CN220912069U - Self-supporting bayonet pipe and heat exchanger - Google Patents

Abstract

The utility model relates to the technical field of bayonet pipes, and discloses a self-supporting bayonet pipe and a heat exchanger. The inner tube is coaxially arranged in the outer tube, and an annular gap is arranged between the inner tube and the outer tube. The support member is disposed within the annular gap and maintains the coaxiality of the outer tube and the inner tube during heat exchange. The support extends radially of the annular gap and the ends of the support are provided with a tree-like bifurcation structure. The utility model can keep the coaxiality of the inner tube and the outer tube, resist the influence of the flow of the internal heat exchange medium and the external organic working medium in the heat exchange process, reduce the vibration and the deformation under the high-temperature condition, thereby ensuring the heat exchange effect and the service life. On the basis, the supporting piece can strengthen the turbulence effect in the annular gap, so that the heat transfer effect is enhanced.

Description

Self-supporting bayonet pipe and heat exchanger

Technical Field

The utility model relates to the technical field of bayonet tubes, in particular to a self-supporting bayonet tube and a heat exchanger.

Background

The current development of waste heat resources faces a number of challenges such as volatility, instability, insufficient peak shaving capacity, etc. The waste heat at medium and low temperature (lower than 350 ℃) is generally regarded as low-grade energy, and the waste heat is difficult to be effectively utilized by the traditional Rankine cycle power generation taking water as working medium. Compared with the traditional Rankine cycle power generation, the organic Rankine cycle power generation utilizes low-boiling point organic matters as working media, converts low-grade energy into high-grade energy such as electric energy and the like, reduces the requirement on temperature, and can improve the power generation efficiency and the power generation capacity.

In the organic Rankine cycle power generation process, a heat exchanger is required to provide heat for an organic working medium, so that organic vapor is generated to drive an expander/a steam turbine to rotate, and a generator is driven to generate power. The bayonet tube type heat exchanger breaks through the columnar flowing state of tube side working medium in the traditional tube shell type heat exchanger, and is an efficient heat exchanger.

The free end of the traditional bayonet tube heat exchanger is a cantilever type heat exchange tube, for example, in Chinese patent application with publication number of CN116007411A, an ultra-high temperature high pressure bayonet tube heat exchanger is disclosed, an outer tube of the bayonet tube is arranged outside an inner tube, a gap is reserved between the outer tube and the inner tube, however, the bayonet tube is generally vertically placed in the use process, the vibration problem caused by high-speed fluid movement in the equipment operation process is difficult to avoid, and particularly, the inner tube in the bayonet tube is small in general diameter, is easy to damage and deform due to vibration and high temperature conditions, and influences the service life. In addition, the boiling heat exchange coefficient is larger than the condensation heat exchange coefficient, and the efficiency of the traditional bayonet tube heat exchanger under the working condition of shell side evaporation-tube side condensation operation is reduced.

Disclosure of utility model

In order to avoid and overcome the technical problems in the prior art, the utility model provides the self-supporting bayonet tube and the heat exchanger, which can provide supporting and protecting effects for the inner tube in the bayonet tube, thereby reducing the vibration of the inner tube and the deformation under the high-temperature condition, and guaranteeing the heat exchange effect and the service life.

In order to achieve the above purpose, the present utility model provides the following technical solutions:

The utility model discloses a self-supporting bayonet pipe which comprises an outer pipe, an inner pipe coaxially arranged in the outer pipe, an annular gap arranged between the outer pipe and the inner pipe, and a supporting piece arranged in the annular gap and used for keeping coaxiality of the outer pipe and the inner pipe in the heat exchange process. The support extends along the radial direction of the annular gap, and the support is provided with a tree-shaped bifurcation structure along the extending direction.

As a further improvement of the above solution, the tree-like bifurcation structure has a plurality of bifurcation ends. The outer edge of each bifurcated end is contoured to conform to the outer or inner tube with which it is in contact and forms a diverging passageway in the annular gap parallel to the axis of the annular gap.

As a further improvement of the above solution, the support member is provided with the tree-like bifurcation structure at both ends or at either end in the direction of extension of the support member.

