A double-layer casing flow channel diversion and support structure

Abstract

The present invention discloses a double-layer casing flow channel diversion and support structure, which includes a diversion and support structure body. The diversion and support structure body is in a cylindrical shape. The inlet end of the diversion and support structure body is connected to the outlet end of the inner casing, and the inner casing is communicated with the pump outlet of the pump unit through the diversion and support structure body. A plurality of ear plates are circumferentially and uniformly distributed on the diversion and support structure body, and the diversion and support structure body is connected to the outer casing through the ear plates. A diversion device is provided on the ear plates, and the diversion device is located between the inner casing and the outer casing. The diversion direction of the diversion device is the same as the water flow direction. By adopting this solution, the outer casing and the inner casing are connected through the diversion and support structure, thereby forming a stable support structure, improving the structural stability of the inner casing, and improving the flow pattern of the pump inlet flow field through the diversion effect of the diversion device, and improving the hydraulic performance of the pump.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-purpose modular small reactors, and specifically relates to a double-layer casing flow channel diversion and support structure. Background Art

[0002] In fields such as multi-purpose modular small reactors, pump units such as reactor coolant pumps are installed in a double-layer casing flow channel, that is, all or part of the pump hydraulic structure is placed in the system pipeline. The pipeline serves as the pump casing or a part of the pump casing. The annular cavity between the outer casing and the inner casing is connected to the pump inlet as the pump inlet flow channel, and the inner casing is connected to the pump outlet as the pump outlet flow channel. This layout is structurally compact and is conducive to the miniaturization of the system and equipment.

[0003] However, under this layout, since the double-layer casing flow channel is not a diversion structure specifically designed according to the pump hydraulic performance, the flow field at the pump inlet is disordered; and the support structure of the inner casing needs to be connected to the outer casing, which will further disrupt the pump inlet flow field and reduce the pump hydraulic performance. To reduce the disturbance of the support structure to the flow field, the volume of the support structure should be reduced, which is not conducive to the stability of the inner casing. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that in fields such as multi-purpose modular small reactors, due to structural limitations, the pump hydraulic performance installed in the double-layer casing flow channel is low, and the support strength of the inner casing is small. The purpose is to provide a double-layer casing flow channel diversion and support structure. By adopting this solution, the flow field characteristics at the pump inlet are improved, the structural strength of the inner casing support is increased, and the fluid after the pump outlet is guided.

[0005] The present invention is achieved by the following technical solutions:

[0006] A double-layer casing flow channel diversion and support structure includes a diversion and support structure body;

[0007] The diversion and support structure body is in a cylindrical shape. The inlet end of the diversion and support structure body is connected to the outlet end of the inner casing, and the inner casing is communicated with the pump outlet of the pump unit through the diversion and support structure body;

[0008] A number of lugs are circumferentially and evenly distributed on the diversion and support structure body, and the diversion and support structure body is connected to the outer casing through the lugs;

[0009] A diversion device is provided on the lug, and the diversion device is located between the inner casing and the outer casing; the diversion direction of the diversion device is the same as the water flow direction.

[0010] Compared with the prior art, in the fields of multi-purpose modular small reactors and others, due to structural limitations, there are problems such as low hydraulic performance of pumps installed in double-layer casing flow channels and small support strength of the inner casing. This solution provides a double-layer casing flow channel diversion and support structure. By adopting this solution, the outer casing and the inner casing are connected through the diversion and support structure, thus forming a stable support structure, improving the structural stability of the inner casing, and through the diversion effect of the diversion device, improving the flow pattern of the pump inlet flow field and enhancing the hydraulic performance of the pump. In a specific solution, the pump unit body is installed on the upper flange surface of the double-layer casing through main bolts. A diversion and support structure body is provided on the outer casing and the inner casing. The diversion and support structure body is cylindrical. At its inlet end, that is, the lower end, it is fixedly connected to the outlet end of the inner casing and is in communication with the inside of the inner casing. The upper end of the diversion and support structure body cooperates with the pump unit, so that the inside of the diversion and support structure body constitutes the pump outlet channel. A number of evenly distributed ear plates extend outward in the circumferential direction of the diversion and support structure body. The diversion and support structure body is fixedly connected to the outer casing through the ear plates, thus connecting the inner casing and the outer casing and improving the structural stability of the inner casing. At this time, the pump inlet guide vane cooperates with the diversion and support structure, so that the area between the outer casing and the inner casing and the outside of the diversion and support structure constitutes the pump inlet diversion area.

