KR102163586B1 - Integrated Multi-Step Inducer - Google Patents

Abstract

The present invention relates to an integrated multi-stage inducer in which a plurality of blades of different sizes are formed as a multi-stage integral, the integrated multi-stage inducer of the present invention in the inducer comprising a blade extending from one side of the shaft to the other, the blade The front end formed on the front side, the rear end formed on the rear side of the front end and having a larger radius than the end of the front end, and a transition part in which the radius and thickness continuously change between the end of the front end and the start of the rear end are integrated It is formed by adopting an auxiliary inducer with a small diameter to improve the suction performance of the pump, while preventing the overall shaft length from being extended, thereby preventing an increase in the weight of the system and improving the shaft dynamic stability. I can.

Description

Integrated Multi-Step Inducer

The present invention relates to an inducer that is installed in a pump to improve the suction performance of the pump, and more particularly, to an integrated multi-stage inducer in which a single or a plurality of blades of different sizes are formed as a multi-stage integral.

The projectile gains propulsion by injecting fuel and oxidant by burning it in the combustion chamber. To obtain a large propulsive force, the fuel and oxidant stored in the tank must be pressurized at high pressure and supplied to the combustion chamber. There are two methods of supplying fuel and oxidizing agent by pressurizing the combustion chamber. One is a pressurization type that directly pressurizes the fuel and oxidizing agent tank, and a pump type that pressurizes and supplies low-pressure fuel and oxidizing agent through a pump.

Although the pressurized type has the advantage of being simple, there is a disadvantage in that the structure ratio of the projectile is deteriorated due to an increase in the weight of the tank to support the high pressure. On the other hand, the pump method stores fuel and oxidant at low pressure in the tank and pressurizes it in the pump, so it is possible to reduce the weight of the projectile, thereby improving the structure ratio, and has the advantage of enabling a large thrust. It requires advanced technology to control vibration and cavitation. Since the suction performance of the pump greatly affects the structure ratio and performance of the entire projectile, it is very important to improve the suction performance of the pump.

On the other hand, the inducer is installed in front of the impeller of the pump rotating at high speed or is installed alone to lower the effective suction head (NPSH) to prevent performance degradation due to cavitation of the pump. These inducers are used in various fluid machines that require high suction performance.

In order to provide a more improved suction performance of the pump through the inducer, conventionally, as shown in FIG. 1, a small auxiliary inducer 3 is additionally installed in front of the main inducer 2 at a predetermined distance. A method has been developed to maximize In detail, in the case of the auxiliary inducer (3) with a small radius of the inducer in general, the efficiency and lift are low because the tip clearance is large, but the rotational speed of the blade tip is small, so it can be operated even at low inlet pressure, and the main reason has a large radius. By raising a certain head in front of the transducer (2), the effective suction head (NPSH) of the main inducer is increased, so that the pump can operate at a lower pressure as a whole.

However, in the case of the two-stage inducer having the structure as described above, the auxiliary inducer 3 and the main inducer 2 are formed separately, and the weight increases and the shaft system dynamics in terms of the overall shaft length increases. There were disadvantages and problems such as a change in the design structure of the entire projectile system due to an increase in inducer length. In addition, the flow flow is not stable due to the sudden change of the wing structure in the section between the auxiliary inducer (3) and the main inducer (2), and the angle of the front end of the auxiliary inducer (3) and the main inducer (2) If not properly matched, there is a concern about loss of suction performance and loss of hydraulic performance, and thus there was a hassle.

Accordingly, there is a need to develop an inducer capable of improving the suction performance of the pump and eliminating the inconvenience of installation as described above.

1. Korean Patent Registration No. 10-0933044 ("Inducer equipped with a circulation channel") 2. Korean Patent Registration No. 10-0625845 ("Inducer equipped with entrance guide wings") 3. Korean Patent Registration No. 10-1164806 ("High Performance Inducer") 4. Korean Patent Registration No. 10-0392786 ("Pump inducer with cavity phenomenon elimination structure") 5. Korean Patent Publication No. 10-2014-0123949 ("Inducer")

The present invention was conceived to solve the above problems, and the present invention provides an integrated multi-stage inducer that does not greatly extend the overall shaft length while employing an auxiliary inducer with a small diameter in order to improve the suction performance of the pump. It aims to do.

