KR20170001306A - Compressor for expansion of operating range - Google Patents

Abstract

Disclosed is a compressor of which an operational range is enlarged. The compressor of which the operational range is enlarged includes a passage wherein a cooling element flows in a casing inlet, a casing outlet, and a diffuser of the compressor. Accordingly, the purpose of the present invention is to prevent a surge phenomenon such as a flow blockage or a backflow in the casing inlet by improving performance with the enlarged operation range that the minimum inlet volumetric flow and the maximum outlet volumetric flow enabling the operation of the compressor are increased higher than an existing compressor at an outlet pressure while simultaneously or selectively supplying each cooling element to the inlet and the outlet of a casing of the compressor, to minimize a loss of a flow rate of a fluid by reducing outlet volumetric flows of an internal space of the diffuser and the casing outlet to decrease a velocity of the increased flow while increasing the flow rate of the fluid, and to reduce production costs for designing the compressor by enabling a design of the miniaturized compressor casing while increasing the compressing efficiency of the compressor.

Description

[0001] The present invention relates to a compressor having an expanded operating range,

The present invention relates to a compressor, and more particularly, to a compressor that simultaneously or selectively supplies cooling elements to an inlet side and an outlet side of a compressor casing, while minimizing a minimum inlet volumetric flow rate and a maximum inlet volumetric flow rate, Improved performance in an upwardly enlarged operation area suppresses surge phenomena such as flow clogging and reverse flow at the casing inlet side and increases the flow rate of the casing outlet fluid (eg gas, air, refrigerant, etc.) And more particularly to an expanded compressor operating area that reduces the flow loss of the fluid by increasing the speed of the increased fluid and increases the compression efficiency of the compressor.

Generally, a gas or centrifugal compressor (hereinafter referred to as "compressor") compresses a fluid such as gas or air introduced from a casing inlet by rotating an impeller having a plurality of blades in a casing by a rotary shaft. The flow of the formed fluid passes through the diffuser and the volute at the outlet of the casing in accordance with the rotation of the impeller and is discharged to the outside.

At this time, the diffuser is a fluid passage formed between the casing outlet and the volute, and functions to recover the dynamic pressure to a static pressure by decelerating the fluid discharged from the casing outlet.

That is, a normal compressor accelerates and compresses a fluid by a centrifugal compressing force of a impeller by passing a fluid through a rotating impeller, and the diffuser passage is connected to a casing outlet to reduce noises and increase the blowing efficiency, To convert the kinetic energy of the fluid into pressure energy.

However, in the conventional compressor, when the flow rate of the fluid passing through the impeller decreases, or when the pressure difference between the inlet and outlet of the casing becomes small, the fluid becomes unstable and the back flow of the fluid occurs in the diffuser, There is a problem that the efficiency is greatly lowered.

Conventionally, a variable diffuser system is constructed at the outlet of the casing to block backflow of the fluid and to control the maximum controllable flow range for the fluid, as disclosed in Japanese Patent Laid-Open No. 10-2010-0100239 So as to prevent the surge phenomenon as described above.

In other words, since the compressor is a device that is compressed at low pressure to high pressure unlike a turbine in which the flow direction of the fluid flows in a direction from a high pressure to a low pressure, a surge phenomenon is inevitably generated at a low flow rate. The flow rate of the gas is actively supplied from the outside, or the diffuser is changed to a variable diffuser system as a passive method as in the above-described prior art.

