CN113686177A - Linear temperature-equalizing flow-guiding shell-and-tube heat exchanger - Google Patents
Linear temperature-equalizing flow-guiding shell-and-tube heat exchanger Download PDFInfo
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- CN113686177A CN113686177A CN202011210293.8A CN202011210293A CN113686177A CN 113686177 A CN113686177 A CN 113686177A CN 202011210293 A CN202011210293 A CN 202011210293A CN 113686177 A CN113686177 A CN 113686177A
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- wall
- gas
- heat exchanger
- tube
- outlet
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
- F28D7/16—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged in parallel spaced relation
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F13/00—Arrangements for modifying heat-transfer, e.g. increasing, decreasing
- F28F13/06—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by affecting the pattern of flow of the heat-exchange media
- F28F13/12—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by affecting the pattern of flow of the heat-exchange media by creating turbulence, e.g. by stirring, by increasing the force of circulation
- F28F13/125—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by affecting the pattern of flow of the heat-exchange media by creating turbulence, e.g. by stirring, by increasing the force of circulation by stirring
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F2250/00—Arrangements for modifying the flow of the heat exchange media, e.g. flow guiding means; Particular flow patterns
- F28F2250/10—Particular pattern of flow of the heat exchange media
- F28F2250/102—Particular pattern of flow of the heat exchange media with change of flow direction
Abstract
The invention provides a uniform-temperature shell-and-tube heat exchanger, wherein a flow guide plate extending from the inner wall of an outlet pipe to the center of the outlet pipe is arranged in the outlet pipe, the flow guide plate comprises a first straight line wall and a second straight line wall extending from the inner wall, an acute angle formed by the tangent line at the joint of the first straight line wall and the inner wall is smaller than an acute angle formed by the tangent line at the joint of the second straight line wall and the inner wall, the first straight line wall and the second straight line wall are bent towards the gas flowing direction, and the intersection point of the first wall and the second wall is positioned at the downstream of the joint of the first straight line wall and the inner wall and is positioned at the downstream of the joint of the second straight line wall and the inner wall. The invention provides a novel shell-and-tube heat exchanger, wherein a flow guide plate is arranged in a gas outlet pipe, so that a part of gas flows along the flow guide plate and is guided to the opposite direction, and the gas is fully mixed with the gas entering in the opposite direction, thereby realizing uniform temperature of the gas, realizing the requirement of further heat exchange and prolonging the service life of a product.
Description
Technical Field
The invention relates to a heat exchanger, in particular to a shell-and-tube heat exchanger with gas participating in heat exchange.
Background
The shell-and-tube heat exchanger is widely applied to industries such as chemical industry, petroleum industry, refrigeration industry, nuclear energy industry and power industry, and due to the worldwide energy crisis, the demand of the heat exchanger in industrial production is more and more, and the quality requirement of the heat exchanger is higher and more. In recent decades, although compact heat exchangers (plate type, plate fin type, pressure welded plate type, etc.), heat pipe type heat exchangers, direct contact type heat exchangers, etc. have been rapidly developed, because the shell and tube type heat exchangers have high reliability and wide adaptability, they still occupy the domination of yield and usage, and according to relevant statistics, the usage of the shell and tube type heat exchangers in the current industrial devices still accounts for about 70% of the usage of all heat exchangers.
The gas heater may take the form of a shell and tube heat exchanger. If the gas heat exchanger has serious problems of ash blockage, corrosion, air leakage and the like under the long-term operation condition, the tangential temperature difference of the outlet gas of the gas heat exchanger is larger. Meanwhile, the temperature of the outlet gas at different positions is not uniform due to the nonuniform heat exchange inside the heat exchanger. When the gas is distributed to different occasions for use, overheating or overcooling conditions can occur due to uneven gas temperature, and the operation is affected.
Therefore, to foretell defect, this patent has proposed a new shell and tube heat exchanger, aims at through setting up the distributor to shell and tube heat exchanger outlet pipe to reach outlet temperature even, in order to realize further heat transfer needs, improve product life.