As a further improvement of the above, the support is provided with a plurality of spaced-apart around the circumference of the annular gap.

And/or the support piece is provided with a plurality of spaced-apart along the axial direction of the annular gap.

As a further improvement of the above, one of the outer tube and the inner tube is fixedly connected to the support member, and the other is in contact with the support member but not fixed thereto.

Or the outer tube and the inner tube are fixedly connected with the supporting piece.

As a further development of the above, the outer tube and/or the inner tube is fixedly connected to the support by means of any one of the following forms: integrated into one piece, welding and buckle formula connection.

As a further improvement of the above scheme, one end of the outer tube is a closed end, and the other end is an open end. One end of the inner tube extends into the outer tube from the opening end of the outer tube, and a space is reserved between the inner tube and the closed end of the outer tube, so that the cavity of the inner tube is communicated with the annular gap. Wherein, the cavity of inner tube is said one end far away from closed end is steam inlet, the one end far away from closed end of annular gap is condensation outlet.

The utility model also discloses a heat exchanger, which comprises a shell and a bayonet tube arranged in the shell and used for providing heat for working media in the shell, wherein the bayonet tube is any one of the self-supporting bayonet tubes.

As a further improvement of the above solution, the bayonet pipes are provided with a plurality of groups, and the extending directions of the plurality of groups of bayonet pipes are all parallel to the extending direction of the housing.

As a further improvement of the above, the heat exchanger further comprises a grille for mounting within the housing and for securing the bayonet tube.

Compared with the prior art, the utility model has the beneficial effects that:

1. According to the utility model, the support piece is arranged in the annular gap between the outer tube and the inner tube of the bayonet tube, so that the coaxiality of the inner tube and the outer tube can be kept, the end part of the support piece is provided with the tree-shaped bifurcation structure with an increased contact area, the tree-shaped bifurcation structure can also provide a buffer effect when the inner tube generates radial load, the influence of the flow of an internal heat exchange medium and an external organic working medium is resisted in the heat exchange process, and the deformation under the conditions of vibration and high temperature is reduced, so that the heat exchange effect and the service life are ensured. On the basis, the supporting piece and the tree-shaped bifurcation of the supporting piece can strengthen the turbulence effect in the annular gap, so that the shell side evaporation-tube side condensation operation efficiency is improved.

2. According to the utility model, the arrangement mode and the number of the supporting pieces in the circumferential direction and the axial direction can be adaptively set according to practical application requirements, and the connection objects and the connection modes of the supporting pieces in the annular gap can be set, so that the disassembly and assembly difficulty of the bayonet tube and the heat exchanger is reduced, the supporting effect of the supporting pieces is regulated, and the compatibility and the universality of the supporting pieces are ensured.

3. By applying the supporting piece, the heat exchanger has partial beneficial effects which are the same as those of the bayonet pipe. On the basis, through setting up the grid that is used for fixed bayonet pipe outer tube in the heat exchange shell side to vibration and the deformation of outer tube can be reduced, heat transfer effect and life have further been ensured.

Drawings

FIG. 1 is a schematic view of a heat exchanger according to a preferred embodiment of the present utility model, in which only one group of heat exchange tubes is disposed in a housing;

FIG. 2 is a schematic diagram showing an arrangement of a plurality of heat exchange tubes according to a preferred embodiment of the present utility model;

FIG. 3 is a schematic top view of the grille of FIG. 2;

FIG. 4 is a schematic cross-sectional view of the relative positions of the outer tube and the inner tube of the bayonet of the present utility model;

FIG. 5 is a schematic perspective view of a bayonet tube according to a preferred embodiment of the present utility model;

FIG. 6 is a schematic top view of the bayonet tube of FIG. 5;

FIG. 7 is a schematic top view of a tree-like bifurcation structure according to an embodiment of the present utility model, when the support member is disposed near one end of the inner tube;

FIG. 8 is a schematic top view of a tree-like bifurcation structure according to an embodiment of the present utility model;

FIG. 9 is a schematic perspective view of the support member according to a preferred embodiment of the present utility model in an arrangement along the axial direction;

FIG. 10 is a schematic view of an in-vitro structure of a support member according to another embodiment of the present utility model in an axial direction;

FIG. 11 is an enlarged view of a portion of a support member according to a preferred embodiment of the present utility model.

