Collector tube combined efficient tubular countercurrent heat exchanger and method

Abstract

The invention discloses a collector tube combined efficient tubular countercurrent heat exchanger and a method. Comprising a high-pressure liquid collecting pipe A (1), a high-pressure liquid collecting pipe B (2), a low-pressure liquid collecting pipe A (3), a low-pressure liquid collecting pipe B (4), an inner core heat exchange pipe (5) and an outer core heat exchange pipe (6). The high-pressure liquid collecting pipes A and B are embedded in the low-pressure liquid collecting pipes A and B respectively to form two liquid collecting assemblies, the inner core heat exchange pipe (5) is embedded in the outer core heat exchange pipe (6) to form a heat exchange assembly, and the two liquid collecting assemblies are connected through the heat exchange assembly. Two ends of the outer core heat exchange tube (6) are respectively communicated with an interlayer cavity between the high-pressure liquid collecting tube A and the low-pressure liquid collecting tube A and an interlayer cavity between the high-pressure liquid collecting tube B and the low-pressure liquid collecting tube B; the two ends of the inner core heat exchange tube (5) penetrate through the low-pressure liquid collecting tubes A and B to be communicated with inner cavities of the high-pressure liquid collecting tubes A and B. The multi-time enhanced heat exchange of fluid flowing into the cavity, flowing into the core body and flowing out of the cavity is realized, so that the heat exchange efficiency is improved.

Description

Technical Field

[0001] The present invention belongs to the field of aviation and aerospace integrated thermal management technology, and in particular relates to a high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting pipe and a method thereof. Background Art

[0002] With the continuous improvement of heat exchanger performance in aerospace, there is an urgent need for heat exchangers to operate stably and efficiently under complex environmental conditions. Heat exchangers are required to have good heat transfer performance and stability to meet the heat exchange conditions under various temperature differences and variable working conditions. Traditional shell-and-tube heat exchangers assemble the heat pipes in the middle of the two end plates and wrap the shell around the heat pipe bundle to form the product as a whole. High-pressure medium flows in the heat pipes, and low-pressure medium flows in the area between the heat pipes and the shell. In order to meet the process requirements of the product, traditional shell-and-tube heat exchangers are generally cylindrical in structure. The volume space occupied by the product is relatively large, and the flow channel structure is limited. The product flow channel is generally designed as a reverse cross flow or forward cross flow structure. The product heat exchange efficiency is relatively low and the power-to-weight ratio is relatively small. Summary of the Invention

[0003] The purpose of the present invention is to provide a high-efficiency shell-and-tube counterflow heat exchanger and method with a combined manifold. This invention enables a pure counterflow arrangement of the shell-and-tube heat exchanger, further improving the pressure-bearing capacity of the high-pressure chamber. By designing manifolds at the inlet and outlet locations of the cold and hot side media, multiple enhanced heat exchanges are achieved at the fluid inlet, outlet, and outlet locations, thereby improving heat exchange efficiency.

[0004] The technical solution of the present invention is: a high-efficiency shell-and-tube countercurrent heat exchanger with a liquid collecting pipe combination, comprising a high-pressure liquid collecting pipe A, a high-pressure liquid collecting pipe B, a low-pressure liquid collecting pipe A, a low-pressure liquid collecting pipe B, an inner core heat exchange pipe and an outer core heat exchange pipe; the high-pressure liquid collecting pipes A and B are respectively nested in the low-pressure liquid collecting pipes A and B to form two liquid collecting components, the inner core heat exchange pipe is nested in the outer core heat exchange pipe to form a heat exchange component, and the two liquid collecting components are connected via the heat exchange component; the two ends of the outer core heat exchange pipe are respectively connected to the interlayer cavity between the high and low pressure liquid collecting pipes A, and the interlayer cavity between the high and low pressure liquid collecting pipes B; the two ends of the inner core heat exchange pipe are respectively connected to the inner cavity of the high-pressure liquid collecting pipes A and B through the low-pressure liquid collecting pipes A and B.

[0005] In the aforementioned high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting pipe, the open ends of the low-pressure liquid collecting pipes A and B are provided with coaxial positioning components, and the closed ends of the high-pressure liquid collecting pipes A and B pass through the closed ends of the low-pressure liquid collecting pipes A and B and abut against the coaxial positioning components.

[0006] In the aforementioned high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting pipe, the coaxial positioning assembly includes a positioning ring, the outer periphery of which is connected to the support ring via connecting ribs; the inner conical surface of the positioning ring abuts against the closed end of the high-pressure liquid collecting pipe A / B, and the support ring cooperates with the inner wall surface of the open end of the low-pressure liquid collecting pipe A / B.

