Technical Field
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The present invention generally relates to a flooded heat exchanger and a refrigerating unit including the same.
Background Art
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In flooded heat exchangers of the prior art, heat exchange tubes are provided therein. A first medium is adapted to flow inside the heat exchange tubes, and a second medium is adapted to be accommodated outside the heat exchange tubes. The heat exchange tubes need to be submerged below a liquid surface of the second medium so that the first medium inside the heat exchange tubes can exchange heat with the second medium through tube walls of the heat exchange tubes. However, when a flooded heat exchanger is used in oscillating environments, such as a marine environment, the oscillating environment causes the liquid surface of the second medium to fluctuate, making it difficult to ensure that the heat exchange tubes are completely submerged, thereby affecting the heat exchange efficiency of the heat exchanger. In some application scenarios, when a flooded heat exchanger is used in a marine refrigerating unit, pitching and swaying occurring during ship navigation cause non-uniform flow of the second medium in the flooded heat exchanger along the length and width directions of the flooded heat exchanger and oscillation in the height direction thereof. Such flow and oscillation cause uneven distribution of the second medium within the flooded heat exchanger, which in turn causes a portion of the heat exchange tubes to be exposed above the liquid surface of the second medium, thereby reducing the heat exchange efficiency.
Summary of the Invention
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In a first aspect, the present application provides a flooded heat exchanger, comprising: a housing, which has a first medium inlet, a first medium outlet, a second medium inlet, and a second medium outlet, the housing defining a first accommodating cavity and a second accommodating cavity, and the first accommodating cavity and the second accommodating cavity being in fluid communication with the second medium inlet and the second medium outlet, wherein the first accommodating cavity is used for accommodating a second medium, the first accommodating cavity is arranged to be located below a liquid surface of the second medium, and the second accommodating cavity is arranged to be located above the liquid surface of the second medium; a plurality of heat exchange tubes, the heat exchange tubes being arranged in the housing in the length direction of the housing, and the heat exchange tubes being arranged in the first accommodating cavity, wherein two ends of each heat exchange tube are respectively in fluid communication with the first medium inlet and the first medium outlet, so that the heat exchange tube is used for accommodating a first medium; and a plurality of flow guide units arranged in the housing and arranged in the length direction of the housing; wherein each flow guide unit comprises: a wave blocking structure, the wave blocking structure comprising at least one enclosure plate, the heat exchange tubes passing through at least some of the at least one enclosure plate, and the at least one enclosure plate being configured to limit the second medium accommodated in the first accommodating cavity between the housing and the enclosure plates of each flow guide unit to at least partially limit the flow of the second medium in the length and width directions of the flooded heat exchanger.
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According to one aspect of the aforementioned flooded heat exchanger, each flow guide unit further comprises: a wave suppressing structure, the wave suppressing structure being arranged on a top side of at least some of the at least one enclosure plate, and the wave suppressing structure being configured to at least partially limit the flow of the second medium in the height direction of the flooded heat exchanger.
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According to one aspect of the aforementioned flooded heat exchanger, the at least one enclosure plate comprises a top plate, a pair of wing plates, and a pair of side plates, the pair of side plates being connected to two opposite sides of the top plate, and the pair of wing plates being connected between an outer side of the side plates and a side wall of the housing, such that a defined region for accommodating the second medium can be formed between the enclosure plates of adjacent wave blocking structures or between the housing and the enclosure plates of the wave blocking structure; the top plate and the wing plates are provided with a plurality of holes for the heat exchange tubes to pass through.
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According to one aspect of the aforementioned flooded heat exchanger, the plurality of flow guide units are arranged in a plurality of layers along a height of the housing, wherein the flow guide units in the odd-numbered layers and the flow guide units in the even-numbered layers are arranged in a staggered manner.
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According to one aspect of the aforementioned flooded heat exchanger, the wave blocking structure of each flow guide unit comprises a front-side connection portion and a rear-side connection portion, the front-side connection portion being located on the side plate proximate to a junction of the side plate and the top plate, and the rear-side connection portion being located on the side plate proximate to a junction of the side plate and the wing plate; wherein the front-side connection portion of each flow guide unit is configured to be coupled to the rear-side connection portion of an adjacent flow guide unit in an adjacent layer or to be suspended, and the rear-side connection portion of each flow guide unit is configured to be coupled to the front-side connection portion of an adjacent flow guide unit in the adjacent layer or to be suspended, thereby forming a layered structure arranged in the staggered manner through repetition of this configuration.
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According to one aspect of the aforementioned flooded heat exchanger, the wave suppressing structure is integrally formed with the wave blocking structure or is welded to the wave blocking structure.
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According to one aspect of the aforementioned flooded heat exchanger, the wave suppressing structure comprises pressing plates, a lower surface of the pressing plate being connected to a top of the enclosure plate and extending to both inner and outer sides of the corresponding enclosure plate, so as to block the flow of the second medium within the defined region in the height direction.