In addition, the present invention forms a transition portion between the front end portion having a small radius and the rear end portion having a large radius so as to stabilize the flow flow between the auxiliary inducer and the main inducer, It aims to provide an integrated multi-stage inducer that can stabilize the flow.

In addition, the present invention changes the radius ratio of the front end and the rear end and the angle of the transition part instead of adjusting the distance between the auxiliary inducer and the main inducer, and it is troublesome to adjust the installation position of the auxiliary inducer and the main inducer. It aims to provide an integrated multi-stage inducer that can solve the problem.

The integrated multi-stage inducer of the present invention includes a wing extending from one side of the shaft to the other side, and in the inducer installed on the pump, the wing is formed on the front side, and the radius gradually increases from the front side to the rear side. The front end and the rear end of the front end and the rear end of the front end are constant between the front end and the rear end of the front end and a rear end having a larger radius than the end of the front end, but having a constant radius Section overlapping, the front surface includes a transition portion formed in the shape of the front end, the rear surface includes a transition portion formed in the shape of the rear end, and the radius of the rear end of the front end positioned in the transition portion is the rear end located at the transition portion It is smaller than the radius of the starting end of the negative, and the transition part is formed at an angle of 45 degrees or less.

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In addition, the transition portion is characterized in that the thickness continuously changes between the end of the front end and the start of the rear end.

In addition, the radius of the front end is formed in a range of 10% to 90% of the radius of the rear end, and the size of the gap formed between the outer end of the rear end and the inner diameter of the pump inlet is between 0.005 and 0.03 times the radius of the rear end. It is characterized by being formed.

In addition, the axial length occupied by the rear end may be longer than the axial length occupied by the front end.

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In addition, the transition portion is characterized in that formed by forming an angle within 90° from the start end of the rear end to the end of the front end.

Through the above solution, the integrated multistage inducer of the present invention employs an auxiliary inducer having a small diameter to improve the suction performance of the pump, while preventing the overall shaft length from being greatly extended, thereby increasing the weight of the system. Can be prevented, and the shaft dynamic stability can be improved.

In addition, it is possible to solve the difficulty in selecting an installation location between the auxiliary inducer and the main inducer through the integrally formed front and rear ends.

In addition, there is an effect of stabilizing the flow flow between the front end and the rear end as much as possible through the configuration of the transition portion in which the radius and the thickness continuously change.

In addition, the diameter, length, and number of each of the front and rear blades, the gap formed between the inner diameter of the pump inlet, and the angular distribution may have an appropriate shape according to the suction performance, efficiency, and head required by the pump. .

1 is a side view illustrating a conventional auxiliary inducer and a main inducer installed on a shaft separately.
2 is a side view of an integrated multi-stage inducer according to a preferred embodiment of the present invention.
3 is a perspective view of an integrated multi-stage inducer according to a preferred embodiment of the present invention.
4 is a perspective view showing a front end of an integrated multi-stage inducer according to a preferred embodiment of the present invention.
5 is a perspective view illustrating a transition part of an integrated multi-stage inducer according to a preferred embodiment of the present invention.
6 is a perspective view showing a rear end of an integrated multi-stage inducer according to a preferred embodiment of the present invention.
7 is a perspective view showing each portion of an integrated multi-stage inducer according to a preferred embodiment of the present invention.
8 is a front view showing the shape of the transition part of the integrated multi-stage inducer according to a preferred embodiment of the present invention.
9 is a side view showing the radius of the front end and the rear end of the integrated multi-stage inducer according to a preferred embodiment of the present invention.
10 is a side view illustrating a length ratio of a front end portion and a rear end portion of an integrated multi-stage inducer according to a preferred embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

The accompanying drawings are only an example shown to describe the technical idea of the present invention in more detail, so the technical idea of the present invention is not limited to the form of the accompanying drawings.

In the direction display of the present invention, the upper side of the drawing is defined as the upper side, the lower side of the drawing is the lower side, the left side in the longitudinal direction of the drawing is defined as the front side, and the right side is the rear side.

