid then passes through the blades (35),
(36) and (37), the angular kinetic energy is obtained and the flow flows in the axial direction of the main channel (24) while rotating, and is compressed by this spiral movement and passes from the discharge port (62) to the housing (
2) It is discharged outside.

During the spiral movement of this fluid, the second blade row (3
A boundary layer occurs on the back side of the blade (36) in 4), but the first
Slats (8) between the blade row (33) and the second blade row (34)
), (81), a draft flow blows out to the back side of the blade (36) and destroys the boundary layer.

(Effect of the invention) Therefore, according to the vortex type turbomachine of the invention according to claim (1), the slat (
8), the boundary layer can be reliably destroyed, so that a sufficiently wide spacing between the vanes (36) can be ensured, and fluid slippage due to the boundary layer can be reliably prevented. As a result, drive efficiency such as compression performance can be improved. In particular, since the fluid outflow angle can be increased, performance can be reliably improved.

Furthermore, according to the invention according to claim (3), since the passage-like slats (81) exert a throttling action, the boundary layer can be reliably destroyed, and the performance can be further improved. .

Further, according to the invention according to claim (2), the impeller (3)
Since the rotors (3a) and (3b) are formed by two rotors (3a) and (3b), the rotors (3a) and (3b) can be easily cast and manufactured at low cost.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

As shown in FIGS. 1 and 2, (1) is a compression pump as a vortex type turbomachine, which compresses and discharges various fluids such as gas while transferring them in a spiral shape.

The compression pump (1) has an impeller (3) in a housing (2).
) is housed therein, and the housing (2) is formed by integrally combining a first housing member (21) and a second housing member (22) which are divided into left and right parts in FIG. has been done. and both housing members (21).

(22) includes disk portions (21a) and (22a) that cover both end surfaces of the impeller (3), and the disk portion (21a) and (22a).
a) Semi-torus part (21b), (22b) that is continuously formed on the outer peripheral edge of (22a) and has four semicircular annular parts
The two-handed torus portions (21b) and (22b)
forms a hollow annular part (23), and the central annular part (
23) is configured as a main fluid channel (24).

An annular guide member (4) for guiding the flow of fluid is disposed in the main channel (24) in the hollow annular part (23), and the outer peripheral surface of the guide member (4) and the hollow annular part ( 23)
The main flow path (24) is formed between the main flow path and the inner circumferential surface of the main flow path (24). Furthermore, a plurality of support pieces (41) protruding in the centrifugal direction are integrally formed on the outer peripheral portion of the guide member (4) at predetermined intervals in the circumferential direction. Then, the support piece (41
) of the hollow annular portion (23) of the housing (2).
), and the guide member (4) is fixedly supported by the housing (2) on the central axis of the main flow path (24).

Further, the main flow path (24) is provided with a stripper member (5) having a predetermined width extending from the inner peripheral surface of the hollow annular portion (23) to the outer peripheral surface of the guide member (4). 4), and divides the main flow path (24) into a high pressure side and a low pressure side. A guide path (5) through which the impeller (3) passes is provided in the inner circumference of the stripper member (5).
1), and a first housing member (2
A fluid suction port (61) is provided in the semi-torus part (21b) of 1).
However, on the other side (left side in FIG. 2), a fluid discharge port (62) is provided in the half-torus portion (22b) of the second housing member (22), and the fluid inlet port (61)
The fluid introduced from the stripper member (5) and the fluid discharged from the discharge port (62) are configured so as not to merge at the stripper member (5).

On the other hand, the impeller (3) is divided into a first rotor (3a) and a second rotor (3b), as shown in FIGS. 4 and 5, and both rotors (3a), (3b) are fixed together.

Both rotors (3a) and (3b) have a disk-shaped hub (3
1), (32) outer peripheral surfaces (31a), (32a
) are formed with an 11A row (33) and a second row of blades (34), and both hubs (31) and (32) are integrally fixed on the sides with adhesive, bolts, welding, etc. At the same time, the other side surfaces of both the hubs (31,) and (32) are closely covered by the disk portions (21a) and (22a) of the two housing members (21) and (22). Furthermore, both the hubs (31).