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According to one aspect of the aforementioned flooded heat exchanger, the wave suppressing structure comprises pressing plates, side surfaces of the pressing plates being connected to both sides of the top of the enclosure plate and extending from one side to the other side of the corresponding enclosure plate, so as to block the flow of the second medium within the defined region in the height direction.
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According to one aspect of the aforementioned flooded heat exchanger, the pressing plate is of a planar structure, an arc-shaped structure, a wave-shaped structure, or a polyline-shaped structure.
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According to one aspect of the aforementioned flooded heat exchanger, the flow guide units of a lowermost layer among the plurality of layers are provided with flow grooves at the bottom for the second medium to flow through.
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In a second aspect, the present application further provides a refrigerating unit, comprising: the flooded heat exchanger according to any one of the items in the first aspect.
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According to the aforementioned refrigerating unit, the refrigerating unit comprises an evaporator, an absorber, a condenser, a heat exchanger, a solution circulation pump, and a generator; wherein the generator comprises the flooded heat exchanger.
Brief Description of the Drawings
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- Figure 1 is a system diagram of a refrigerating unit comprising a flooded heat exchanger according to the present invention.
- Figure 2A is a stereoscopic structure diagram of the flooded heat exchanger in Figure 1 as observed from one perspective.
- Figure 2B is a stereoscopic structure diagram of the flooded heat exchanger in Figure 1 as observed from another perspective.
- Figure 3A is a top view of the flooded heat exchanger shown in Figure 2A.
- Figure 3B is a cross-sectional view of the flooded heat exchanger shown in Figure 2A taken along the section line A-A in Figure 3A.
- Figure 3C is a cross-sectional view of the flooded heat exchanger shown in Figure 2A taken along the section line B-B in Figure 3A.
- Figure 3D is a cross-sectional view of the flooded heat exchanger shown in Figure 2A taken along the section line C-C in Figure 3A.
- Figure 4 is a stereoscopic structure diagram of flow guide units and heat exchange tubes in the flooded heat exchanger shown in Figure 2A.
- Figure 5A is a stereoscopic structure diagram of a plurality of flow guide units in Figure 4.
- Figure 5B is a side view of the plurality of flow guide units in Figure 4.
- Figure 6 is a stereoscopic structure diagram of one embodiment of a single flow guide unit in Figure 5A.
- Figure 7 is a stereoscopic structure diagram of another embodiment of a single flow guide unit in Figure 5A.
- Figure 8 is a stereoscopic structure diagram of yet another embodiment of a single flow guide unit in Figure 5A.
Detailed Description of Embodiments
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Various specific implementations of the present invention will be described below with reference to the accompanying drawings, which constitute a part of the Specification. It should be understood that although terms, such as "front," "rear," "upper," "lower," "left," "right," "top," "bottom," etc., that represent directions are used in the present invention to describe various example structural parts and components of the present invention, these terms used herein are determined based on example orientations shown in the accompanying drawings for ease of illustration only. Since the embodiments of the present invention may be arranged in different orientations, these terms that represent directions are for illustration only and should not be regarded as limiting.
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Figure 1 is a system diagram of a refrigerating unit 100 comprising a flooded heat exchanger 210 of the present invention. As shown in Figure 1, the refrigerating unit 100 comprises an evaporator 102, an absorber 103, a condenser 104, and a generator 101. In the refrigerating unit 100 of the present application, water is used as a refrigerant and lithium bromide is used as an absorbent, and external refrigeration is achieved by utilizing changes in concentration of an aqueous lithium bromide solution and phase changes of water. Specifically, a concentrated lithium bromide solution, after absorbing refrigerant water vapor in the absorber 103, yields a dilute lithium bromide solution and releases heat to cooling water from a cooling water inlet 1042. The dilute lithium bromide solution then enters a heat exchanger 105 via a solution circulation pump 106, absorbs heat in the heat exchanger 105, and subsequently enters the generator 101. In the generator 101, the dilute lithium bromide solution absorbs heat from a first medium entering via a first medium inlet 1011, causing water in the dilute lithium bromide solution to evaporate, thereby obtaining a concentrated lithium bromide solution. The concentrated lithium bromide solution is then discharged from the generator 101 to the heat exchanger 105, releases heat in the heat exchanger 105, and returns to the absorber 103, thus completing a circulation of the lithium bromide solution.