[0007] In the aforementioned high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting pipe, guide limit platforms are provided on the outer sides of the closed ends of the low-pressure liquid collecting pipes A and B, and limit convex rings are provided on the tube bodies of the high-pressure liquid collecting pipes A and B; after the closed ends of the high-pressure liquid collecting pipes A and B are respectively abutted against the coaxial positioning components, the end faces of the limit convex rings and the end faces of the guide limit platforms are combined and brazed and fixed.

[0008] In the aforementioned high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting pipe, both ends of the inner core heat exchange tube are fixed to the tube walls of the high-pressure liquid collecting pipes A and B by brazing, and both ends of the outer core heat exchange tube are fixed to the tube walls of the low-pressure liquid collecting pipes A and B by brazing.

[0009] In the aforementioned high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting pipe, both end surfaces of the inner core heat exchange tube protrude from the inner cavity wall of the high-pressure liquid collecting pipes A and B by 0.5mm to 1mm, and both end surfaces of the outer core heat exchange tube protrude from the inner cavity wall of the low-pressure liquid collecting pipes A and B by 0.5mm to 1mm.

[0010] In the aforementioned high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting pipe, the two end faces of the inner core heat exchange pipe are respectively fitted with the inner cavity walls of the high-pressure liquid collecting pipes A and B; the two end faces of the outer core heat exchange pipe are respectively fitted with the inner cavity walls of the low-pressure liquid collecting pipes A and B.

[0011] In the heat exchange method of the aforementioned manifold combined high-efficiency shell-and-tube countercurrent heat exchanger, the hot side medium flows into the inner cavity of the high-pressure manifold A, and is introduced into the inner cavity of the high-pressure manifold B through the inner core heat exchange tube before flowing out; the cold side medium flows into the interlayer cavity between the high and low pressure manifolds B, and is introduced into the interlayer cavity between the high and low pressure manifolds A through the interlayer channel between the inner and outer core heat exchange tubes before flowing out.

[0012] The advantages of the present invention are: the present invention designs a high-efficiency countercurrent heat exchanger structure, breaks the technical bottleneck of the difficult arrangement of the countercurrent structure of the traditional shell-and-tube heat exchanger, strengthens the heat exchange capacity of the inter-tube cavity, expands the pressure range of the high-pressure medium, realizes a new inventive structure of multiple heat exchanges between high-pressure and low-pressure media, and improves the heat exchange efficiency.

[0013] The present invention uses the structure of the inner core heat exchange tube, the inner core heat exchange tube is assembled to the low-pressure collecting tube A, the high-pressure collecting tube A and the low-pressure collecting tube B, the high-pressure collecting tube B in sequence, the outer core heat exchange tube is assembled to the low-pressure collecting tube A and the low-pressure collecting tube B, and is brazed to form an integrated structure, forming a high-pressure medium flow channel and a low-pressure medium flow channel respectively, forming a high-efficiency pure countercurrent heat exchange structure; breaking the technical bottleneck of the difficult countercurrent arrangement of the traditional shell and tube heat exchanger: the invention connects the high-pressure collecting tube A and the low-pressure collecting tube A, the high-pressure collecting tube B and the low-pressure collecting tube B by brazing or electron beam welding , forming flow channels for cold and hot side media respectively. The high-pressure medium flows in the inner core heat exchange tube, and the low-pressure medium flows in the sandwich layer between the inner core heat exchange tube and the outer core heat exchange tube, which increases the disturbance of the medium in the sandwich layer and strengthens the heat exchange. When the medium flows through the low-pressure manifold A, it exchanges heat with the high-pressure medium after heat exchange for the first time. When the hot side medium flows through the low-pressure manifold B, it exchanges heat with the low-temperature medium after heat exchange again, which improves the heat exchange efficiency and realizes pure countercurrent and efficient heat exchange, reduces the redundancy of the entire aircraft fuel, environmental control system, and engine lubricating oil, and increases system reliability.

[0014] The present invention realizes multiple heat exchanges between high-pressure media and low-pressure media: The present invention proposes an enhanced heat transfer scheme under high-pressure working conditions, which is based on traditional shell-and-tube heat exchanger technology. First, high-pressure collecting pipe A and low-pressure collecting pipe A are set at the inlet to realize the initial heat exchange of the fluid. The fluid flows into the inner core heat exchange tube and the outer core heat exchange tube for further heat exchange, and finally flows out after heat exchange through the low-pressure collecting pipe B and the high-pressure collecting pipe B. The fluid realizes multiple convection enhanced heat exchange in a limited space. The efficiency is improved by more than 5% compared with the traditional shell-and-tube heat exchanger through countercurrent arrangement and multiple heat exchanges.