[0011] As described above, further, since the position where the double-layer casing is connected to the pump unit is a bent pipe, the incoming water flow between the outer casing and the inner casing is disordered, thus disturbing the pump inlet flow field and reducing the hydraulic performance of the pump. Therefore, in this solution, a diversion device is provided on the ear plate. The diversion direction of the diversion device is the same as the water flow direction, which is convenient for diverting the water flow between the outer casing and the inner casing, thus improving the characteristics of the pump inlet flow field and enhancing the hydraulic performance of the pump.

[0012] For further optimization, the diversion device is a diversion cone. The bottom of the diversion cone is connected to the side of the ear plate far from the pump unit, and the top of the diversion cone extends in a direction away from the ear plate. Since the diversion device is arranged in the interlayer between the outer casing and the inner casing, in order to adapt to the assembly dimensions between the outer casing and the inner casing, this solution selects a diversion cone. The diversion cone is arranged on the ear plate and is located below the ear plate, and its top extends downward. While diverting the incoming water, it can also reduce the local disturbance of the water flow caused by the ear plate.

[0013] For further optimization, the flow guiding cone is in the shape of a triangular prism, and the width direction of the flow guiding cone is arranged along the length direction of the ear; to reduce the disorder phenomenon of the water flow caused by the ear, in this solution, the flow guiding cone is in the shape of a triangular prism, and its width direction is the same as the length direction of the ear. By widening the flow guiding cone, the guiding effect on the water flow can be improved, and the influence of the ear on the water flow can be reduced; it can be preferably arranged along the radial direction of the flow guiding support structure body; the flow guiding cone is clamped between the outer sleeve and the inner sleeve, and there is a certain assembly gap for easy disassembly.

[0014] For further optimization, the width of the side surface at the bottom of the flow guiding cone is equal to the width of the ear; to prevent the disorder phenomenon of the water flow caused by the ear, in this solution, if the width of the bottom of the flow guiding cone is smaller than the width of the ear, it will form a resistance to the water flow, and if the width of the bottom of the flow guiding cone is larger than the width of the ear, an eddy current will be formed on the back, both of which are not conducive to guiding. Therefore, the width of the side surface at the bottom of the flow guiding cone needs to be equal to the width of the ear.

[0015] For further optimization, the top of the flow guiding cone is a smooth curved surface; used to improve the guiding effect.

[0016] For further optimization, the flow guiding cone and the ear are integrally formed; used to improve the connection strength of the flow guiding cone, and the connection method can also be fixed connection methods such as welding.

[0017] For further optimization, the side of the ear close to the pump unit is a flat structure; by setting the upper side of the ear as a plane, it is convenient to cooperate with the pump unit.

[0018] For further optimization, the flow guiding support structure body and the inner sleeve are coaxially arranged.

[0019] For further optimization, an inner cylinder is provided at the inlet end of the flow guiding support structure body, the inner diameter of the inner cylinder is adapted to the inner diameter of the inner sleeve, and the end of the inner cylinder is welded to the end of the inner sleeve; to improve the stability of the flow guiding support structure and avoid vibration, in this solution, an inner cylinder connected to the inner sleeve is provided at the inlet end of the flow guiding support structure body. The inner diameter and wall thickness of the inner cylinder are the same as those of the inner sleeve, and they are connected by welding, thereby improving the connection strength; the inner cylinder and the inner pipeline together form a fluid channel after the pump outlet, so as to collect and guide the fluid leaving the pump.

[0020] For further optimization, a stepped hole is provided in the outer sleeve, the ear extends into the step of the stepped hole, and is connected to the step by bolts; to achieve the detachable of the flow guiding support structure body, in this solution, a through hole is provided at the end of the ear, and a threaded hole is provided on the step of the stepped hole. At this time, the detachable connection between the ear and the outer sleeve can be realized by bolts.