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In the generator 101, the dilute lithium bromide solution is heated by driving heat source water and evaporates to obtain water vapor; the water vapor obtained by evaporation first enters the condenser 104, where it releases heat to a refrigerant from the absorber 103 and condenses into liquid water. Since an internal pressure of the condenser 104 is higher than an internal pressure of the evaporator 102, the liquid water discharged from the condenser 104 enters a bottom of the evaporator 102 after flashing, is then delivered to a top of the evaporator 102 by a refrigerant pump 107, and after being distributed by a drip box 1021, absorbs heat from chilled water from a chilled water inlet 1043. The liquid refrigerant water evaporates into refrigerant water vapor and then enters the absorber 103, where the refrigerant water vapor is absorbed by the concentrated lithium bromide solution distributed by a spray box 1031 of the absorber 103 to yield the dilute lithium bromide solution. The dilute lithium bromide solution enters the generator 101 as described above and evaporates to obtain water vapor. Thus, circulation of the refrigerant water is completed.
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The chilled water inlet 1043 is in fluid communication with a chilled water outlet 1044, allowing chilled water to flow through heat exchange tubes inside the evaporator 102, thereby providing heat to the refrigerant water in the evaporator 102 and thus providing cooling to the outside, i.e., performing external refrigeration.
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The first medium inlet 1011 and the first medium outlet 1012 are used to be in fluid communication with a first medium. When the flooded heat exchanger serves as the generator, the first medium typically has a relatively high temperature, and the first medium can enter heat exchange tubes inside the generator 101 to provide heat to the lithium bromide solution in the generator 101. In some other examples, the first medium may also be hot water, water vapor, flue gas, or the like.
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The cooling water inlet 1042 and a cooling water outlet 1041 are used to be in fluid communication with cooling water. The cooling water typically has a relatively low temperature to provide cooling to the lithium bromide solution in the absorber 103 and to the refrigerant water in the condenser 104. The cooling water enters heat exchange tubes inside the absorber 103 from the cooling water inlet 1042 first, absorbs the heat released by the concentrated lithium bromide solution when absorbing the refrigerant water vapor through the heat exchange tubes and get heated, then enters heat exchange tubes inside the condenser 104 to condense the refrigerant water vapor in the condenser 104, and finally is discharged from the condenser 104 via the cooling water outlet 1041.
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In the present embodiment, the generator 101 comprises the flooded heat exchanger 210. The flooded heat exchanger 210 comprises two working media, wherein a first medium of the flooded heat exchanger 210 is the driving heat source water, and a second medium is the lithium bromide solution. Heat exchange tubes are provided in the flooded heat exchanger 210, the heat exchange tubes being in fluid communication with the first medium inlet 1011 and the first medium outlet 1012 of the flooded heat exchanger 210, such that the driving heat source water flows through the inside of the heat exchange tubes. Furthermore, the heat exchange tubes are submerged in a dilute lithium bromide solution in the flooded heat exchanger 210. The dilute lithium bromide solution exchanges heat with the driving heat source water inside the heat exchange tubes through tube walls of the heat exchange tubes, causing the dilute lithium bromide solution to evaporate into a concentrated lithium bromide solution while generating refrigerant water vapor. The concentrated lithium bromide solution enters the heat exchanger 105 via the second medium outlet 1014.
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It should be noted that, although the flooded heat exchanger 210 is described herein as being used in a marine lithium bromide refrigerating unit, it should be understood that the flooded heat exchanger 210 is not limited to marine applications but may also be used in refrigerating units for other application scenarios, and is particularly suitable for application scenarios where pitching or swaying may occur, such as refrigeration applications in high-altitude towers or aircraft. Additionally, the flooded heat exchanger 210 of the present application is not limited to lithium bromide refrigerating units and may also be used in other suitable units, as long as a flooded heat exchanger is employed.
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Figures 2A and 2B illustrate stereoscopic structure diagrams of the flooded heat exchanger 210 according to the present invention as observed from two different perspectives, for illustrating an external structure of the flooded heat exchanger 210, wherein Figure 2A shows a stereoscopic structure diagram of the flooded heat exchanger 210 looking from front to rear, and Figure 2B shows a stereoscopic structure diagram of the flooded heat exchanger 210 looking from rear to front. As shown in Figures 2A and 2B, the flooded heat exchanger 210 comprises a housing 201. The housing 201 has a first medium inlet 1011, a first medium outlet 1012, a second medium inlet 1013, a second medium outlet 1014, a steam outlet 251, and an optional second medium drainage device 252. An accommodating cavity 320 is defined inside the housing 201, and several heat exchange tubes 311 are arranged in the accommodating cavity 320 (see Figure 3B). The first medium inlet 1011 and the first medium outlet 1012 are in fluid communication with the heat exchange tubes 311 inside the housing 201 to allow the first medium to flow through each heat exchange tube 311. The first medium serves as a heat source to provide heat and may be a liquid or a gaseous fluid. The second medium inlet 1013 and the second medium outlet 1014 are in fluid communication with the accommodating cavity 320 inside the housing 201 to allow the second medium to enter/leave the accommodating cavity 320. In the present embodiment, the flooded heat exchanger 210 serves as a generator, and therefore the first medium is driving heat source water, and the second medium is a lithium bromide solution. Specifically, a dilute lithium bromide solution enters the accommodating cavity 320 from the second medium inlet 1013, exchanges heat with the first medium in each heat exchange tube 311 within the accommodating cavity 320, causing water in the dilute lithium bromide solution to evaporate into water vapor and the dilute lithium bromide solution to be converted into a concentrated lithium bromide solution. The steam outlet 251 is connected to the condenser 104 shown in Figure 1 to deliver the generated water vapor to the condenser 104.
