High-efficiency low-resistance cross-flow heat pipe heat exchanger

Abstract

The application provides a high-efficiency low-resistance cross-flow heat pipe heat exchanger, which adopts a twisted non-circular cross-section heat pipe in the heat insulation section of the heat pipe, so that the flow directions of the hot side fluid and the cold side fluid of the heat exchanger are the same as the long axis direction of the cross section of the heat pipe, the heat exchanger can be flexibly arranged by being turned in any direction, the pressure loss of the fluid in the heat exchange cavity is finally significantly reduced, the energy consumption of the fan is reduced, meanwhile, the heat exchange effect between the fluid in the heat exchange cavity and the heat pipe bundle is also significantly improved. In addition, the outer walls of the condensation section and the evaporation section are arranged with non-circular fins corresponding to the cross section of the heat pipe in the form of dense in the middle and sparse at both ends, the characteristics that the flow speed of the main flow area is large and the flow speed of the near wall area is small are fully utilized, the fin heat exchange efficiency is effectively improved, and the material use is saved.

Description

Technical Field

[0001] This invention relates to the field of heat exchange equipment, and in particular to a high-efficiency, low-resistance cross-flow heat pipe heat exchanger. Background Technology

[0002] In recent decades, with the increasing maturity of heat pipe heat exchanger technology, it has played an increasingly important role in energy-saving renovations in power plants, steel metallurgy, petrochemicals, waste heat recovery, and thermal management of electronic equipment. For example, in the application of flue gas waste heat recovery, gravity heat pipe heat exchangers are currently widely used. Medium-temperature flue gas flows in from the left side and out from the right side of the evaporation heat exchange chamber, while cold air flows in from the right side and out from the left side of the condensation heat exchange chamber. This parallel and counter-current flow of air and flue gas allows the heat pipes to transfer heat from the medium-temperature flue gas to the clean, low-temperature air, thus achieving the recovery and utilization of flue gas waste heat. This arrangement provides better heat exchange than arrangements where hot and cold fluids flow in parallel but in the same direction, but it is still not entirely satisfactory. Currently, the most widely used heat pipe heat exchangers still have a parallel flow arrangement of hot and cold fluids, which limits installation flexibility. On the other hand, heat pipe heat exchangers currently used in industrial applications generally use circular cross-section heat pipes, including gravity heat pipes and capillary heat pipes. In practical applications, heat pipes with circular cross-sections often experience significant pressure losses in fluid flow, requiring the fan to consume more electrical energy. Furthermore, to enhance heat transfer within the heat pipe and heat exchange chamber, fins are typically arranged on the outer wall of the heat pipe. Currently, commonly used fins are generally discontinuous circular or rectangular, or continuous rectangular, and are typically arranged at equal intervals or spirally wound with equal pitch along the evaporation or condensation sections of the heat pipe. Under practical application conditions, this results in poor fin efficiency and utilization.

[0003] Patent CN201020517703.9 discloses an elliptical heat pipe heat exchanger, comprising an elliptical heat pipe and several fins. This patent primarily addresses the low heat dissipation efficiency caused by excessively large or small aperture spacing on existing fins by arranging fins with different fin sizes. In this patent, the entire heat pipe is a uniform ellipse, and the adiabatic section lacks a twisting structure that would allow the evaporation and condensation sections to twist 90° along their long axes. The flow directions of the cold and hot fluids are parallel, resulting in lower heat exchange efficiency. Furthermore, the fins on the outer surface of the pipe in this patent are uniformly spaced continuous rectangular fins, significantly different from the design in this patent where the outer walls of the condensation and evaporation sections are arranged with denser fins in the middle and sparser fins at both ends, corresponding to the heat pipe cross-section. This design results in lower fin efficiency and utilization, and more severe ash accumulation when used for flue gas waste heat recovery. In addition to using an elliptical cross-section heat pipe, this patent also preferably provides airfoil-shaped and flattened oval cross-section heat pipes to further reduce pressure loss within the heat exchange cavity.