Disclosure of Invention
The present invention provides a new heat exchange tube heat exchanger to solve the foregoing technical problems.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a uniform temperature shell-and-tube heat exchanger comprises an upper collecting tank, a lower collecting tank and a heat exchange tube arranged between the upper collecting tank and the lower collecting tank; the heat exchanger comprises a gas inlet and a gas outlet, gas flows in from the gas inlet, exchanges heat with fluid in the heat exchange tube in the heat exchanger and then flows out from the gas outlet, and the heat exchanger is characterized in that the gas outlet is connected with an outlet tube, a flow guide plate extending from the inner wall of the outlet tube to the center of the outlet tube is arranged in the outlet tube, the flow guide plate comprises a first straight wall and a second straight wall extending from the inner wall, wherein the acute angle formed by the first straight wall and the inner wall is smaller than the acute angle formed by the second straight wall and the inner wall, the first straight wall and the second straight wall extend towards the gas flowing direction, and the intersection point of the first wall and the second wall is positioned at the downstream of the connection position of the first straight wall and the inner wall and is positioned at the downstream of the connection position of the second straight wall and the inner wall.
Preferably, a plurality of rows of flow guide plates are arranged on the inner wall of the outlet pipe along the flowing direction of the gas, and the flow guide plates of adjacent rows are distributed in a staggered manner.
Preferably, the distance between the intersection point and the inner wall of the outlet pipe is 0.3 to 0.5 times the diameter of the outlet pipe.
Preferably, the length of the first rectilinear wall is greater than the length of the second rectilinear wall.
Preferably, the total radian of the circular arcs connecting the drainage plates of the same layer with the inner wall is 150-180 degrees.
Preferably, the length L2 of the first straight wall and the length L1 of the second straight wall, the acute angle between the first line and the inner wall is a2, the acute angle between the second line and the inner wall is a1, the distance S between the centers of the adjacent flow guide plates in the flowing direction of the gas, that is, the distance between the centers of the adjacent flow guide plates, the center being the midpoint of the connecting line of the connecting points of the first straight wall and the second straight wall and the inner wall, meets the following requirements:
n = a-b × ln (M), wherein N = (L1+ L2)/S, M = sin (a2)/sin (a 1); ln is a function of the logarithm of the number,
0.3125<a<0.3130，0.1268<b<0.1272。
compared with the prior art, the flat heat exchange tube has the following advantages:
1) the invention provides a novel shell-and-tube heat exchanger, wherein a linear drainage plate is arranged in a gas outlet pipe, so that a part of gas flows along the drainage plate and is guided to the opposite direction, and the gas is fully mixed with the gas entering in the opposite direction, thereby realizing uniform temperature of the gas, realizing the requirement of further heat exchange and prolonging the service life of a product.
2) According to the invention, through carrying out extensive research on the heat exchange rule caused by the change of each parameter of the drainage plate, the drainage plate structure of the heat exchanger is optimized under the condition of meeting the flow resistance, so that the optimal outlet gas temperature equalizing effect is achieved.
3) According to the invention, through reasonable layout, the drainage plates of adjacent rows are arranged in a staggered manner, so that gas is further fully mixed, and the temperature is uniform.
4) The invention further promotes the full mixing by setting the distribution change of parameters such as the size, the number angle and the like of the drainage plate along the flowing direction of the fluid.
5) According to the invention, the distance of the drainage plate is widely researched, a formula of the minimum distance is designed, the mixing requirement is fully met, the problems of uneven mixing and increased flow resistance are avoided, and the optimal outlet gas temperature equalizing effect is achieved.
Drawings
Fig. 1 is a schematic structural view of a heat exchanger according to the present invention.
FIG. 2 is an axial cut-away view of an outlet tube with a flow guide plate according to the present invention.
Figure 3 is a schematic diagram of the size of the outlet tube-containing baffle of the present invention.
FIG. 4 is a perspective view of 1 drainage plate per layer.
FIG. 5 is a perspective view of 3 drainage plates per layer.
FIG. 6 is a perspective view of 1 drainage plate per layer.
Fig. 7 is an exploded perspective view of one side of the outlet tube of fig. 6.