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In the embodiment shown in Figures 2A and 2B, the housing 201 is substantially in a shape of a rectangular box. A pair of tube sheets 202, 203 are provided on opposite sides in a length direction of the housing, respectively. The pair of tube sheets 202, 203 are provided with tube holes 205, 206, respectively. Two ends of each heat exchange tube 311 pass through the tube holes 205, 206 on the pair of tube sheets 202, 203 and are supported by the tube sheets 202, 203, respectively, and the first medium can flow into the heat exchange tube from one end of the heat exchange tube 311 and flow out from the other end of the heat exchange tube 311, such that the one end of the heat exchange tube 311 constitutes the first medium inlet 1011, and the other end of the heat exchange tube 311 constitutes the first medium outlet 1012.
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As shown in Figures 2A and 2B, a box-shaped valve body 204 protruding outward is provided on one side surface in a width direction of the housing 201, and the box-shaped valve body 204 is located at a right end of the housing 201. A bottom of the box-shaped valve body 204 is provided with the second medium inlet 1013 and the second medium outlet 1014, which are in fluid communication with the accommodating cavity 320. The second medium can enter the accommodating cavity 320 from the second medium inlet 1013 and can flow out of the accommodating cavity 320 from the second medium outlet 1014. A specific internal structure of the housing 201 will be described in detail in conjunction with Figures 3A to 3D.
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As shown in Figure 2A, a top of a right side of the housing 201 protrudes upward to divide the housing 201 into a first housing part 281 and a second housing part 282 in its length direction, wherein the first housing part 281 is located to the left of the second housing part 282, and a height of the first housing part 281 is lower than a height of the second housing part 282. Several heat exchange tubes 311 are arranged in the housing 201 along the same length direction. Moreover, a height of the several heat exchange tubes 311 is confined within a height range of the first housing part 281. The steam outlet 251 is provided at a top of the second housing part 282 to discharge steam, for example, to discharge steam to the condenser 104. Given a certain number of the heat exchange tubes 311, the height of the first housing part 281 and the height of the second housing part 282 are set according to an arrangement height of the heat exchange tubes 311. This not only reserves a space for steam flow outside the heat exchange tubes 311 within the second housing part 282 but also allows the second medium for submerging the heat exchange tubes 311 to be provided within the height range of the first housing part 281. Compared to a square housing with a height identical to that of the first housing part 281, the housing 201 of the present embodiment facilitates steam generation and discharge. Compared to a square housing with a height identical to that of the second housing part 282, the housing 201 of the present embodiment saves the amount of the second medium required to submerge the heat exchange tubes 311 and facilitates the submergence of the heat exchange tubes 311 by the second medium. Those skilled in the art can understand that the steam outlet 251 can be connected to the condenser 104 via a pipeline to discharge refrigerant water vapor generated by the flooded heat exchanger 210 from the steam outlet 251 to the condenser 104.
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In the present embodiment, the optional second medium drainage device 252 is arranged at a bottom of the housing 201. The second medium drainage device 252 is a valve that can be opened or closed. During operation of the generator, the second medium drainage device 252 is generally in a closed state. If the second medium in the accommodating cavity 320 needs to be drained after the generator stops working, the second medium in the accommodating cavity 320 can be discharged by opening the second medium drainage device 252.
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It should be noted that, although Figures 2A and 2B illustrate specific configurations and positions of the first medium inlet 1011, the first medium outlet 1012, the second medium inlet 1013, the second medium outlet 1014, the steam outlet 251, and the optional second medium drainage device 252, these configurations and positions are by no means limiting; and in other embodiments, their configurations and positions may be varied accordingly.
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Figures 3A to 3D illustrate an internal structure of the flooded heat exchanger, wherein Figure 3A is a top view of the flooded heat exchanger, Figure 3B is a cross-sectional view of the flooded heat exchanger shown in Figure 2A taken along the section line A-A in Figure 3A, Figure 3C is a cross-sectional view of the flooded heat exchanger shown in Figure 2A taken along the section line B-B in Figure 3A, and Figure 3D is a cross-sectional view of the flooded heat exchanger shown in Figure 2A taken along the section line C-C in Figure 3A. Figures 3B and 3C are used to more clearly illustrate the connection relationship among the second medium inlet 1013, the second medium outlet 1014, and a second medium internal tubing 353. As shown in Figures 3B and 3C, the second medium inlet 1013 is in fluid communication with the second medium internal tubing 353 through a tube joint 352, and the second medium internal tubing 353 is in fluid communication with the accommodating cavity 320, such that the second medium inlet 1013 is in fluid communication with the accommodating cavity 320. Specifically, an interior of the box-shaped valve body 204 has a hollow structure, which is in fluid communication with the accommodating cavity 320 in the housing 201. The box-shaped valve body 204 is provided with the tube joint 352 therein, and the tube joint 352 is generally in a hollow right-angled elbow shape. In the direction shown in Figure 3C, a bottom end of the tube joint 352 in a vertical direction is connected to the second medium inlet 1013, and a right end of the tube joint 352 in a horizontal direction is connected to the second medium internal tubing 353. The second medium outlet 1014 is directly connected to a bottom end of the box-shaped valve body 204 and is in fluid communication with the interior of the box-shaped valve body 204.