[0004] Patent CN 202011384805.2 discloses a flow-guided low-resistance heat pipe heat exchanger, including a heat pipe heat exchanger housing, a tube sheet, and a flow-guided low-resistance heat pipe bundle. The heat pipes used in the flow-guided low-resistance heat pipe bundle are also elliptical, and are mainly constructed by symmetrically welding metal strips of a certain width along the heat pipe axis to the elliptical base tube as flow guides. In this patent, the entire heat pipe is uniformly elliptical, and the heat pipe insulation section lacks a twisting structure that would allow the evaporation and condensation sections to twist 90° along their long axis. The flow directions of the cold and hot fluids are also arranged in parallel, resulting in lower heat exchange efficiency. Furthermore, in addition to using elliptical cross-section heat pipes, this patent also preferably provides airfoil and flattened circular cross-section heat pipes to further reduce pressure loss within the heat exchange cavity. Finally, the fins used in this patent are continuous fins along the direction of the heat pipe, and their main function is to guide flow and enhance heat transfer. This is significantly different from the design in this patent where the outer walls of the condensing section and the evaporation section are arranged with non-circular fins corresponding to the heat pipe cross-section in a form that is dense in the middle and sparse at both ends. Its fin efficiency and utilization rate are also lower. Summary of the Invention

[0005] To address the aforementioned technical problems, the objective of this invention is to provide a high-efficiency, low-resistance crossflow heat pipe heat exchanger. To achieve this objective, the present invention employs the following solution.

[0006] A high-efficiency, low-resistance crossflow heat pipe heat exchanger includes: a heat pipe bundle, an evaporation heat exchange chamber, an insulation layer, and a condensation heat exchange chamber;

[0007] The heat pipe bundle consists of several heat pipes arranged in a vertical array in a staggered pattern, and the heat pipe bundle penetrates the insulation layer.

[0008] Optionally, the heat pipe evaporation section is located inside the evaporation heat exchange chamber, and the heat pipe condensation section is located inside the condensation heat exchange chamber.

[0009] Optionally, the evaporation heat exchange chamber is composed of a chamber shell and a heat pipe evaporation section; the condensation heat exchange chamber is composed of a chamber shell and a heat pipe condensation section; wherein, the flow direction of the cold fluid in the condensation heat exchange chamber is perpendicular to the flow direction of the hot fluid in the evaporation heat exchange chamber.

[0010] Optionally, the cold fluid flows from the left end to the right end of the condensation heat exchange chamber, and the hot fluid flows from the front end to the rear end of the evaporation heat exchange chamber.

[0011] Optionally, fins are arranged on the outer walls of both the heat pipe condensation section and the heat pipe evaporation section.

[0012] Optionally, the outer walls of both the condensation section and the evaporation section are arranged with non-circular fins corresponding to the heat pipe cross-section, in a denser middle and sparser ends.

[0013] Optionally, the insulation layer consists of two layers of insulation plates with through holes and insulation material, the positions of the through holes corresponding to the arrangement positions of the heat pipe bundle, and the insulation section of the heat pipe bundle located inside the insulation layer and placed in the center; the condensation heat exchange cavity consists of a cavity shell and a heat pipe condensation section.

[0014] Optionally, the evaporation heat exchange chamber, the insulation layer, and the condensation heat exchange chamber are arranged sequentially from bottom to top.

[0015] Optionally, the heat pipe has a non-circular cross-section.

[0016] Optionally, the heat pipe cross-sectional shape is elliptical, airfoil-shaped, flattened round, or teardrop-shaped; the adiabatic section of the heat pipe is a twisted structure that can twist the long axis of the heat pipe cross-section by 90°.

[0017] Optionally, the flow direction of the main fluid in both the evaporation heat exchange chamber and the condensation heat exchange chamber is the same as the direction of the long axis of the heat pipe cross-section.

[0018] Optionally, the front end of the evaporation heat exchange chamber is provided with a hot fluid inlet, and the rear end of the evaporation heat exchange chamber is provided with a hot fluid outlet; the left end of the condensation heat exchange chamber is provided with a hot fluid inlet, and the right end of the condensation heat exchange chamber is provided with a hot fluid outlet.

[0019] Compared with the prior art, the present invention has the following technical effects:

[0020] 1. The cross-flow heat pipe heat exchanger of the present invention uses a non-circular cross-section heat pipe that is twisted in the adiabatic section, so that the flow direction of the hot and cold side fluids of the heat exchanger is the same as the long axis direction of the heat pipe cross-section. This can significantly reduce the pressure loss of the fluid in the heat exchange cavity, thereby significantly reducing the energy consumption of the fan. At the same time, it can also enhance the heat transfer process between the heat pipe and the heat exchange cavity, and significantly improve the heat exchange effect between the fluid in the heat exchange cavity and the heat pipe bundle.