Reference numerals: 10. a bayonet tube; 101. an outer tube; 1010. a closed end; 102. an inner tube; 103. an annular gap; 104. a support; 1040. a tree-like bifurcation structure; 10401. a bifurcation end; 105. a vapor inlet; 106. a condensation outlet; 20. a housing; 301. a grille; 3011. a first pull rod; 3012. a second pull rod; 3013. an outer ring; 30130. a notch; 302. an anti-impact rod; 303. a slide rail; 304. a tube sheet.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Referring to fig. 1, the present embodiment provides a heat exchanger including a bayonet 10, a housing 20, and a grill 301. The bayonet 10 is disposed within the housing 20 and is configured to provide heat to a working fluid within the housing 20. The bayonet 10 of the present utility model is a modified self-supporting bayonet 10, as will be described in greater detail below.

Referring to fig. 2 and 3, in some embodiments, the bayonet 10 may be provided with multiple groups, and the extending directions of the multiple groups of bayonet 10 are parallel to the extending direction of the housing 20. Generally, the heat exchanger may be in a column shape, the liquid low boiling point organic working medium is input to the shell side inlet near the bottom of the shell 20, and is heated by the heat exchanger, and is discharged from the shell side outlet near the top of the shell 20 after the organic working medium is gasified and ascended. Therefore, the multiple groups of bayonet tubes 10 can be square, round or other shapes which are beneficial to the circulation of working medium in cross section, the axes are parallel to the axes of the shell 20, and the heights and the lengths of the multiple groups of bayonet tubes 10 are the same.

The grids 301 can be provided with a plurality of intervals along the axial direction of the shell 20, each grid 301 is provided with a hole site for the bayonet tube 10 to penetrate, and the grids 301 are fixedly arranged inside the shell 20, so that the outer part of the bayonet tube 10 is not easy to vibrate and deform in the heat exchange process. Specifically, the grille 301 may be composed of a first pull rod 3011, a second pull rod 3012 and an outer ring 3013, where the first pull rod 3011 and the second pull rod 3012 are provided with a plurality of holes and are staggered with each other to form a hole site for the bayonet 10 to penetrate. The edges of the first pull rod 3011 and the second pull rod 3012 can be fixedly connected to the inner ring of the outer ring 3013 in a welding mode or the like. The outer ring of the outer ring 3013 can be provided with a notch 30130 with a cross-sectional shape matched with that of the sliding rail 303, the outer ring 3013 can be assembled on the sliding rail 303 through the notch 30130, and a plurality of grids 301 can be fixed in a welding mode.

In addition, the ends (bottom ends in this embodiment) of the multiple sets of bayonet tubes 10 may be secured to one tube sheet 304 by welding, and at least one anti-impingement rod 302 may be welded between the tube sheet 304 and the nearest grid 301, the anti-impingement rod 302 being configured to resist the impact of liquid hydrocarbon (i.e., working fluid) flow changes on the bayonet tubes 10.

Referring to fig. 4 and 5, the bayonet 10 includes an outer tube 101, an inner tube 102, and a support 104.

The inner tube 102 is coaxially arranged within the outer tube 101 with an annular gap 103 therebetween. Wherein one end of the outer tube 101 is a closed end 1010 and the other end is an open end. One end of the inner tube 102 extends from the open end into the outer tube 101 and is spaced from the closed end 1010 of the outer tube 101 to allow the lumen of the inner tube 102 to communicate with the annular gap 103. Wherein the end of the channel away from the closed end 1010 is the vapor inlet 105, and the end of the annular gap 103 away from the closed end 1010 is the condensation outlet 106. In this way, the bayonet 10 forms a back flow tube side, the medium and low temperature waste heat can heat the liquid water and form high temperature vapor, the high temperature vapor is input from the vapor inlet 105, and after the heat transfer by condensation of the back flow tube side, the vapor is discharged from the condensation outlet 106, and in the process, the heat transfer is carried out to the shell side, namely the working medium in the shell 20, and the low boiling point organic working medium is evaporated.