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The second medium internal tubing 353 is in a hollow elongated tube shape, which is arranged in the accommodating cavity 320 of the housing 201, with one end being connected to the tube joint 352 and the other end being open toward the accommodating cavity 320. For example, in the embodiment of Figure 3B, a left end of the second medium internal tubing 353 is connected to the tube joint 352, and a right end of the second medium internal tubing is open toward the accommodating cavity 320, enabling the second medium internal tubing 353 to be in fluid communication with the accommodating cavity 320. Certainly, the configuration of the second medium internal tubing 353 is not restricted to this. In the direction shown in Figure 3B, the second medium internal tubing 353 extends substantially horizontally from left to right from the tube joint 352 at the left end to a right end of the housing 201. Thus, the second medium can enter the tube joint 352 from the second medium inlet 1013, then be discharged into the accommodating cavity 320 along the second medium internal tubing 353, accumulate to a certain height to submerge several heat exchange tubes 311, and exchange heat with the first medium inside the heat exchange tubes 311. After the heat exchange is completed, the second medium exits the accommodating cavity 320 via the second medium outlet 1014.
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Those skilled in the art can understand that, although the present embodiment includes one tube joint 352 and one second medium internal tubing 353 that are connected to the second medium inlet 1013, in other embodiments, the tube joint 352 may be provided in a plurality or may have a plurality of outlets, and correspondingly, the second medium internal tubing 353 may also be provided in a plurality.
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Figures 3C and 3D illustrate a more specific internal structure of the flooded heat exchanger 210. As shown in Figures 3C and 3D, the housing 201 defines the accommodating cavity 320, and the accommodating cavity 320 comprises a first accommodating cavity 325 located at a lower position and a second accommodating cavity 326 located at an upper position. In an embodiment of the present application, the first accommodating cavity 325 and the second accommodating cavity 326 do not have a fixed interface but are defined by a liquid surface 327 formed by the second medium, and the first accommodating cavity 325 is located below the liquid surface 327 of the second medium and is used for accommodating the second medium. The second accommodating cavity 326 is located above the liquid surface 327 of the second medium and is used for accommodating water vapor.
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With further reference to Figures 3B to 3D, the heat exchange tubes 311 are arranged in the first accommodating cavity 325 and pass through a plurality of flow guide units 342, and the plurality of flow guide units 342 are arranged spaced apart from one another along the length direction of the housing 201 and are connected to an inner wall of the housing 201. Thus, the plurality of flow guide units 342 can support the heat exchange tubes 311 in the length direction and limit the flow of the second medium in the first accommodating cavity 325. Those skilled in the art can understand that, in the present embodiment, the plurality of flow guide units 342 are each independently connected to the inner wall of the housing 201; and in other embodiments, the plurality of flow guide units may also be configured as an integral piece to be connected as a whole to the inner wall of the housing 201.
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In the present embodiment, each flow guide unit comprises a wave blocking structure and a wave suppressing structure, and the wave blocking structure is used for at least partially limiting the flow of the second medium in the first accommodating cavity 325 in a length direction and a width direction of the flooded heat exchanger 210. The wave suppressing structure is used for at least partially limiting the flow of the second medium in the first accommodating cavity 325 in a height direction of the flooded heat exchanger 210. Thus, even in oscillating environments such as ships, the flooded heat exchanger 210 can retain the second medium in the first accommodating cavity 325 within a defined region enclosed by the housing 201, the wave blocking structure, and the wave suppressing structure, thereby ensuring that each heat exchange tube 311 remains submerged in the second medium and avoiding uneven distribution of the second medium. Those skilled in the art can understand that, in some embodiments, if oscillation in the environment is not significant, or if the height of the housing is limited, the flow guide units may include only the wave blocking structure without the wave suppressing structure, and the flow guide units may also not be completely submerged in the second medium.