[0021] 2. The outer walls of the condensation and evaporation sections are arranged with non-circular fins corresponding to the heat pipe cross-sections, which are dense in the middle and sparse at both ends. This fully utilizes the characteristics of high flow velocity in the mainstream fluid region and low flow velocity near the wall region, greatly improving the heat exchange efficiency of the fins and saving material usage. The staggered arrangement of the non-circular heat pipe bundles can further improve the compactness of the heat exchanger.

[0022] 3. Unlike the parallel flow arrangement of cold and hot fluids in commonly used heat pipe heat exchangers, the cross flow arrangement of cold and hot fluids provided by this invention not only improves heat exchange efficiency but also enhances the installation flexibility of the heat exchanger. Attached Figure Description

[0023] The accompanying drawings illustrate exemplary embodiments of the invention and, together with the description thereof, serve to explain the principles of the invention. These drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification.

[0024] Figure 1 This is a schematic diagram of the structure of a high-efficiency, low-resistance cross-flow heat pipe heat exchanger according to the present invention.

[0025] Figure 2(a) is Figure 1 Sectional view at point BB;

[0026] Figure 2(b) is Figure 1 A sectional view along line A1-A1;

[0027] Figure 2(c) is Figure 1 A sectional view along line A2-A2;

[0028] Figure 3 This is a schematic diagram of a non-circular cross-section heat pipe with variable-pitch fins.

[0029] Figure 4 This is a partial structural diagram of the insulation section of a non-circular cross-section heat pipe;

[0030] Figure 5 These are schematic diagrams of the cross-sectional shapes of three types of non-circular heat pipes;

[0031] Explanation of reference numerals in the attached figures:

[0032] 100-Condensation heat exchange chamber; 101-Heat pipe condensation section; 200-Insulation layer; 201-Heat pipe insulation section; 202-Through hole; 203-Insulation plate; 300-Evaporation heat exchange chamber; 301-Heat pipe evaporation section; 400-Fins; 501-Cold fluid inlet; 502-Cold fluid outlet; 601-Hot fluid inlet; 602-Hot fluid outlet. Detailed Implementation

[0033] The following is in conjunction with the appendix Figures 1 to 5 The present invention will be further described in detail below with reference to the embodiments. It is to be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present invention are shown in the accompanying drawings.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other. The technical solution of this invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] Unless otherwise stated, the exemplary embodiments / exemplifications shown are to be understood as providing exemplary features of various details that provide ways in which the technical concept of the invention can be implemented in practice. Therefore, unless otherwise stated, the features of the various embodiments / exemplifications may be additionally combined, separated, interchanged and / or rearranged without departing from the technical concept of the invention.

[0036] The use of crosshairs and / or shading in the accompanying drawings is generally used to clarify the boundaries between adjacent components. Thus, unless otherwise stated, the presence or absence of crosshairs or shading does not convey or indicate any preference or requirement for the specific material, material properties, dimensions, proportions, commonalities between the illustrated components, or any other characteristics, properties, etc., of the components. Furthermore, in the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.

[0037] When a component is referred to as being "on" or "above" another component, "connected to," or "joined to" another component, the component may be directly on, directly connected to, or directly joined to the other component, or there may be intermediate components. However, when a component is referred to as being "directly on" another component, "directly connected to," or "directly joined to" another component, there are no intermediate components. Therefore, the term "connection" can refer to a physical connection, an electrical connection, etc., and may or may not have intermediate components.

[0038] For descriptive purposes, the present invention may use spatial relative terms such as “below,” “under,” “below,” “down,” “above,” “above,” “higher,” and “side (e.g., in a “sidewall”)” to describe the relationship between one component and another component as shown in the accompanying drawings. In addition to the orientations depicted in the drawings, the spatial relative terms are also intended to encompass different orientations of the device during use, operation, and / or manufacture. For example, if the device in the drawings is flipped, a component described as “below” or “under” another component or feature would subsequently be positioned “above” said other component or feature. Thus, the exemplary term “below” can encompass both “above” and “below” orientations. Furthermore, the device may be otherwise positioned (e.g., rotated 90 degrees or in other orientations), thus interpreting the spatial relative descriptive terms used herein accordingly.

[0039] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0040] The present invention will now be described in detail with reference to the accompanying drawings.

[0041] In one embodiment, the present invention provides a high-efficiency, low-resistance crossflow heat pipe heat exchanger, comprising: a heat pipe bundle, an evaporation heat exchange chamber (300), an insulation layer (200), and a condensation heat exchange chamber (100).