FIG. 2 is a side view of an integrated multi-stage inducer 10 according to a preferred embodiment of the present invention, and the integrated multi-stage inducer 10 according to a preferred embodiment of the present invention is shown in FIG. And a blade 110 extending along the shaft 100 from one end of the shaft 100 to the other end, and is installed in the pump to improve the suction performance of the pump. At this time, the blade 110 of the integrated multi-stage inducer 10 of the present invention has a front end 300 forming a front side and a front end 300 having a larger diameter than the blade and forming the rear side of the blade 110 It is formed including a rear end portion 700 and a transition portion 500 to which the front end portion 300 and the rear end portion 700 are connected to each other.

3 is a perspective view of an integrated multi-stage inducer 10 according to a preferred embodiment of the present invention. Referring to FIG. 3, the wing 110 of the integrated multi-stage inducer 10 according to a preferred embodiment of the present invention is constant. It includes a first wing 111, a second wing 131, and a third wing 151 arranged at an angle. The embodiment of the present invention shown in FIGS. 2 to 10 only shows a structure in which three blades are arranged in a spiral, but the number of blades may be formed as one, or may be formed in plural, as necessary. It is possible to increase or decrease the number of wings 110 accordingly. It is also possible to configure different numbers of wings at the front and rear ends.

4 is a perspective view for explaining a front end of an integrated multi-stage inducer according to a preferred embodiment of the present invention, and an area of the front end 300 is indicated by'o'.

Referring to FIG. 4, the front end portion 300 of the integrated multi-stage inducer 10 of the present invention is formed along the direction of the shaft 100, and the radius gradually increases toward the rear for structural stability of the wing. Doedoe, the maximum radius of the front end 300 is formed smaller than the radius of the rear end 700 to be described later. When the wings of the front end 300 can be sufficiently sturdy, all radii of the wings can be configured equal to the maximum radius.

5 is a perspective view for explaining a transition part of an integrated multi-stage inducer according to a preferred embodiment of the present invention, and an area of the transition part 500 is indicated by'△'.

5, the transition part 500 of the integrated multi-stage inducer 10 of the present invention is a region formed at the end of the front end 300, the front end 300 and the rear end 700 to be described later. ) Is connected, and the shape of the front end 300 and the shape of the rear end 700 to be described later are formed in combination, and the flow flow that flows according to the shape of the front end 300 gradually increases due to its shape characteristics. As a result, by inducing to change into a flow flow according to the shape of the rear end portion 700, performance degradation due to a rapid change in flow flow is prevented.

6 is a perspective view for explaining the rear end of the integrated multi-stage inducer according to a preferred embodiment of the present invention, and an area of the rear end 700 is indicated by'ㅁ'.

Referring to FIG. 6, it is connected to the rear end of the transition part 500 of the integrated multi-stage inducer 10 of the present invention to form the other end of the integrated multi-stage inducer 10. At this time, the rear end 700 is formed larger than the radius of the front end 300 and the tip gap is formed to be smaller, thereby further improving the pump head, efficiency and suction performance.

7 is a perspective view showing a front end, a transition part, and a rear end of an integrated multistage inducer according to a preferred embodiment of the present invention, and referring to FIG. 7, an integrated multistage inducer 10 according to a preferred embodiment of the present invention ) Secures a certain level of the pump head through the front end portion 300 with a small radius, gradually changes the flow flow of the fluid sucked through the transition portion 500, and pumps through the rear end portion 700 with a large radius. The lift, efficiency and suction performance are further improved, and the front end 300 acting as the auxiliary inducer and the rear end 700 acting as the main inducer are integrally formed to shorten the length of the shaft. In addition, since the transition part 500 whose radius, angle, thickness, etc. continuously change, connects the front end 300 and the rear end 700, it is possible to prevent performance degradation due to a rapid change in flow flow.

Figure 8 is a front view for showing the shape of the transition part 500 of the integrated multi-stage inducer according to a preferred embodiment of the present invention, referring to Figure 8, the shaft between the front end 300 and the rear end 700 ( 100) is formed at a predetermined angle α, the front surface 510 of the transition portion 500 is formed in the shape of the front end portion 300, and the rear surface 530 of the transition portion 500 is It is formed in the shape of the rear end 700, and has a shape in which the front end 300 and the rear end 700 are formed in combination.

The transition part 500 of the present invention mitigates the change in flow flow according to the difference in radius between the front end 300 and the rear end 700 through the shape as described above. In other words, the transition part 500 allows a part of the fluid flowing into the transition part 500 to follow the flow flow of the front part 300 through the shape of the front surface 510, and through the shape of the rear surface 530 Part of the fluid introduced into the transition part 500 follows the moving flow that appears at the rear end part 700. In addition, the shape of the transition part 500 gradually becomes similar to the shape of the rear end 700 as it progresses toward the rear side of the shaft 100 along the spiral shape of the wing shape around the shaft 100. You can make a difference.