The reference numbers are as follows:
1 heat exchange tube, 2 flow guide plates, 21 first straight wall, 22 second straight wall, 23 intersection point, 3 inlet tube, 4 outlet tube, 5 outlet tube, 6 gas inlet, 7 gas outlet, 8 upper header and 9 lower header.
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings.
In this document, "/" denotes division and "×", "denotes multiplication, referring to formulas, if not specifically stated.
Fig. 1 discloses a shell and tube heat exchanger for making the outlet gas temperature uniform. As shown in fig. 1, the heat exchanger includes an upper header 8, a lower header 9, and a heat exchange tube 1 disposed between the upper and lower headers; the heat exchanger comprises a gas inlet 6 and a gas outlet 7, wherein gas flows in from the gas inlet 6, exchanges heat with fluid in the heat exchange tube 1 in the heat exchanger and then flows out from the gas outlet 7.
As a modification, the gas outlet 7 is connected with the outlet pipe 5, as shown in fig. 2, a flow guide plate 2 extending from the inner wall 51 of the outlet pipe to the center of the outlet pipe is arranged in the outlet pipe 5, the flow guide plate 2 comprises a first straight wall 21 and a second straight wall 22 extending from the inner wall, wherein the acute angle formed by the first straight wall 21 and the inner wall is smaller than the acute angle formed by the second straight wall 22 and the inner wall, the first straight wall 21 and the second straight wall 22 extend toward the gas flow direction, and the intersection 23 of the first straight wall 21 and the second straight wall 22 is located downstream of the connection of the first straight wall 21 and the inner wall 51 and downstream of the connection of the second straight wall 22 and the inner wall. The shape of the flow guide plate 2 is that of the first and second rectilinear walls 21, 22 and the inner wall rotated along the outlet tube axis.
The invention provides a gas heat exchanger, which is characterized in that the flow guide plate is arranged in the gas outlet pipe, so that a part of gas flows along the flow guide plate and is guided to the opposite direction, and the gas is fully mixed with the gas entering in the opposite direction, thereby realizing uniform temperature of the gas, realizing the requirement of further heat exchange and prolonging the service life of the product. And through setting up the second straight line wall, the slope of second straight line wall is little moreover for gas that the opposite direction water conservancy diversion was come from also can be along the upward direction motion of second straight line wall direction, increases the buffering, reduces flow resistance.
According to the invention, the drainage plate is respectively provided with the first linear wall and the second linear wall, the two linear walls are arranged, so that the gas disturbance effect is better, the area of the drainage plate contacting the inner wall is increased, and the stability is improved.
Preferably, the first rectilinear wall 21 at the location of the intersection point 23 forms an angle of 30-60 deg. with the axis of the outlet duct, preferably 45 deg.. By providing this angle, fluid can be quickly directed to the opposite downstream location, and flow resistance can be further reduced.
Preferably, as shown in fig. 2, a plurality of layers of flow guide plates 2 are arranged on the inner wall of the outlet pipe 5 along the flowing direction of the gas, and the flow guide plates of the adjacent layers are staggered. Through the staggered distribution of the drainage plates of adjacent rows, the gas can fully move to the opposite position in the outlet pipe, and the full and uniform mixing is ensured. For example, FIGS. 2, 4, and 6 show one drainage plate per layer, with the total arc of one plate being 150 and 180. Of course, multiple drainage plates can be arranged on each layer, for example, three drainage plates are arranged on each layer in the angle of 150 and 180 degrees in total in FIG. 5.
Preferably, the distance between the intersection point and the inner wall of the outlet pipe is 0.3 to 0.5 times, preferably 0.4 times the diameter of the outlet pipe. With this arrangement, the air has less flow resistance on thorough mixing.
Preferably, the length of the first rectilinear wall is greater than the length of the second rectilinear wall.
Preferably, the total radian of the circular arcs connecting the drainage plates of the same layer with the inner wall is 150-180 degrees. This parameter set ensures thorough mixing while meeting the resistance requirements. For example, FIG. 2 shows one drainage plate per layer, with a total arc of 150 and 180. Of course, each layer of the flow guide plate can be provided with a plurality of flow guide plates, for example, two flow guide plates are provided with a total arc of 150-.