[0042] The heat pipe bundle consists of several heat pipes arranged in a vertically arrayed, staggered pattern, penetrating the insulation layer (200). The heat pipes have a non-circular cross-section, and the heat pipe insulation section (201) is a twisted structure that allows the heat pipe cross-section to twist 90° along its long axis (see [reference]). Figure 4 ).

[0043] Using twisted, non-circular heat pipes in the adiabatic section ensures that the flow direction of the fluid on the hot and cold sides of the heat exchanger is the same as the long axis of the heat pipe cross-section. This can significantly reduce the pressure loss of the fluid in the heat exchange cavity, thereby significantly reducing the energy consumption of the fan. At the same time, it can also enhance the heat transfer process between the heat pipe and the heat exchange cavity, significantly improving the heat exchange effect between the fluid in the heat exchange cavity and the heat pipe bundle.

[0044] The heat pipe evaporation section (301) is located inside the evaporation heat exchange chamber (300), and the heat pipe condensation section (101) is located inside the condensation heat exchange chamber (100). The outer walls of both the heat pipe condensation section (101) and the heat pipe evaporation section (301) are arranged with non-circular fins (400) corresponding to the heat pipe cross-section in a denser middle and sparser end configuration (see...). Figure 3 ).

[0045] The outer walls of the condensation and evaporation sections are arranged with non-circular fins corresponding to the heat pipe cross-sections, which are dense in the middle and sparse at both ends. This fully utilizes the characteristics of high flow velocity in the mainstream fluid region and low flow velocity near the wall region, greatly improving the heat exchange efficiency of the fins and saving material usage. The staggered arrangement of the non-circular heat pipe bundles can further improve the compactness of the heat exchanger.

[0046] Reference Figure 1 , Figures 2(a) to 2(c) The evaporation heat exchange chamber (300) consists of a chamber shell and an evaporation section of a heat pipe bundle, wherein each heat pipe evaporation section (301) forms the evaporation section of the heat pipe bundle. Specifically, referring to Figure 2(c), a hot fluid inlet (601) is provided at the front end of the evaporation heat exchange chamber (300), and a hot fluid outlet (602) is provided at the rear end of the evaporation heat exchange chamber (300).

[0047] The insulation layer (200) consists of two layers of insulation plates (203) with through holes (202). The positions of the through holes correspond to the positions of the heat pipe bundle. The heat pipes pass through the through holes of the insulation plates and penetrate the insulation layer (200). The heat insulation section (201) of the heat pipe bundle is located inside the insulation layer (200). The insulation layer (200) is filled with air or with insulation materials such as glass wool and aerogel.

[0048] The insulating section of the heat pipe bundle is located inside the insulation layer and is placed in the center.

[0049] The condensing heat exchange chamber (100) is composed of a chamber shell and a condensing section of a heat pipe bundle. Each heat pipe condensing section (101) constitutes a condensing section of the heat pipe bundle. Specifically, as shown in Figure 2(a), a cold fluid inlet (501) is provided at the left end of the condensing heat exchange chamber, and a cold fluid outlet (502) is provided at the right end of the condensing heat exchange chamber.

[0050] Because the heat pipe insulation section (201) is designed as a torsion structure that allows the long axis of the heat pipe cross-section to twist by 90° (see... Figure 4 Therefore, the flow direction of the main fluid in both the evaporation heat exchange chamber (300) and the condensation heat exchange chamber (100) is the same as the direction of the major axis of the heat pipe cross-section (see [reference]). Figures 2(a) to 2(c) and Figure 3 Therefore, in practical applications, when fluid flows and exchanges heat in a heat pipe bundle with this cross-sectional shape, the pressure loss of both the cold and hot sides can be greatly reduced, thereby significantly reducing fan energy consumption. At the same time, the heat exchange performance of this type of heat pipe is significantly improved compared to commonly used circular cross-section heat pipes, and the staggered arrangement of non-circular heat pipe bundles can further improve the compactness of the heat exchanger.

[0051] Unlike the parallel flow arrangement of cold and hot fluids in commonly used heat pipe heat exchangers, the cold and hot fluids arranged in a cross-flow direction are provided in this invention (see...). Figures 2(a) to 2(c) Specifically, the cold fluid flows from the left end to the right end of the condensation heat exchange chamber (100), and the hot fluid flows from the front end to the rear end of the evaporation heat exchange chamber (300). This design not only improves the overall heat exchange efficiency of the heat pipe heat exchanger but also enhances the installation flexibility of the heat exchanger.