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Specifically, the wave blocking structure comprises at least one enclosure plate 328, and the heat exchange tubes 311 pass through at least some of the at least one enclosure plate 328. In the present embodiment, the wave blocking structure comprises several enclosure plates 328, and each enclosure plate 328 comprises a portion extending along the length direction of the housing 201 and a portion extending along the width direction of the housing 201. The heat exchange tubes 311 pass through the portions of the several enclosure plates 328 that extend along the width direction of the housing 201. Furthermore, outermost edges of the several enclosure plates 328 in the width direction of the housing 201 are connected to inner sides of a pair of side walls 322 of the housing 201, such that each flow guide unit 342 is fixedly connected to the housing 201. In the present embodiment, the outermost edges of the several enclosure plates 328 in the width direction of the housing 201 are connected to the inner sides of the pair of side walls 322 of the housing 201 by welding. In other embodiments, the flow guide units may also be connected to the housing 201 by other means; and the flow guide units may also be connected to other parts of the housing 201, for example, the enclosure plates 328 of the flow guide units being connected to a bottom wall 323 of the housing 201. Thus, in the length direction of the housing 201, the second medium accommodated in the first accommodating cavity 325 can be limited between a front wall of the housing 201 and the enclosure plates 328 of each flow guide unit 342, between a rear wall of the housing 201 and the enclosure plates 328 of each flow guide unit 342, or between the enclosure plates 328 of adjacent flow guide units 342. In the width direction of the housing 201, the second medium accommodated in the first accommodating cavity 325 can be limited between the pair of side walls 322 of the housing 201. Even when the unit is applied in an oscillating environment, causing the flooded heat exchanger 210 to sway in the length direction or the width direction, the second medium accommodated in the first accommodating cavity 325 can still be retained between the housing 201 and the enclosure plates 328 of each flow guide unit 342 so as to at least partially limit the flow of the second medium in the length direction and the width direction of the flooded heat exchanger 210.
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Further, as shown in Figures 3C and 3D, the enclosure plates 328 of the bottommost flow guide units are recessed upward relative to the bottom wall 323 of the housing 201 to form flow grooves 324 for the second medium to flow through. The flow grooves 324 can allow the second medium to flow smoothly, at least at the bottom of the first accommodating cavity 325. That is to say, although the second medium accommodated in the first accommodating cavity 325 is retained within defined regions between the housing 201 and the enclosure plates 328 of each flow guide unit 342, the defined regions are in fluid communication with each other. This will facilitate the formation of the liquid surface 327 when the second medium flows into the first accommodating cavity 325 or the rapid discharge of the second medium from the first accommodating cavity 325.
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Figure 4 shows a stereoscopic structure diagram of the plurality of flow guide units 342 and the heat exchange tubes 311. As shown in Figure 4, the plurality of flow guide units 342 are arranged in layers. In the present embodiment, the plurality of flow guide units 342 are arranged in three layers; and in other embodiments, the plurality of flow guide units 342 may also be arranged in one layer, two layers, or more layers. Each flow guide unit 342 in the lowermost layer is provided with flow grooves 324 at the bottom. Arranging the flow guide units 342 in layers helps to retain the second medium within smaller regions. The flow guide units 342 in each layer are arranged side by side substantially parallel to each other in the length direction, and the flow guide units 342 in adjacent layers are arranged in a staggered manner. Each heat exchange tube 311 sequentially passes through the flow guide units 342 in one layer, such that a section of each heat exchange tube 311 in the length direction is located within a defined region of the flow guide unit 342 that is between the housing 201 and the enclosure plate 328 of the flow guide unit 342, and in some cases, between the several enclosure plates 328.
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Figures 5A and 5B illustrate the positional relationship of the plurality of flow guide units 342. Figure 5A shows a stereoscopic structure of the layered arrangement of the plurality of flow guide units 342, and Figure 5B shows a side view of the plurality of flow guide units 342 shown in Figure 5A. As shown in Figures 5A and 5B, the plurality of flow guide units 342 are arranged in three layers along a height of the housing 201, wherein the flow guide units 342 in the odd-numbered layers and the flow guide units 342 in the even-numbered layers are arranged in a staggered manner. Specifically, each flow guide unit 342 comprises, in the length direction, a front-side connection portion 463 and a rear-side connection portion 464. In the present embodiment, each flow guide unit 342 is substantially of a ""-shaped structure, and a middle portion of the flow guide unit 342 in a width direction protrudes forward relative to both sides thereof. The front-side connection portion 463 is located at a front side of the middle portion of the flow guide unit 342 in the width direction, and the rear-side connection portion 464 is located at a rear side of the middle portion of the flow guide unit 342 in the width direction. The front-side connection portion 463 is formed at a corner portion on the front side, and the rear-side connection portion 464 is formed at a corner portion on the rear side. In the length direction, the flow guide units 342 of two adjacent layers are not completely staggered but partially overlap to facilitate connection between the flow guide units 342. More specifically, the front-side connection portion 463 of each flow guide unit 342 overlaps with the rear-side connection portion 464 of an adjacent flow guide unit 342 in an adjacent layer to be coupled or to be arranged in a suspended manner, and the rear-side connection portion 464 of each flow guide unit 342 overlaps with the front-side connection portion 463 of the adjacent flow guide unit 342 in the adjacent layer to be coupled or to be arranged in a suspended manner, thereby forming the layered structure arranged in a staggered manner through repetition of this configuration. In the present embodiment, the coupling of the front-side connection portion 463 and the rear-side connection portion 464 is achieved by welding. Coupling by welding at the front-side connection portion 463 and the rear-side connection portion 464 at the corner portions can make the coupling between the flow guide units 342 more secure even when the welding area on each flow guide unit 342 is limited. The suspended arrangement is attributable to the aforementioned staggered arrangement, as the front-side connection portion 463 or the rear-side connection portion 464 of the foremost or rearmost flow guide unit 342 is suspended. For example, in the embodiment shown in Figures 5A and 5B, among the flow guide units 342 of the second layer, the front-side connection portion 463 of the foremost flow guide unit 342 is arranged in a suspended manner; and among the flow guide units 342 of the first and third layers, the rear-side connection portion 464 of the rearmost flow guide unit 342 is arranged in a suspended manner.