[0015] The present invention broadens the pressure-bearing range of high-pressure media: traditional shell-and-tube heat exchangers require the arrangement of spherical sealing components to achieve the function of collecting and diverting high-pressure media. This invention creatively eliminates the traditional spherical sealing structure and replaces the sealing structure with high-pressure collecting pipes A and B. Due to the limitations of the shell-and-tube arrangement, the pressure-bearing capacity of the original spherical cover is relatively low. The collecting pipe structure proposed in this invention can be adaptively adjusted according to the medium pressure resistance index, thereby increasing the pressure resistance of the lightweight heat exchanger from 15MPa to more than 25MPa, thereby broadening the medium pressure-bearing capacity.

[0016] The present invention has a compact structure and a high power-to-weight ratio: to facilitate the welding process of the shell-and-tube heat exchanger, traditional shell-and-tube heat exchangers are all cylindrical structures, the heat exchangers are large in size and relatively low in efficiency. This structure can be designed as a square structure according to the compact layout space on the machine, effectively reducing the spatial layout of the product and improving the compactness of the product. The power-to-weight ratio is increased by more than 15% compared with traditional shell-and-tube heat exchangers. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1It is a schematic structural diagram of the present invention;

[0018] Figure 2 It is a schematic diagram of the coaxial positioning component structure;

[0019] Figure 3 It is a schematic diagram of the internal structure of the present invention;

[0020] Figure 4 yes Figure 3 A-direction schematic diagram. DETAILED DESCRIPTION

[0021] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection of the present invention.

[0022] The features and illustrative embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed in order to provide a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is in no way limited to any specific arrangement and method proposed below, but rather encompasses any improvements, replacements, and modifications to structures, methods, and devices without departing from the spirit of the present invention. In the accompanying drawings and the following description, well-known structures and techniques are not shown to avoid unnecessary ambiguity in the present invention.

[0023] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other, and the embodiments can refer to and quote each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] Example 1. A high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting pipe and method, see Figures 1-4The heat exchanger comprises a high-pressure manifold A1, a high-pressure manifold B2, a low-pressure manifold A3, a low-pressure manifold B4, an inner heat exchange tube 5, and an outer heat exchange tube 6. The high-pressure manifolds A and B are nested within the low-pressure manifolds A and B, respectively, forming two manifold assemblies. The inner heat exchange tube 5 is nested within the outer heat exchange tube 6, forming a heat exchange assembly. The two manifold assemblies are connected via the heat exchange assembly. The ends of the outer heat exchange tube 6 communicate with the interlayer cavity between the high- and low-pressure manifolds A and B, respectively. The ends of the inner heat exchange tube 5 pass through the low-pressure manifolds A and B, respectively, and communicate with the inner cavities of the high-pressure manifolds A and B. This structure achieves a pure countercurrent arrangement for the heat exchanger, boasting a compact structure and high heat exchange efficiency, which is 5% higher than that of traditional shell-and-tube heat exchangers.

[0025] The open ends of the aforementioned low-pressure manifolds A and B are equipped with coaxial positioning assemblies 7. The closed ends of the high-pressure manifolds A and B pass through the corresponding closed ends of the low-pressure manifolds A and B and abut against the coaxial positioning assemblies 7. This structure improves assembly processability, and the positioning assemblies define the assembly position, thus preventing errors.

[0026] The aforementioned coaxial positioning assembly 7 comprises a positioning ring 7.1, the outer periphery of which is connected to a support ring 7.3 via connecting ribs 7.2. The inner conical surface of the positioning ring 7.1 abuts against the closed end of the high-pressure manifold A / B, while the support ring 7.3 engages with the inner wall surface of the open end of the low-pressure manifold A / B. This positioning assembly provides support for the manifolds, avoiding a cantilevered structure, improving the product's vibration resistance and extending its lifespan by over a year.

[0027] The closed ends of the aforementioned low-pressure manifolds A and B are each equipped with a guide stop 8, while the high-pressure manifolds A and B are fitted with a stop collar 9. After the closed ends of the high-pressure manifolds A and B abut against the coaxial positioning assembly 7, the end faces of the stop collar 9 and the guide stop 8 are brazed together. This mating structure limits the position of the positioning assembly, reduces the design of positioning tooling, and improves production efficiency. It also enables integrated brazing of the components, avoiding the strength loss caused by repeated fusion welding, and increasing the root strength of the joint by 8%.