[0052] Preferably, the outer wall fins (400) of the heat pipe evaporation section (301) and condensation section (101) are arranged with variable fin spacing and are non-continuous, non-circular fins, or are arranged with variable pitch spiral fins (see...). Figure 3 This fin arrangement fully utilizes the characteristics of high flow velocity in the mainstream fluid region and low flow velocity near the wall region, greatly improving the heat exchange efficiency of the fins and saving material costs.

[0053] Preferably, the fins can also be arranged in a way that is denser away from the heat pipe insulation section (201) and sparser near the heat pipe insulation section (201) to improve the utilization efficiency of the fins.

[0054] Preferably, the heat pipe insulation section (201) is located inside the insulation layer (200). The insulation layer (200) uses only air insulation or is filled with glass wool or aerogel insulation material. The insulation layer (200) uses two or more insulation boards, and different types of insulation materials are filled between the insulation boards to obtain a better heat exchange effect.

[0055] Preferably, the heat pipe cross-sectional shape is any of elliptical, airfoil, flattened round, or teardrop shape (see...). Figure 5 ).

[0056] In the description of this specification, the references to terms such as "one embodiment / mode," "some embodiments / modes," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment / mode or example is included in at least one embodiment / mode or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / mode or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments / modes or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments / modes or examples described in this specification, as well as the features of different embodiments / modes or examples.

[0057] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0058] Those skilled in the art should understand that the above embodiments are merely for illustrating the present invention and are not intended to limit the scope of the invention. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of the present invention.

Claims

1. A high-efficiency, low-resistance cross-flow heat pipe heat exchanger, characterized in that, The cross-flow heat pipe heat exchanger includes a heat pipe bundle, an evaporation heat exchange chamber, and a condensation heat exchange chamber; wherein, the flow direction of the cold fluid in the condensation heat exchange chamber is perpendicular to the flow direction of the hot fluid in the evaporation heat exchange chamber; the main flow direction of the fluid in both the evaporation heat exchange chamber and the condensation heat exchange chamber is the same as the long axis direction of the heat pipe cross section. The cross-section of a single heat pipe in the heat pipe bundle is non-circular; Among them, the heat pipe insulation section is a twisted structure that twists the long axis of the heat pipe cross-section by 90°; The outer walls of both the heat pipe condensation section and the heat pipe evaporation section are arranged with non-circular fins corresponding to the heat pipe cross-section in a denser middle and sparser ends pattern. The use of twisted, non-circular cross-section heat pipes in the adiabatic section ensures that the flow direction of the fluid on the hot and cold sides of the heat exchanger is the same as the long axis of the heat pipe cross-section, which significantly reduces the pressure loss of the fluid in the heat exchange cavity, thereby significantly reducing the energy consumption of the fan. At the same time, it enhances the heat transfer process between the heat pipe and the heat exchange cavity, and significantly improves the heat transfer effect between the fluid in the heat exchange cavity and the heat pipe bundle. The outer walls of the condensing and evaporating sections are arranged with non-circular fins corresponding to the heat pipe cross-sections, with denser fins in the middle and sparser fins at both ends; the staggered arrangement of the non-circular heat pipe bundles further improves the compactness of the heat exchanger. The cross-flow heat pipe heat exchanger also includes a heat insulation layer; The evaporation heat exchange chamber, the insulation layer, and the condensation heat exchange chamber are arranged sequentially from bottom to top; The evaporation heat exchange chamber has a hot fluid inlet at the front end and a hot fluid outlet at the rear end; the condensation heat exchange chamber has a hot fluid inlet at the left end and a hot fluid outlet at the right end.

2. The cross-flow heat pipe heat exchanger according to claim 1, characterized in that, The heat pipe bundle consists of several heat pipes arranged in a vertical array in a staggered pattern.

3. The cross-flow heat pipe heat exchanger according to claim 2, characterized in that, The evaporation heat exchange chamber is composed of a chamber shell and a heat pipe evaporation section; the condensation heat exchange chamber is composed of a chamber shell and a heat pipe condensation section.

4. The cross-flow heat pipe heat exchanger according to claim 3, characterized in that, Fins are arranged on the outer walls of both the heat pipe condensation section and the heat pipe evaporation section.

5. The cross-flow heat pipe heat exchanger according to claim 4, characterized in that, The insulation layer consists of an insulation board and insulation material.

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