[0021] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0022] 1. The present invention provides a double-layer casing flow channel diversion and support structure, which, together with the diversion device and the inner casing, plays a role in diverting the fluid after the pump outlet, improves the flow pattern of the pump inlet flow field, and enhances the hydraulic performance of the pump; moreover, this structure can improve the support structure strength of the inner casing and enhance the stability of the inner casing.

[0023] 2. The present invention provides a double-layer casing flow channel diversion and support structure, which redesigns the support structure of the inner casing of the double-layer casing flow channel by changing the structural dimensions of the support of the inner casing of the double-layer casing flow channel according to the structure conducive to flow field stability, and improves the strength of this support structure.

[0024] 3. The present invention provides a double-layer casing flow channel diversion and support structure, which is applicable to the diversion and support structure of double-layer casing flow channels in fields such as multi-purpose modular small reactors, etc., to solve the single-core technical bottleneck of double-layer casing flow channels, improve the hydraulic performance of the pump used for double-layer casing flow channels, and enhance the structural stability of the inner casing. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts. In the drawings:

[0026] Figure 1 is a schematic structural diagram of the overall layout provided by the present invention;

[0027] Figure 2 is a partial schematic diagram A-A provided by the present invention;

[0028] Figure 3 is a schematic structural diagram of the diversion and support structure body provided by the present invention;

[0029] Figure 4 is a sectional view B-B of the diversion cone provided by the present invention.

[0030] Reference numerals in the drawings and corresponding component names:

[0031] 1 - double-layer casing, 2 - pump unit, 3 - outer casing, 4 - inner casing, 5 - diversion and support structure body, 51 - ear, 52 - diversion device, 53 - inner cylinder, 6 - bolt. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] To make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to embodiments and the accompanying drawings. The illustrative embodiments and descriptions thereof of the present invention are only used to explain the present invention and shall not be construed as limiting the present invention. Embodiment

[0033] As Figures 1 to 4 shown, this embodiment provides a double-layer casing flow channel diversion and support structure, including a diversion and support structure body 5;

[0034] The diversion and support structure body 5 is in a cylindrical shape. The inlet end of the diversion and support structure body 5 is connected to the outlet end of the inner casing 4, and the inner casing 4 is communicated with the pump outlet of the pump unit 2 through the diversion and support structure body 5;

[0035] A number of lugs 51 are circumferentially and uniformly distributed on the diversion and support structure body 5. The diversion and support structure body 5 is connected to the outer casing 3 through the lugs 51;

[0036] A diversion device 52 is provided on the lug 51. The diversion device 52 is located between the inner casing 4 and the outer casing 3; the diversion direction of the diversion device 52 is the direction of the water flow.

[0037] Compared with the prior art, in the fields of multi-purpose modular small reactors, etc., due to structural limitations, the pump hydraulic performance installed in the flow channel of the double-layer casing 1 is low, and the support strength of the inner casing 4 is small. This solution provides a double-layer casing 1 flow channel diversion and support structure. By adopting this solution, the outer casing 3 and the inner casing 4 are connected through the diversion and support structure, thereby forming a stable support structure, improving the structural stability of the inner casing 4, and improving the pump inlet flow field flow pattern and the pump hydraulic performance through the diversion effect of the diversion device 52; in the specific solution, the pump unit 2 body is installed on the upper flange surface of the double-layer casing 1 through main bolts, and the diversion and support structure body 5 is arranged on the outer casing 3 and the inner casing 4. The diversion and support structure body 5 is in a cylindrical shape. Its inlet end, that is, the lower end, is fixedly connected to the outlet end of the inner casing 4 and is internally communicated with the inner casing 4, while the upper end of the diversion and support structure body 5 cooperates with the pump unit 2, so that the inside of the diversion and support structure body 5 forms a pump outlet channel; a number of uniformly distributed lugs 51 extend outward in the circumferential direction of the diversion and support structure body 5. The diversion and support structure body 5 is fixedly connected to the outer casing 3 through the lugs 51, so that the inner casing 4 and the outer casing 3 are connected, improving the structural stability of the inner casing 4. At this time, the pump inlet guide vane cooperates with the diversion and support structure, so that a pump inlet diversion area is formed between the outer casing 3 and the inner casing 4 and outside the diversion and support structure.