A drive shaft (7) is connected to the center of the housing member (32), and the drive shaft (7) is located concentrically with the main flow path (24). ), and a motor (not shown) is connected to the outer end thereof, and the impeller (3) is rotated by the drive of the motor.

Further, the outer circumferential surfaces (31a) and (32a) of both the hubs are formed as cylindrical surfaces concentric with the drive shaft (7), and constitute a part of the outer circumferential surface of the main flow path (24).

The first and 23rd A rows (33) and (34) are a plurality of blades (35) that protrude in the centrifugal direction from the hub outer peripheral surface (31a) and (32a) and face the main flow path (24),
(35), ... and (36), (36).

... are arranged at predetermined intervals, and the tips of the blades (35) and (36) are connected to the guide part shrine (4).
The first blade row (33) is formed so as to be close to the inner circumferential surface of the fluid, and the first blade row (33) is formed on the fluid inflow side, and the second blade row (34) is formed on the fluid outflow side.
are located and arranged in parallel in the flow line direction of the fluid. Furthermore, both the above-mentioned blade rows (33).

The blades (35) and (36) of (34) are arranged in pairs in the streamline direction, and the hub (31),
(32) are formed alternately on both sides.

Then, from the leading edge of the first blade row (38) to the second blade row (4
), the fluid passes over the trailing edge of both hubs (3).
1), the fluid passes from the front surface to the rear surface of the blade rows (33), (34), and the flow when passing through the blade rows (33), (34) becomes almost an axial flow, and angular kinetic energy is imparted to the fluid during this passage. The fluid is compressed while being transferred in a spiral direction within the main flow path (24).

In addition, the blades (35) of each of the blade rows (33) and (34),
(36) from the leading edge (35a), (36a) to the trailing edge (3
5b), (36b)l;l: Formed with arcuate blades with a predetermined curvature, the blades (35) of the first blade row (33) are curved rearward in the rotational direction (M), 2 rows of wings (
The blade (36) of 34) is formed to curve forward in the rotational direction (M). In other words, Figure 4 is Figure 3 IV-
It is a developed view cut along the circumferential surface concentric with the drive shaft (7) along line IV, and the leading edge (35a) of the blade (35) of the first blade row (33) is aligned with the drive shaft (7). It protrudes most forward in the rotational direction (M) without overlapping the blade trailing edge (35b) rearward in the rotational direction (M) with respect to the axial direction line (N), and extends backward in the rotational direction (M) toward the trailing edge (35b). The ventral surface (front surface) and the back surface (rear surface) are gradually positioned rearward in the rotational direction (M) without protruding forward toward the rear edge (35b). On the other hand, the leading edge of the blade (36) of the second blade row (34) overlaps the trailing edge (36b) of the blade at the rear in the rotational direction (M) with respect to the axial line (N) of the drive shaft (7). The rear edge (36
b) curves forward in the rotational direction (M), and the ventral surface (front surface) and dorsal surface 1Ii1i (posterior surface) are at the rear edge (36b)
It is formed so that it is gradually located forward in the rotational direction (M) without protruding backward in the rotational direction (M).

Furthermore, the leading edge (36a) of the blade in the second row (24) is further away from the trailing edge (35b) of the blade in the first row (33) in the rotational direction (M
) is formed so as to be located forward, and the first blade row (three
A space is provided between the blade trailing edge (35b) of 3) and the blade leading edge (36a) of the second blade row (34), and the slat (8)
is formed. The slats (8) guide a part of the fluid passing from the first blade row (33) to the second blade row (34) from the ventral side to the back side, and the clearance flow (C) causes the second blade row ( 34) is configured to destroy the boundary layer (L) generated on the back surface of the blade (36).

Next, the compression operation of this compression pump (1) will be explained.