However, although the passive method of changing the diffuser can be used for a very limited purpose to prevent surge phenomena and increase the maximum flow range, it is limited to the casing inlet, and the adjustment of the volumetric flow rate to the casing outlet side of the compressor The flow rate of the fluid can not be reduced. Accordingly, conventionally, a flow loss to the fluid at the casing outlet side is generated, and the compression efficiency of the compressor is lowered, and the operation range is also limited.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide a refrigeration system in which the inlet and outlet sides of a compressor and a flow path, Elements can be simultaneously or selectively supplied, and the performance can be improved to an enlarged operating range in which the minimum inlet volumetric flow rate and the maximum inlet volumetric flow rate that can be operated on the basis of the outlet pressure as compared with the conventional one are improved, and the surge such as flow clogging or reverse flow on the inlet side of the casing thereby suppressing the surge phenomenon and increasing the flow rate of the fluid while decreasing the flow volume of the outlet at the outlet of the diffuser and the outlet of the casing to minimize the flow loss of the fluid by increasing the flow rate of the increased flow rate, Reduced cost due to compressor design by enabling compact design of casing In providing the enlarged area to allow compressor operation will be achieved with the purpose.

According to an aspect of the present invention, there is provided a compressor having an expanded operating range, including: a casing having an inlet, an outlet, and a bolt for discharging the compressed fluid to the outside; An impeller positioned within the casing and having a plurality of vanes, the impeller rotating by a rotating shaft to compress fluid entering the inlet; A diffuser provided at an outlet side of the casing; Wherein an entrance flow passage for introducing a cooling element for upwardly moving a minimum operable inlet volumetric flow rate relative to a reference outlet pressure is formed on the inlet side of the casing, and an outlet flow passage is formed in the outlet side of the casing and the diffuser, And an outlet flow path and a diffuser flow path which communicate with each other through which a cooling element for increasing the maximum inlet volumetric flow amount is injected.

The first circulation line is connected to the inlet channel, and the first circulation line is connected to a first supply device for supplying a cooling element to the inlet channel.

The outlet flow path is divided into a first flow path connected in a volute at one end of an outlet side of the casing and a second flow path connected in a volute at the other outlet end side of the casing, As shown in FIG.

The second circulation line is connected to the first flow path and the second flow path, and the second circulation line is connected to a second supply device for supplying cooling elements to the first and second flow paths and the diffuser flow path, respectively Connection.

A second circulation line is connected to the first flow path and the second flow path, and a third supply device for supplying a heat source to the first and second flow paths and the diffuser flow path is connected to the second circulation line .

Further, the cooling element is water or a refrigerant.

As described above, the present invention constitutes a flow path through which a cooling element can flow in a casing inlet side and an outlet side of a compressor, and through which a cooling element is simultaneously or selectively supplied to an inlet side and an outlet side of a compressor casing, It is possible to suppress the surge phenomenon such as flow clogging or reverse flow at the inlet side of the casing by improving the performance to the enlarged operation region in which the minimum inlet volumetric flow rate and the maximum inlet volumetric flow rate can be increased based on the contrast outlet pressure, It is possible to minimize the flow loss of the fluid by decreasing the flow volume of the outlet at the outlet of the diffuser and the outlet of the casing by increasing the flow rate to increase the compression efficiency of the compressor, It is possible to expect the effect of reducing the cost .

On the other hand, according to the present invention, by selectively supplying a heat source to the casing inlet side, the outlet side, and the diffuser as needed, the volume flow rate at the outlet side of the casing can be reduced or a device requiring high- A generator, an air conditioner, an engine, and the like) while improving the operation performance of the apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view showing a structure of a compressor in which an operation region is enlarged according to an embodiment of the present invention. FIG.
FIG. 2 is a schematic cross-sectional view of a state in which a volume flow rate increasing element and a coolant, which is a reducing element, are supplied to an inlet side and an outlet side of a compressor casing, respectively, according to an embodiment of the present invention.
FIG. 3 is a graph comparing the performance curves of the compressor of the present invention in which the conventional compressor and the operation region are enlarged.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic sectional view showing a structure of a compressor in which an operation region is enlarged according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a state where a cooling element is supplied to an inlet side and an outlet side of a compressor casing, Fig.