As preferablely, A layer drainage plate sets up the polylith, sets up the interval between the A drainage plate, and the equidistant setting of A drainage plate, B layer are the adjacent row on A layer, follow the direction of flow and observe, and B layer drainage plate sets up the interval position department on A layer. Through the complementation of the positions of the drainage plates of the adjacent layers, the gas can fully move to the opposite position in the outlet pipe, and the full and uniform mixing is ensured. It should be noted that the layer a and the layer B are not specifically designated herein, and A, B is only used as a distinction and is used as an adjacent layer.
Preferably, a plurality of flow guide plates are arranged on the inner wall of the outlet pipe along the flowing direction of the gas, and the distribution density of the flow guide plates is smaller and smaller along the flowing direction of the gas. Because the mixing degree of the gas is better and better along with the continuous movement of the gas, the distribution density is required to be set to be smaller and smaller so as to reduce the flow resistance, and the temperature equalizing effect achieves the basically same effect on the aspects of reducing the resistance and saving the material cost.
Preferably, the distribution density of the flow guide plates is increased to a smaller and smaller extent along the flow direction of the gas. The effect is obtained through a large number of numerical simulation and experimental research results, and the research finds that the rule accords with the rule of gas motion, and the temperature equalizing effect achieves the basically same effect on the aspects of further reduction of resistance and saving of material cost.
Preferably, a plurality of flow guiding plates are arranged on the inner wall of the outlet pipe along the flowing direction of the gas, and the size of the flow guiding plates is smaller along the flowing direction of the gas. Because the mixing degree of the gas is better and better along with the continuous movement of the gas, the size is required to be smaller and smaller so as to reduce the flow resistance, and the temperature equalizing effect achieves the same effect in the aspects of reducing the resistance and saving the material cost.
Preferably, a plurality of flow guiding plates are arranged on the inner wall of the outlet pipe along the flowing direction of the gas, and the size of the flow guiding plates is gradually reduced along the flowing direction of the gas. The effect is obtained through a large number of numerical simulation and experimental research results, and the research finds that the rule accords with the rule of gas motion, and the temperature equalizing effect achieves the basically same effect on the aspects of further reduction of resistance and saving of material cost.
Through a large amount of numerical simulation and experimental study discovery, the angle and the size of drainage plate have very big influence to heat transfer and misce bene, drainage plate and inner wall contained angle are on the small side, can lead to mixing effect variation, and lead to the drainage plate size too big, influence the flow resistance, the contained angle is on the large side, it is not good to lead to stirring fluid effect, the resistance grow, mixing effect variation, the interval of drainage plate is too big, can lead to the vortex effect not good, the interval undersize can lead to increasing the movement resistance, consequently, this application has obtained nearest drainage plate structure size optimization relation through a large amount of data simulation and experiments.
Preferably, the length L2 of the first straight wall and the length L1 of the second straight wall, the acute angle between the first line and the inner wall is a2, the acute angle between the second line and the inner wall is a1, the distance S between the centers of the adjacent flow guide plates in the flowing direction of the gas, that is, the distance between the centers of the adjacent flow guide plates, the center being the midpoint of the connecting line of the connecting points of the first straight wall and the second straight wall and the inner wall, meets the following requirements:
n = a-b × ln (M), wherein N = (L1+ L2)/S, M = sin (a2)/sin (a 1); ln is a function of the logarithm of the number,
0.3125<a<0.3130，0.1268<b<0.1272；
preferably, 0.25< M <0.75,0.34< N <0.44,45< a1<75 °, 15< a2<65 °,350< S <500mm, 70< L2<130mm, 30< L1<90 mm.
The optimal design requirements of the drainage plate structure can be met by the various types. The structural optimization formula is a main improvement point of the invention, is the most optimized formula which is researched by a large number of numerical simulations and experiments, and is not common knowledge in the field.
Further preferably, a =0.3128 and b = 0.1270.
It is found in data simulation and experiment that the interval between the drainage plate must be greater than certain distance, otherwise can lead to the fluid to guide to opposite direction through last drainage plate, but if the interval undersize between the drainage plate, can lead to gaseous flowing opposite, not fully filled with whole pipeline yet, set up the drainage plate this moment, play not can not play the mixed effect, the drainage plate only plays a baffling board effect, does not guide the effect of mixing, can only increase the flow resistance. Therefore, the design scheme of the minimum spacing of the drainage plate is provided through a great deal of research, and the design of the drainage plate has certain guiding significance.