9 shows a form in which the integrated multi-stage inducer 10 is installed in the tube according to a preferred embodiment of the present invention. In general, a gap is formed between the outer end of the rotating inducer and the inner diameter of the fixed pump inlet (1), and the gap between the blade of the inducer and the inner diameter of the tube, that is, the greater the tip gap (x) Although the efficiency and the head are lowered, if the tip clearance x is too small, there may be friction between the blade and the inner diameter of the pump, and thus it is necessary to set the tip clearance x appropriately.

Referring to FIG. 9, in the integrated multistage inducer 10 of the present invention, a front end portion 300 having a small radius and a rear end portion 700 having a large radius are integrally formed, and the radius R of the rear end portion 700 The tip clearance (x) is set based on, but in the case of the front end portion 300 with a small radius of the inducer, the rotational speed of the wing tip is small, so that normal operation at a lower pressure than the rear end portion 700 having a large radius It is possible to improve the overall suction power of the pump by increasing the head in front of the rear end 700 in a very low effective head (NPSH) condition. However, since the performance of the front end portion is low due to the large tip clearance, it is preferable to be configured shorter than the rear end portion so as to have a smaller head than the rear end portion 700.

That is, in the integrated multistage inducer 10 according to the preferred embodiment of the present invention, through the structure as described above, the fluid firstly introduced by the front end 300 passes through the front end 300 to lift a certain amount This rises to increase the effective suction lift of the second half, and the fluid that has passed through the front end 300 is again supplied to the highly efficient rear end 700 to achieve an effect of exhibiting a further improved performance.

At this time, if the maximum radius r of the front end 300 is formed too small, the blade is caused by a rapid change in the flow flow in the section between the auxiliary iron western part 300 and the rear end 700, that is, in the transition part 500. There is a possibility that vibration and performance degradation may occur in (110), and due to the large tip clearance and small wing radius of the front end portion 300, it cannot have a sufficient lift, and conversely, the maximum radius (r) of the front end portion 300 If the rear end portion 700 is formed similarly to the radius R, the effect of improving the suction performance according to the small rotational speed of the front end portion 300 cannot be exhibited. As described above, the maximum of the front end portion 300 The ratio of the radius (r) and the radius (R) of the rear end portion 700 must be properly set.

Preferably, the tip gap (x) of the rear end (700) is formed between 0.005 to 0.03 times the radius of the rear end (700), and the maximum radius (r) of the front end (300) is It is formed smaller than the radius R, and the maximum radius r of the front end 300 may be set in a range of 10% to 90% of the radius R of the rear end 700 according to required performance.

Referring to FIG. 8 again, since the maximum radius r of the end of the front end 300 is set smaller than the radius R of the rear end 700, the end and the rear end 700 of the front end 300 It is preferable that the transition part 500 connecting the start end of) is formed in a shape in which the radius gradually increases for structural stability.

At this time, the rear surface 530 of the transition part 500, that is, the portion formed so that its radius gradually increases from the end of the front part 300, the thickness in the front-rear direction gradually increases as it progresses to the rear side of the shaft 100, It is preferable that the thickness of the transition portion 500 at the end of the transition portion 500 is smoothly connected to the rear end portion 700 in accordance with the thickness of the start portion of the rear end portion 700. The region in which the transition part 500 is set varies according to the ratio of the maximum radius r of the front end 300 and the radius R of the rear end 700. At this time, if the setting area of the transition part 500 is too large, the auxiliary inducer role of the front end 300 is not properly performed, so that the rear end from the end of the front end 300 around the shaft 100 ( The angle α from the start end of 700) is preferably designed to be within 90°, and more preferably, the angle α from the start end of the front end 300 to the rear end 700 is It is good to be formed within 45°.

On the other hand, if the setting area of the transition part 500 is too small, uneven flow flow and flow shock may occur due to a sudden change in radius, so that the maximum radius r of the front part 300 is It is good to secure a minimum setting area according to the ratio of the radius R.