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Figure 6 is a stereoscopic structure diagram of an embodiment of a flow guide unit in Figure 5A for illustrating a specific structure of the flow guide unit 342. As shown in Figure 6, the several enclosure plates 328 of the flow guide unit 342 each comprises a top plate 3021, a pair of wing plates 3023, and a pair of side plates 646. The top plate 3021 is located on a foremost side of the flow guide unit 342 and extends in a width direction. The pair of side plates 646 are connected in parallel to opposite sides of the top plate 3021 and extend in the length direction. The pair of wing plates 3023 are connected side by side between an outer side of the corresponding side plate 646 and the side wall 322 of the housing 201 and extend in a direction parallel to the top plate 3021. That is to say, the pair of side plates 646 are formed by extending rearward from edges on both sides of the top plate 3021 along the length direction, and the pair of wing plates 3023 are formed by extending outward from edges on the rear sides of the corresponding side plates 646 along a width direction. Therefore, corners at junctions where the top plate 3021 and the pair of side plates 646 meet are substantially right-angled, and corners at junctions where the side plates 646 and the wing plates 3023 meet are substantially right-angled. Thus, the five enclosure plates 328 of the flow guide unit 342 substantially form a ""-shaped structure.
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In the present embodiment, an outer edge of each wing plate 3023 is connected to the side wall 322 of the housing 201 by a welding process. A plurality of holes 644 are provided on the top plate 3021 and the wing plates 3023 for the heat exchange tubes 311 to pass through. Certainly, the enclosure plates 328 are not limited to this structure. For example, the flow guide unit 342 may also be designed to include only a top plate and a pair of side plates, with the pair of side plates extending obliquely from the top plate to be connected to the side walls of the housing, holes being provided on the top plate and the side plates for the heat exchange tubes to pass through, and the pair of side plates being connected to the side walls of the housing, etc., depending on the circumstances. In the present embodiment, the front-side connection portion 463 is located on a top edge and a bottom edge of the side plate 646 proximate to a junction where the side plate 646 and the top plate 3021 meet, and the rear-side connection portion 464 is located on a top edge and a bottom edge of the side plate 646 proximate to a junction where the side plate 646 and the wing plate 3023 meet. Those skilled in the art can understand that, "proximate to" herein means that the front-side connection portion 463 and the rear-side connection portion 464 are located on a side of the corresponding connection portion of the side plate 646 and have a certain length so as to provide a certain overlapping range when coupling to an adjacent connection portion. Therefore, the structure of the enclosure plates 328 of the flow guide units 342 of the present application facilitates the welding process.
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Still as shown in Figure 6, each flow guide unit 342 further comprises a wave suppressing structure. The wave suppressing structure is arranged on a top side of at least one enclosure plate 328 of each flow guide unit 342 and extends outward in a flared manner from a top edge of the corresponding enclosure plate 328 at an angle inclined relative to the height direction so as to block flow of the second medium, which is confined within the defined region, in the height direction, thereby at least partially limiting the flow of the second medium in the height direction of the flooded heat exchanger 210. In some embodiments, the wave suppressing structure and the wave blocking structure may be integrally formed, or the wave suppressing structure and the wave blocking structure may be fixedly connected together by means such as welding.