[0038] As described above, further, since the position where the double-layer casing 1 is connected to the pump unit 2 is a bent pipe, the water inflow between the outer casing 3 and the inner casing 4 is disordered, thus disturbing the inlet flow field of the pump and reducing the hydraulic performance of the pump. Therefore, in this solution, a flow guiding device 52 is provided on the support ear 51. The flow guiding direction of the flow guiding device 52 is the same as the water flow direction, which is convenient for guiding the water flow between the outer casing 3 and the inner casing 4, thereby improving the characteristics of the pump inlet flow field and enhancing the hydraulic performance of the pump.

[0039] Please refer to Figure 3 , in this embodiment, as a specific implementation manner for reducing the influence of the support ear 51 on the water flow, it is set that: the flow guiding device 52 is a flow guiding cone. The bottom of the flow guiding cone is connected to the side of the support ear 51 away from the pump unit 2, and the top of the flow guiding cone extends in a direction away from the support ear 51; since the flow guiding device 52 is arranged in the interlayer between the outer casing 3 and the inner casing 4, in order to adapt to the assembly dimensions between the outer casing 3 and the inner casing 4, this solution selects a flow guiding cone. The flow guiding cone is arranged on the support ear 51 and is located below the support ear 51, and its top extends downward. While guiding the inlet water flow, it can also reduce the local disturbance of the water flow caused by the support ear 51.

[0040] For the above solution, further, please refer to Figure 3 and Figure 4 , as a specific implementation manner for reducing the disorder phenomenon of the water flow caused by the support ear 51, it is set that: the flow guiding cone is in a triangular prism shape, and the width direction of the flow guiding cone is arranged along the length direction of the support ear 51; in this solution, the flow guiding cone is in a triangular prism shape, and its width direction is the same as the length direction of the support ear 51. By widening the flow guiding cone, the flow guiding effect on the water flow can be improved, and the influence of the support ear 51 on the water flow can be reduced; it can be preferably arranged along the radial direction of the flow guiding support structure body 5; wherein the flow guiding cone is clamped between the outer casing 3 and the inner casing 4, and a certain assembly gap is left for easy disassembly.

[0041] Please continue to refer to Figure 3 , in the above solution, if the width of the bottom of the flow guiding cone is smaller than the width of the support ear 51, it will form a resistance to the water flow, and if the width of the bottom of the flow guiding cone is larger than the width of the support ear 51, a vortex will be formed on the back. Both of these methods are not conducive to flow guiding. Therefore, in this embodiment, it is set that: the width of the side surface of the bottom of the flow guiding cone is equal to the width of the support ear 51; this is used to prevent the support ear 51 from causing a disorder phenomenon to the water flow.

[0042] Please refer to Figure 4 , as a specific implementation manner for enhancing the flow guiding effect, it is set that: the top of the flow guiding cone is a smooth curved surface.

[0043] As a specific implementation for improving the connection strength of the flow guide cone, it is set that the flow guide cone and the lug 51 are integrally formed; the connection method can also be a fixed connection method such as welding, which will not be elaborated here.

[0044] In this embodiment, the side of the lug 51 close to the pump unit 2 is a planar structure; by setting the upper side of the lug 51 as a plane, it is convenient to cooperate with the pump unit 2.

[0045] In this embodiment, the flow guide support structure body 5 and the inner casing 4 are coaxially arranged.

[0046] Please refer to Figure 1 and Figure 3 , as a specific implementation for improving the stability of the flow guide support structure and avoiding vibration, it is set that an inner cylinder 53 is provided at the inlet end of the flow guide support structure body 5, the inner diameter of the inner cylinder 53 is adapted to the inner diameter of the inner casing 4, and the end of the inner cylinder 53 is welded to the end of the inner casing 4; in this solution, an inner cylinder 53 connected to the inner casing 4 is provided at the inlet end of the flow guide support structure body 5, the inner diameter and wall thickness of the inner cylinder 53 are the same as those of the inner casing 4, and they are connected by welding, so as to improve the connection strength; the inner cylinder 53 and the inner pipeline together form a fluid channel after the pump outlet, so as to collect and guide the fluid leaving the pump.