First, when the motor is driven to rotate the drive shaft (7), the impeller (3) rotates within the housing (2), and each blade (3) rotates.
5), (35), ... and (36).

(36), . . . rotate in the main channel (24). On the other hand, the fluid is sucked into the main channel (24) in the housing (2) through the suction port (61), and the fluid is sucked into the main flow path (24) in the housing (2), and
) flows into the blade (35) from the blade leading edge (35a),
It flows to the blade (36) of the second blade row (34) and the trailing edge of the blade (
36b), and this blade (35),
(36) imparts angular kinetic energy to the fluid, causing it to rotate around the guide member (4) and again to the vane (
35) and (36). and,
The fluid is transferred in the axial direction of the main channel (24) while repeating the above-mentioned rotation, is compressed by spiral movement, and is discharged out of the housing (2) from the discharge port (62).

During this spiral movement of the fluid, the fluid moves into the blades (35),
(36), a boundary layer (L) is generated on the back side of (36) in the second blade row (34), and the boundary layer (L) develops toward the trailing edge (36b). However, when the fluid that has flowed into the blades (35) of the first blade row (33) flows into the blades (36) of the second blade row (35), a portion of the fluid flows into the side plates (35), ( 36), and blows out from the ventral side to the back side, creating a draft flow (c). This clearance flow (C) creates the boundary layer (L) on the back surface of the blades (36) of the second blade row (34).
will be destroyed.

Therefore, since this boundary layer (L) can be reliably destroyed, a sufficiently wide spacing between the blades (36) can be ensured, and fluid slippage due to the boundary layer (L) can be reliably prevented. Since it is possible to do this, compression performance can be improved. In particular, since the fluid outflow angle can be increased, performance can be reliably improved.

Next, a method of forming the impeller (3) will be explained.

Note that the impeller (3) has both rotors (31).

(32) are molded separately, and both rotors (31) (3
Since the molding method of 2) is the same, the 20th evening (32)
I will explain about it.

As shown in FIG. 6, the second rotor (32) is formed by casting using an upper mold (10) and a lower mold (11). Both types (10) and (11) are divided into upper and lower parts on a plane orthogonal to the drive shaft (7) so as to be combined with the front side and the rear side of the second rotor (32), and the blades (
36) is along the axial line (36b) passing through the blade trailing edge (36b).
N). In other words, the above upper mold (
10) is a concave surface (10a) along the back surface of the blade (36)
The lower mold (11) is formed from the convex surface (11a) along the ventral surface of the blade (36) to the flat surface (10b) along the axial line (N). ) is formed up to a flat surface (1l b). Therefore, the second rotor (32) is cast by combining the two molds (10) and (11) and pouring the molten metal into the molds.

Therefore, the first rotor (31) and the second rotor (32)
If you try to integrally mold them by casting, the first rotor (31
) of the first rotor (
Since the trailing edge (35b) of the blade (31) and the leading edge (36a) of the blade of the second rotor (32) are located at the rear in the rotational direction, each blade (35), C3, is recessed from the axial direction line (N).
The ventral surface of 6) cannot be easily formed by casting, and requires machining with an end mill or casting processing such as a lost wax method.

Therefore, as mentioned above, the impeller (3) is connected to the first rotor (31).
and the 20th rotor (32), and after separately casting and molding the two rotors (31).

(32) are fixed together.

FIGS. 7 and 8 show other embodiments, and the 10th-evening (3
The blades (37) in a) are slightly extended to the second rotor (3b).

In other words, the blade (37) of the first rotor (3a) has a leading edge (
37a) and the trailing edge (37b) are formed into sharp shapes as in the previous embodiment, and are also formed into arcuate blades having a predetermined curvature. Furthermore, the blade trailing edge (37b) is slightly extended toward the back side of the blade leading edge (36a) of the second rotor (3b), and as shown in FIG. 7(A), both rotors are The blade trailing edge (37b) and blade leading edge (36a) of (3a) and (3b) are formed to overlap. Then, the blade trailing edge (37b
A passage-like slat (81) is formed between the portion ) and the leading edge (36a) of the blade, and the slat (81) allows the fluid on the ventral surface side of the blade (37) in the first rotor (3a) to flow through the slat (81). part is blown out to the back side of the blade (36) in the second rotor (3b).