1 and 2, a compressor A having an enlarged operation region according to an embodiment of the present invention includes an inlet 11 and an outlet 12, and a volute (not shown) for discharging the compressed fluid to the outside 13; < / RTI > An impeller 20 located in the casing 10 and having a plurality of vanes 21 and compressing a fluid which is rotated by the rotary shaft 22 and flows into the inlet 11; And a diffuser 30 provided at an outlet 12 of the casing 10. In order to enlarge the operating range of the compressor A with respect to the inlet 11 of the casing 10, The inlet flow path U1 into which the cooling element for increasing the minimum operable flow volume Qmin to Qmin 'relative to the reference outlet pressure P1 is formed and the outlet 12 of the casing 10 The diffuser 40 connected to the diffuser 40 is provided with an outlet flow passage for introducing the cooling element of water or refrigerant to raise the maximum operable volume flow rate Qmax? Qmax 'relative to the reference outlet pressure P1 as shown in FIG. 3 U2) and a diffuser passage (U3) communicating with the outlet passage (U2).

The first circulation line L1 is connected to the inlet flow path U1 and the first supply device 100 for supplying a cooling element to the inlet flow path U1 is connected to the first circulation line L1, .

The outlet flow path U2 includes a first flow path U21 connected to the outlet 12 side of the casing 10 by a bolt 13 and a second flow path U21 connected to the outlet end 12 of the casing 10, And the second flow path U22 connected to the second flow path U22 and the diffuser flow path U3 are connected to the second flow path U22.

The second circulation line L2 is connected to the first flow path U21 and the second flow path U22 and a cooling element is connected to the first flow path U21 and the second flow path L2, And a second supply device 200 for supplying the second fluid to the second flow path U22, respectively.

Although it has been described that the first circulation line L1 is connected to the first supply device 100 and the second circulation line L2 is connected to the second supply device 200, And the two circulation lines L1 and L2 may be connected to one supply device in a branching manner.

Although not shown in the drawings, the first and second circulation lines L1 and L2 may each be configured to have a valve that is controlled to be opened or closed by a control unit. Depending on whether the valve is opened or closed, 100 and the second feeder 200 to simultaneously supply the cooling elements to the first and second flow paths U21 and U22 included in the inlet flow path U1 and the outlet flow path U1, So that they can be supplied selectively.

1 to 3, the compressor A having an enlarged operation region according to the embodiment of the present invention is formed by forming a vane 21 by a rotating shaft 22 in a casing 10 When the impeller 20 is rotated, fluid is introduced into the inlet 11 of the casing 10 and compressed.

At this time, the first and second flow paths U21 and U22, which are the inlet flow path U1 and the outlet flow path U2 provided on the inlet 11 side and the outlet 12 side of the casing 10, respectively, (100) (200) through the first and second circulation lines (L1, L2), the fluid flowing into the inlet (11) side flows along the inlet flow path (U1) The minimum inlet volumetric flow rate Qmin 'that can be operated by increasing the outlet pressure while being cooled by the circulating cooling element is made upward relative to the reference outlet pressure P1.

That is, when the fluid flowing into the inlet 11 side is cooled by the cooling element flowing along the inlet flow path U1 and the temperature is reduced, the minimum operable inlet volumetric flow rate (Volume flow rate and density are inversely proportional to each other) while increasing the minimum inlet volume flow rate (qmin ') relative to the reference outlet pressure (P1), thereby suppressing the surge phenomenon You can.

The compressed fluid flowing into the inlet 11 of the casing 10 passes through the outlet 12 of the casing 10 and the diffuser 40. The outlet flow path U2 The refrigerant is circulated in the diffuser passage U3 communicated with the second flow path U22 as well as the first and second flow paths U21 and U22 of the diffuser 40. Therefore, The flow rate of the compressed fluid is slowed and the pressure ratio at the outlet 12 side of the casing 10 is increased to increase the maximum operable inlet volumetric flow rate Qmax ' Is made upward relative to the reference outlet pressure P1.