The vertical point of the intersection point 23 on the inner wall, the line formed by the intersection point and the vertical point is a third line, the distance between the connecting point of the first straight line wall and the inner wall and the vertical point is H, the inner pipe diameter of the outlet pipe is R, and the distance S is designed in the following mode:
S1>=a*H+b*((H)2+R2)(1/2)；
wherein 2.5<a<3.5,
，1.552<c<1.560，
Preferably, a =3.2, c = 1.557;
according to the invention, through a large number of experiments and numerical simulation, the minimum design distance of the drainage plate is obtained, the resistance is reduced through the design distance, and meanwhile, the full mixing can be realized.
Although the present invention has been described with reference to the preferred embodiments, it is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (6)
1. A uniform temperature shell-and-tube heat exchanger comprises an upper collecting tank, a lower collecting tank and a heat exchange tube arranged between the upper collecting tank and the lower collecting tank; the heat exchanger comprises a gas inlet and a gas outlet, gas flows in from the gas inlet, exchanges heat with fluid in the heat exchange tube in the heat exchanger and then flows out from the gas outlet, and the heat exchanger is characterized in that the gas outlet is connected with an outlet tube, a flow guide plate extending from the inner wall of the outlet tube to the center of the outlet tube is arranged in the outlet tube, the flow guide plate comprises a first straight wall and a second straight wall extending from the inner wall, wherein the acute angle formed by the first straight wall and the inner wall is smaller than the acute angle formed by the second straight wall and the inner wall, the first straight wall and the second straight wall extend towards the gas flowing direction, and the intersection point of the first wall and the second wall is positioned at the downstream of the connection position of the first straight wall and the inner wall and is positioned at the downstream of the connection position of the second straight wall and the inner wall.
2. The heat exchanger of claim 1, wherein the intersection point is spaced from the inner wall of the outlet tube by a distance of 0.3 to 0.5 times the diameter of the outlet tube.
3. The heat exchanger of claim 1, wherein the first linear wall has a length greater than a length of the second linear wall.
4. The heat exchanger of claim 1, wherein the total arc of the arc connecting the flow-directing plates of the same layer to the inner wall is 150 ° and 180 °.
5. The heat exchanger of claim 1, wherein the length of the first linear wall L2, the length of the second linear wall L1, the acute angle between the first line and the inner wall a2, and the acute angle between the second line and the inner wall a1, the distance S between the center points of the adjacent flow guide plates in the flow direction of the gas, which are the midpoints between the connection points of the first linear wall and the second linear wall with the inner wall, satisfies the following requirements:
n = a-b × ln (M), wherein N = (L1+ L2)/S, M = sin (a2)/sin (a 1); ln is a function of the logarithm of the number,
0.3125<a<0.3130，0.1268<b<0.1272。
6. a shell-and-tube heat exchanger, the said heat exchanger includes upper and lower header and heat exchange tube set up between upper and lower header; the heat exchanger comprises a gas inlet and a gas outlet, wherein gas flows in from the gas inlet, exchanges heat with fluid in the heat exchange tube in the heat exchanger, and then flows out from the gas outlet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011210293.8A CN113686177A (en) | 2020-11-03 | 2020-11-03 | Linear temperature-equalizing flow-guiding shell-and-tube heat exchanger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011210293.8A CN113686177A (en) | 2020-11-03 | 2020-11-03 | Linear temperature-equalizing flow-guiding shell-and-tube heat exchanger |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113686177A true CN113686177A (en) | 2021-11-23 |
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ID=78576178
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011210293.8A Withdrawn CN113686177A (en) | 2020-11-03 | 2020-11-03 | Linear temperature-equalizing flow-guiding shell-and-tube heat exchanger |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113686177A (en) |
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2020
- 2020-11-03 CN CN202011210293.8A patent/CN113686177A/en not_active Withdrawn
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Application publication date: 20211123 |
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