Therefore, the fluid passing through the slat (81) is accelerated by the throttling action of the slat (81), and the fluid is accelerated to the second rotor (3b).
), the boundary layer (L) on the back side is more reliably destroyed, and the compression performance can be further improved.

In addition, in this embodiment, the impeller (3) is connected to two rotors (
3a) and (3b), but one rotor has two
Two rows of blades (33) and (34) may be formed.

In addition, in the impeller (3) shown in Fig. 7, the second blade row (
The leading edge (36a) of the blade 34) may be extended toward the first blade row (33).

Moreover, it goes without saying that the vortex type turbomachine of the present invention may be a vacuum pump, a turbine, or the like in addition to the compression pump (1).

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a longitudinal sectional view of a compression pump, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 3 is an enlarged sectional view of the main part of FIG. 2. It is. FIG. 4 is a developed view of the impeller (3) taken along line IV-IV in FIG. 3, and FIG. 5 is a rear view of the main parts of the impeller. FIG. 6 is a cross-sectional view of the main parts of the impeller mold. 7 and 8 show other impellers, with FIG. 7 being a developed view corresponding to FIG. 4, and FIG. 8 being a rear view corresponding to FIG. 5. (1)...Compression pump, (2)...Housing, (
3)... Impeller, (3a), (3b)... Rotor, (5)... Stripper member, (7)... Drive shaft, (8) (81)... Slat, ( 2B)...Hollow annular part, (24)...Main channel, (31), (32
)...Hub, (33), (34)...Blade row, (
35), (36). (37) ... Feather, (35a), (36a),
(37a) =-・leading edge, (35b), (36b)
, (37b)... trailing edge, (61)... suction port,
(62)...Discharge port.

Claims (3)

[Claims] (1) A housing (2) having a hollow annular portion (23) having a fluid suction port (61) and a fluid discharge port (62) and forming a main fluid channel (24); ), and the above suction port (
61), the fluid sucked into the main channel (24) is compressed while being transferred in a spiral manner, and the fluid is drawn into the housing (2) from the discharge port (62).
) A whirlpool type turbomachine equipped with an impeller (3) for discharging air to the outside, the impeller (3) comprising a plurality of blades (35) and (36) arranged facing the main flow path (24). The first blade row (33) on the inflow side and the second blade row (34) on the outflow side form a hub (31).
, (32) are arranged in parallel in the flow line direction of the fluid on the outer circumferential surfaces (31a), (32a) of the blades (35), (36) of each of the blade rows (33), (34).
are provided in pairs and are formed to have a predetermined curvature, and the blade leading edge (36a) of the second blade row (34) rotates more than the blade trailing edge (35b) of the first blade row (33). The blade trailing edge (
35b) and the blade leading edge (36a) of the second blade row (34). (2) The impeller (3) is divided into a first rotor (3a) and a second rotor (3b), and the first rotor (3a) has a first rotor attached to the outer peripheral surface (31a) of the hub (31). The blade row (33) is connected to the second rotor (3b) on the outer peripheral surface (32a) of the hub (32).
) are each provided with a second blade row (34),
Both rotors (3a) and (3b) are connected to hubs (31) and (32).
) is fixed on the side of the claim (
1) The vortex type turbomachine described above. (3) The trailing edge (37b) of the blade of the first blade row (33) and the leading edge (36a) of the blade of the second blade row (34) are formed so as to overlap when viewed in the rotational direction, and The trailing edge of the blade (33) (
37b) and the blade leading edge (36a) of the second blade row (34), a passage-like slat (81) is formed between the vortex flow according to claim (1) or (2). Shape turbomachinery.