3, the minimum inlet volumetric flow rate Qmin 'and the maximum inlet volumetric flow rate Qmax' at the inlet 11 side of the casing 10 of the compressor A are the same as the minimum inlet flow volume Qmax ' The slope of the improved performance curve D11 of the compressor A of the present invention is relatively larger than the volume flow rate Qmin and the maximum inlet volumetric flow Qmax so that the performance curve D1 of the conventional compressor, Is relatively large.

Therefore, from the change in the minimum inlet volumetric flow rate (Qmin? Qmin ') and the maximum inlet volumetric flow rate (Qmax? Qmax') at the inlet (11) side of the casing (10) The surge locating point b1 of the compressor A according to the example is upward, so that the embodiment of the present invention delays the surging of the minimum inlet volumetric flow rate Qmin to Qmin 'as much as the maximum inlet volumetric flow rate The operating range can be widened by about 10% or more, and the compression efficiency of the compressor (A) is also within a range of about 2 to 5% .

In the embodiment of the present invention, the second circulation line L2 is connected to the first and second flow paths U21 and U22, which are the outlet flow paths U2 provided on the outlet 12 side of the casing 10, respectively A third supply device 300 for supplying a heat source to the second circulation line L2 can be connected and configured.

The supply of the heat source to the diffuser flow path U3 of the diffuser 30 as well as the first flow path U21 and the second flow path U22 may be performed by using the outlet 12 of the casing 10 and the diffuser 30), or by reducing the outlet volumetric flow rate of the fluid when the compressed fluid has passed through it, or by changing the outlet volumetric flow rate of the reduced fluid or the fluid at high temperature and high pressure to the volute (For example, a generator, an air conditioner, an engine, or the like) by supplying a fluid having a reduced outlet flow volume or a high-temperature and high-pressure fluid to the outside .

Although the technical idea of the expanded compressor of the present invention has been described above with reference to the accompanying drawings, it is to be understood that the present invention is by no means restricted to the most preferred embodiments of the present invention.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. It is to be understood that such changes and modifications are within the scope of the claims.

10; Casing 11; Entrance
12; Exit 13; Volute
20; Impeller 21; Vane
22; A rotating shaft 30; defuser
U1; Inlet channel U2; Exit euro
U21; A first flow path U22; The second euros
U3; Diffuser flow

Claims (6)

A casing having an inlet, an outlet, and a bolt for discharging the compressed fluid to the outside; An impeller positioned within the casing and having a plurality of vanes, the impeller rotating by a rotating shaft to compress fluid entering the inlet; A diffuser provided at an outlet side of the casing; , ≪ / RTI &
An inlet flow passage through which a cooling element for introducing a minimum operable flow volume relative to a reference outlet pressure is formed is formed at an inlet side of the casing,
Wherein an outlet passage and a diffuser passage are formed in the outlet of the casing and in the diffuser, the outlet passage and the diffuser passage being communicated with each other for introducing a cooling element for increasing a maximum operable inlet volumetric flow rate relative to a reference outlet pressure, . The refrigeration system of claim 1, wherein the first circulation line is connected to the inlet channel, and the first circulation line is connected to a first supply device for supplying a cooling element to the inlet channel. Compressor. 3. The compressor according to claim 2, wherein the outlet flow path is divided into a first flow path connected by a bolus at one end of an outlet side of the casing and a second flow path connected by a bolus at the other outlet end side of the casing, And the second flow path is communicated with the second flow path. The apparatus according to claim 3, wherein the first circulation line is connected to the first circulation line and the second circulation line is connected to the second circulation line, and the second circulation line is connected to the first circulation line and the second circulation line, And the supply device is connected to the compressor. The apparatus of claim 3, wherein the first circulation line is connected to the first circulation line and the second circulation line is connected to the second circulation line, and the third circulation line is connected to the third circulation line, And the supply device is connected to the compressor. 5. The compressor of claim 4, wherein the cooling element is water or refrigerant.

Images