FIG. 10 is a side view showing the length ratio of the front end and the rear end of the integrated multistage inducer according to a preferred embodiment of the present invention. Referring to FIG. 10, a rear end 700 having a small tip gap and excellent hydraulic performance The axial length L occupied by is preferably formed to be longer than the axial length l occupied by the front end 300.

The integrated multi-stage inducer according to another preferred embodiment of the present invention is installed in the pump as in the above-described embodiment to improve the suction performance of the pump, and includes a shaft and a blade formed spirally extending from the front of the shaft to the other end. It has a containing structure. In addition, a front end portion forming a front portion of the wing, a rear end portion forming a rear portion of the wing, and a transition portion forming a connection section between the front end portion and the rear end portion are formed on the wing.

Similar to the above-described embodiment, the front end portion is formed to have a smaller radius than the rear end portion. The transition portion is formed with an end point of the front end as a starting point and has a radius equal to the radius of the rear end. The front surface of the transition portion is formed by the radius of the front end, and the rear surface of the transition portion is formed stepped to the radius of the rear end. In this case, as the transition portion proceeds to the rear of the shaft according to the shape of the blade, the rear surface, that is, the front-rear thickness ratio of the portion formed by the radius of the rear end becomes larger.

The integrated multi-stage inducer according to another preferred embodiment of the present invention does not have a shape that gradually increases from the radius of the front end to the radius of the rear end as the outer diameter of the transition part progresses toward the rear of the axis, but the point where the front end ends. As the starting point, it takes a shape that changes rapidly to the outer diameter of the rear end. Therefore, since the transition portion may exhibit an unstable flow flow compared to the transition portion disclosed in the above-described embodiment, it is preferable to form the radius of the front end to 60% or more and 80% or less of the radius of the rear end.

A description of the operation of the integrated multi-stage inducer according to another preferred embodiment of the present invention is similar to that of the above-described embodiment, and will be omitted since it can be sufficiently inferred from the description in the above-described embodiment.

The technical idea should not be interpreted as limited to the above-described embodiment of the present invention. As well as a variety of application ranges, various modifications can be made at the level of those skilled in the art without departing from the gist of the present invention claimed in the claims. Therefore, these improvements and changes will fall within the scope of protection of the present invention as long as it is apparent to those skilled in the art.

1: pump inlet
2: primary inducer 3: secondary inducer
10: Integrated multistage inducer of the present invention
100: axis
110: wing
111: first wing 131: second wing 151: third wing
300: front end
500: transition part
510: front surface of the transition portion 530: rear surface of the transition portion
700: rear end
A: A specific point where the radius of the front surface of the transition part starts to increase
B: the point where the radius of the rear surface of the transition part reaches the radius of the rear end
r: maximum radius of the front end
R: radius of the rear end
l: axial length of the front end
L: axial length of the rear end
x: tip clearance at the rear end
α: The angle of formation of the transition part around the axis

Claims (7)

In the inducer installed on the pump comprising a blade extending from one side of the shaft to the other side,
The wings,
A front end portion formed on the front side, but gradually increasing in radius from the front side to the rear side,
It is formed on the rear side of the front end, and has a larger radius than the end of the front end, and a rear end having a constant radius,
Between the front end and the rear end, the rear end of the front end and the start end of the rear end are overlapped for a predetermined period, and the front surface includes a transition portion formed in the shape of the front end and the rear surface is formed in the shape of the rear end,
The radius of the rear end of the front end part located in the transition part is smaller than the radius of the start end of the rear end part located in the transition part,
An integrated multi-stage inducer, characterized in that the transition portion is formed at an angle of 45 degrees or less.
delete The method of claim 1,
The transition part,
An integral multi-stage inducer, characterized in that the thickness continuously changes between the end of the front end and the start of the rear end.
The method of claim 1,
The radius of the front end is formed in a range of 10% to 90% of the radius of the rear end,
An integrated multistage inducer, characterized in that the size of the gap formed between the outer end of the rear end and the inner diameter of the pump inlet is formed between 0.005 and 0.03 times the radius of the rear end.
The method of claim 1,
An integrated multistage inducer, characterized in that the axial length occupied by the rear end is formed longer than the axial length occupied by the front end.
delete The method of claim 5,
The transition part,
An integrated multi-stage inducer, characterized in that the angle from the start end of the rear end to the end end of the front end is formed within 90°.

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