The support 104 is disposed in the annular gap 103, on the one hand, the coaxiality of the outer tube 101 and the inner tube 102 is maintained during heat exchange, on the other hand, water vapor enters the lower end of the inner tube 102 from the vapor inlet 105, flows from bottom to top, enters the annular gap 103 from the upper end of the inner tube 102, flows from top to bottom in the annular gap 103, increases turbulence with the shell of the support 104, enhances condensation heat transfer, and finally is discharged from the lower end of the annular gap 103, namely the condensation outlet 106.

Referring to fig. 6, the support 104 extends along the radial direction of the annular gap 103, and the end of the support 104 is provided with a tree-like bifurcation 1040. In this embodiment, the support 104 is disposed near one end of the outer tube 101 with a tree-shaped bifurcation structure 1040, that is, each bifurcation end 10401 of the tree-shaped bifurcation structure 1040 contacts the outer tube 101, and the outer edge of each bifurcation end 10401 coincides with the inner wall of the outer tube 101 and forms a dispersion channel parallel to the axis of the annular gap 103 in the annular gap 103. These dispersion channels are independent of each other and part of the water vapor will pass through the dispersion channels of the annular gap 103, further enhancing the turbulence effect.

Referring to fig. 7 and 8, in some embodiments, a tree-shaped bifurcation structure 1040 may be disposed at one end of the supporting member 104 near the inner tube 102, and tree-shaped bifurcation structures 1040 may be disposed at two ends of the supporting member 104, respectively, so as to increase the contact area between the supporting member 104 and the outer tube 101 and the contact area between the supporting member and the inner tube 102, and improve the supporting strength of the outer tube 101 to the inner tube 102.

In this embodiment, the number of the supporting members 104 is four, six or other, which are distributed at intervals around the circumference of the annular gap 103, and these supporting members 104 may be distributed at equal intervals in the circumferential direction, so that the supporting strength of the outer tube 101 to the inner tube 102 is further improved, the stability of the inner tube 102 in the radial direction can be enhanced by the equidistant distribution, and vibration or shaking is not easy to occur.

Referring to fig. 9, in this embodiment, the axial length of the support member 104 and the length of the inner tube 102 extending into the outer tube 101 may be matched.

Of course, referring to fig. 10, in some embodiments, the support 104 is provided with a plurality of spaced apart along the axial direction of the annular gap 103. The plurality of supporting members 104 in the same plane (i.e., at the same height) perpendicular to the axis of the inner tube 102 are a supporting group, and the plurality of supporting groups are arranged at intervals, so that the manufacturing material of the bayonet 10 can be saved, and the weight of the bayonet 10 can be reduced. In addition, the projections of the plurality of support groups in the axial direction can be staggered, even in spiral arrangement (similar to the arrangement of the existing stirring blades on the stirring shaft), so that the disturbance effect on the steam flowing in the annular gap 103 can be further enhanced, and the condensing and heat transfer effects are improved.

In the present embodiment, one of the outer tube 101 and the inner tube 102 is fixedly connected to the support 104, and the other is in contact with the support 104 but not fixed, thereby facilitating the disassembly and assembly of the outer tube 101 and the inner tube 102.

In some embodiments, both the outer tube 101 and the inner tube 102 may be fixedly connected with the support 104. In addition, the outer tube 101 and/or the inner tube 102 and the support 104 may be fixedly connected by any one of the following forms: integrally formed, welded or snap-fit. Since the outer tube 101, the inner tube 102 and the supporting member 104 are generally made of metal materials which are favorable for heat conduction, the three connection modes are suitable, and other connection modes can be adopted as long as the structural strength and the air tightness of the outer tube 101, the inner tube 102 and the supporting member 104 are not affected. Specifically, the above three connection forms have the following advantages, respectively.

A. By integrally casting or integrally 3D printing the outer tube 101 and the inner tube 102 and the support 104, the structural strength of the bayonet 10 as a whole may be significantly enhanced.

B. By welding the support 104 to the outer tube 101 and/or the inner tube 102, this facilitates selective placement of the support 104 in the type and arrangement according to actual production requirements.