[0047] As a specific implementation for realizing the detachable of the flow guide support structure body 5, it is set that a stepped hole is provided in the outer casing 3, the lug 51 extends into the step of the stepped hole, and is connected to the step by a bolt 6; in this solution, a through hole is provided at the end of the lug 51, and a threaded hole is provided on the step of the stepped hole. At this time, the detachable connection between the lug 51 and the outer casing 3 can be realized by the bolt 6.

[0048] Specific working principle: During equipment installation, the inner casing 4 is connected and fixed through the flow guide support structure body 5 and the outer casing 3, and the accuracy of centering is ensured by the manufacturing precision of the flow guide support structure body 5 and the inner casing 4; the pump unit 2 body is installed on the upper flange surface of the double-layer casing 1 through the main bolt, and the pump inlet guide vane cooperates with the flow guide support structure body 5 to form a pump inlet flow guide area. When the pump is running, the fluid flows from the interlayer between the outer casing 3 and the inner casing 4 to the inlet of the pump. After being guided by the flow guide cone on the flow guide support structure body 5, a relatively stable fluid enters the pump, and after obtaining the energy transmitted by the pump, it enters the outlet flow channel formed by the flow guide support structure body 5 and the inner casing 4. The above structure connects the outer casing 3 and the inner casing 4 through the flow guide support structure, thereby forming a stable support structure, improving the structural stability of the inner casing 4, and improving the flow pattern of the pump inlet flow field and the hydraulic performance of the pump through the guiding action of the flow guiding device 52.

[0049] The specific embodiments described above further elaborate on the object, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A double-layer casing flow channel diversion and support structure, characterized in that It includes a diversion support structure body (5); The diversion support structure body (5) is cylindrical. The inlet end of the diversion support structure body (5) is connected to the outlet end of the inner sleeve (4), and the inner sleeve (4) is communicated with the pump outlet of the pump unit (2) through the diversion support structure body (5); A number of lugs (51) are circumferentially and evenly distributed on the diversion support structure body (5), and the diversion support structure body (5) is connected to the outer sleeve (3) through the lugs (51); A diversion device (52) is provided on the lug (51), and the diversion device (52) is located between the inner sleeve (4) and the outer sleeve (3); the diversion direction of the diversion device (52) is the direction of the flowing water; The diversion device (52) is a diversion cone. The bottom of the diversion cone is connected to the side of the lug (51) away from the pump unit (2), and the top of the diversion cone extends in a direction away from the lug (51); The diversion cone is in the shape of a triangular prism, and the width direction of the diversion cone is arranged along the length direction of the lug (51); The width of the side surface at the bottom of the diversion cone is equal to the width of the lug (51); An inner cylinder (53) is provided at the inlet end of the diversion support structure body (5). The inner diameter of the inner cylinder (53) is adapted to the inner diameter of the inner sleeve (4), and the end of the inner cylinder (53) is welded to the end of the inner sleeve (4).

2. The double-layer casing flow channel diversion and support structure according to claim 1, characterized in that, The top of the diversion cone is a smooth curved surface.

3. A double-layer casing flow channel diversion and support structure according to claim 1, characterized in that, The diversion cone and the lug (51) are integrally formed.

4. A double-layer casing flow channel diversion and support structure according to claim 1, characterized in that, The side of the lug (51) close to the pump unit (2) is a planar structure.

5. A double-layer casing flow channel diversion and support structure according to claim 1, characterized in that, The diversion support structure body (5) and the inner sleeve (4) are coaxially arranged.

6. The double-layer casing flow channel diversion and support structure according to claim 1, wherein, The outer sleeve (3) is provided with a stepped hole. The lug (51) extends into the step of the stepped hole and is connected to the step through a bolt (6).

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