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Specifically, the wave suppressing structure comprises several pressing plates 643. The several pressing plates 643 are arranged on tops of all enclosure plates 328 each comprising the top plate 3021, the pair of side plates 646, and the pair of wing plates 3023. However, in other embodiments, the several pressing plates 643 may also be arranged only on a top of one or more of the plurality of enclosure plates 328 as needed. In the embodiment shown in Figure 6, each pressing plate 643 is a planar structure extending in a horizontal direction, that is to say, each pressing plate 643 is perpendicular to the height direction. A lower surface of the pressing plate 643 is connected to a middle position of a top surface of the corresponding enclosure plate 328 so as to leave space for the corner portions at the junctions of the top plate 3021, the pair of side plates 646, and the pair of wing plates 3023, for example, to leave space for the front-side connection portion 463 and the rear-side connection portion 464 on the pair of side plates 646. Furthermore, the pressing plate 643 extends horizontally to both inner and outer sides of the corresponding enclosure plate 328 by a certain width. This width is configured to be capable of blocking the flow of the second medium within the defined region in the height direction, without affecting the flow of steam.
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In the present embodiment, each flow guide unit 342 comprises a wave suppressing structure. The flow guide units 342 arranged in multiple layers, compared to flow guide units 342 arranged in a single layer, can provide a better wave suppressing effect, resulting in a lower splash height of the second medium and a reduced amount of splashed second medium. Even when the unit is applied in an oscillating environment, causing the flooded heat exchanger 210 to sway in the height direction, the second medium within the defined region can still be retained between the housing 201 and the enclosure plates 328 of each flow guide unit 342 so as to limit the flow of the second medium in the height direction.
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Figure 7 shows a stereoscopic structure diagram of a second embodiment of a flow guide unit. As shown in Figure 7, the structure of a flow guide unit 742 is substantially the same as the structure of the flow guide unit 342 in Figure 6, with the difference lying in the structure of a wave suppressing structure of the flow guide unit 742 being different from the structure of the wave suppressing structure of the flow guide unit 342. Specifically, in the present embodiment, the wave suppressing structure comprises several pressing plates 743. The several pressing plates 743 are arranged on the tops of all the enclosure plates 328. Similarly, in other embodiments, the several pressing plates 743 may also, depending on circumstances, be arranged only at middle positions on the tops of one or more of the plurality of enclosure plates 328 so as to leave space for corner portions at junctions of the enclosure plates 328. In the embodiment shown in Figure 7, each pressing plate 743 is of a polyline-shaped structure. In the present embodiment, the pressing plate 743 no longer extends in the horizontal direction but instead extends slightly inclined relative to a horizontal plane to form the polyline shape. Furthermore, the pressing plate 743 is no longer connected to a top surface of each enclosure plate 328 but is instead formed by extension from a side surface at the top of each enclosure plate 328 to an opposite side. Thus, the pressing plate 743 can also block the flow of the second medium within the defined region in the height direction.
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Figure 8 shows a stereoscopic structure diagram of a third embodiment of a flow guide unit. As shown in Figure 8, the structure of a flow guide unit 842 is substantially the same as the structure of the flow guide unit 742, with the difference lying in the shape of a pressing plate 843 in the flow guide unit 842 being different from the shape of the pressing plate 743 in the flow guide unit 742. Specifically, in the present embodiment, each pressing plate 843 is of an arc-shaped structure with a raised middle portion so as to block the flow of the second medium within the defined region in the height direction.
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Those skilled in the art can understand that the shape of the pressing plate is not limited to the several embodiments described above, so long as the pressing plate can be conveniently connected to a top of the enclosure plate 328 and extend in a flared manner substantially from the top of the enclosure plate 328 to both inner and outer sides of the enclosure plate, and for example, the pressing plate may also be of a wave-shaped structure.
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In summary, because the flooded heat exchanger of the present application is provided with a wave blocking structure therein, the second medium in the flooded heat exchanger can be confined within relatively small defined regions enclosed by the flow guide units and the housing, thereby limiting the flow of the second medium in the length direction and the width direction of the flooded heat exchanger. Furthermore, because the flooded heat exchanger of the present application is further provided with a wave suppressing structure therein, the second medium in the flooded heat exchanger can be confined within a certain height range, thereby limiting the flow of the second medium in the height direction of the flooded heat exchanger.
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Therefore, in a unit employing the flooded heat exchanger of the present application, even when the unit is used in oscillating environments such as marine applications, the second medium can still submerge each heat exchange tube. Consequently, uneven distribution of the second medium within the flooded heat exchanger and exposure of a portion of the heat exchange tubes above the liquid surface of the second medium can be avoided, thereby improving heat exchange efficiency.
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Although the present invention has been disclosed in conjunction with the embodiments described above, various alternatives, modifications, variations, improvements and/or substantial equivalents, whether currently known or foreseeable now or in the future, are apparent to those skilled in the art. In addition, the technical effects and/or technical problems described in the present specification are exemplary and not limiting. Therefore, the disclosure in the present specification may be used to solve other technical problems and have other technical effects. Accordingly, the embodiments of the present invention, as set forth above, are intended to be illustrative and not limiting. Various changes can be made without departing from the spirit or scope of the present invention. Accordingly, the present invention is intended to cover all known or earlier developed alternatives, modifications, variations, improvements and/or substantial equivalents.