C. the support 104 is detachably mounted on the outer tube 101 and/or the inner tube 102 by means of a buckle or a slot, etc., so that the inner structure of the bayonet tube 10 can be conveniently detached and cleaned at a later stage.

Referring to fig. 11, the tree-shaped bifurcation structure 1040 of the present utility model has a plurality of bifurcation ends 10401, and the number of bifurcation ends 10401 can be preferably two or three. The outer edge of the bifurcated end 10401 is contoured to conform to the outer tube 101 or the inner tube 102 with which it is in contact. In some embodiments, rounded corners may be provided at the edges or corners of the tree-like furcation structure 1040, which may reduce stress and increase structural strength on the one hand, and may reduce snagging of the outer tube 101 or the inner tube 102 by the edges on the other hand, which may extend the useful life of the bayonet tube 10.

The foregoing is only a preferred embodiment of the present utility model, but the scope of the present utility model is not limited thereto, and any person skilled in the art, who is within the scope of the present utility model, should make equivalent substitutions or modifications according to the technical scheme of the present utility model and the inventive concept thereof, and should be covered by the scope of the present utility model.

Claims (10)

1. The self-supporting bayonet pipe comprises an outer pipe (101) and an inner pipe (102) coaxially arranged in the outer pipe (101), wherein an annular gap (103) is arranged between the outer pipe and the inner pipe, and the self-supporting bayonet pipe is characterized by further comprising a supporting piece (104) which is arranged in the annular gap (103) and used for keeping coaxiality of the outer pipe (101) and the inner pipe (102) in the heat exchange process; the support (104) extends in the radial direction of the annular gap (103), and the support (104) is provided with a tree-like bifurcation structure (1040) in the extending direction.

2. A self-supporting bayonet tube according to claim 1, characterized in that said tree-like bifurcation structure (1040) has a plurality of bifurcation ends (10401); the outer edge profile of each bifurcation (10401) coincides with the outer tube (101) or the inner tube (102) with which it is in contact and forms a diverging channel in the annular gap (103) parallel to the axis of the annular gap (103).

3. A self-supporting bayonet tube according to claim 2, characterized in that the support (104) is provided with the tree-like bifurcation (1040) at both or either end in the direction of its own extension.

4. A self-supporting bayonet according to any one of claims 1 to 3, characterized in that said support (104) is provided with a plurality of spaced-apart around the circumference of the annular gap (103);

And/or the support (104) is provided with a plurality of spaced apart along the axial direction of the annular gap (103).

5. A self-supporting bayonet according to any one of claims 1 to 3, wherein one of the outer tube (101) and the inner tube (102) is fixedly connected to the support (104) and the other is in contact with the support (104) but not fixed;

or the outer tube (101) and the inner tube (102) are fixedly connected with the supporting piece (104).

6. A self-supporting bayonet tube according to claim 5, characterized in that the outer tube (101) and/or the inner tube (102) are fixedly connected to the support (104) by means of any one of the following forms: integrated into one piece, welding and buckle formula connection.

7. A self-supporting bayonet tube according to claim 1, wherein one end of the outer tube (101) is a closed end (1010) and the other end is an open end; one end of the inner tube (102) extends into the outer tube (101) from the opening end of the outer tube (101) and is spaced from the closed end (1010) of the outer tube (101), so that the cavity of the inner tube (102) is communicated with the annular gap (103); the end of the cavity channel of the inner tube (102) far away from the closed end (1010) is a steam inlet (105), and the end of the annular gap (103) far away from the closed end (1010) is a condensation outlet (106).

8. A heat exchanger comprising a housing (20) and a bayonet (10) arranged in the housing (20) for providing heat to a working medium inside the housing (20), characterized in that the bayonet (10) is a self-supporting bayonet according to any one of claims 6 to 7.

9. Heat exchanger according to claim 8, wherein the bayonet tubes (10) are provided with a plurality of groups, and wherein the direction of extension of the plurality of groups of bayonet tubes (10) is parallel to the direction of extension of the housing (20).

10. The heat exchanger according to claim 9, further comprising a grille (301) for mounting within the housing (20) and for securing the outer tube (101) in the bayonet tube (10).