[0028] Both ends of the inner heat exchange tube 5 are brazed to the walls of the high-pressure headers A and B, respectively. Both ends of the outer heat exchange tube 6 are brazed to the walls of the low-pressure headers A and B. This structure simultaneously arranges flow channels for both hot-side and cold-side media, securing the heat exchange tubes through the headers at both ends, and avoiding the stress concentration caused by multiple welding processes in traditional heat exchangers.

[0029] Both ends of the inner heat exchange tube 5 protrude 0.5mm to 1mm from the inner wall of the high-pressure manifolds A and B, while both ends of the outer heat exchange tube 6 protrude 0.5mm to 1mm from the inner wall of the low-pressure manifolds A and B. This dimensioning allows for capillary action in small gaps, ensuring a full brazing seam and improving brazing reliability.

[0030] The inner heat exchange tube 5 is fitted at both ends to the inner walls of the high-pressure manifolds A and B, respectively. The outer heat exchange tube 6 is fitted at both ends to the inner walls of the low-pressure manifolds A and B, respectively. The inner and outer heat exchange tubes are brazed together through the manifolds at both ends, ensuring the rigidity and durability of the tubes.

[0031] The heat exchange method of the aforementioned high-efficiency shell-and-tube counterflow heat exchanger with combined manifolds is as follows: the hot-side medium flows into the inner cavity of high-pressure manifold A1, passes through the inner core heat exchange tube 5, and is introduced into the inner cavity of high-pressure manifold B2 before flowing out; the cold-side medium flows into the interlayer cavity between the high- and low-pressure manifolds B, passes through the interlayer channel between the inner and outer core heat exchange tubes, and is introduced into the interlayer cavity between the high- and low-pressure manifolds A2 before flowing out. The innovative channel arrangement of the hot-side and cold-side media achieves a pure counterflow structure, while simultaneously achieving efficient heat exchange through three heat exchanges, increasing heat exchange efficiency by over 5%, a significant improvement over traditional shell-and-tube heat exchangers.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should all be covered by the scope of protection of the present invention.

Claims

1. A high-efficiency shell-and-tube countercurrent heat exchanger with a liquid collecting tube combination, characterized in that: The invention comprises a high-pressure liquid collecting pipe A (1), a high-pressure liquid collecting pipe B (2), a low-pressure liquid collecting pipe A (3), a low-pressure liquid collecting pipe B (4), an inner core heat exchange pipe (5) and an outer core heat exchange pipe (6); the high-pressure liquid collecting pipes A and B are respectively nested in the low-pressure liquid collecting pipes A and B to form two liquid collecting components, the inner core heat exchange pipe (5) is nested in the outer core heat exchange pipe (6) to form a heat exchange component, and the two liquid collecting components are connected via the heat exchange component; the two ends of the outer core heat exchange pipe (6) are respectively connected to the interlayer cavity between the high-pressure and low-pressure liquid collecting pipes A and the interlayer cavity between the high-pressure and low-pressure liquid collecting pipes B; the two ends of the inner core heat exchange pipe (5) pass through the low-pressure liquid collecting pipes A and B to be connected to the inner cavity of the high-pressure liquid collecting pipes A and B.

2. The high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting tube according to claim 1 is characterized in that: The open ends of the low-pressure collecting pipes A and B are provided with coaxial positioning components (7), and the closed ends of the high-pressure collecting pipes A and B pass through the closed ends of the low-pressure collecting pipes A and B and abut against the coaxial positioning components (7).

3. The high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting tube according to claim 2 is characterized in that: The coaxial positioning assembly (7) comprises a positioning ring (7.1), the outer periphery of which is connected to a support ring (7.3) via a connecting rib (7.2); the inner conical surface of the positioning ring (7.1) abuts against the closed end of the high-pressure collecting pipe A / B, and the support ring (7.3) cooperates with the inner wall surface of the open end of the low-pressure collecting pipe A / B.

4. The high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting tube according to claim 2 is characterized in that: The closed ends of the low-pressure liquid collecting pipes A and B are both provided with guide limit platforms (8) on their outer sides, and the high-pressure liquid collecting pipes A and B are provided with limit convex rings (9) on their tube bodies; after the closed ends of the high-pressure liquid collecting pipes A and B are correspondingly abutted against the coaxial positioning components (7), the end faces of the limit convex rings (9) and the end faces of the guide limit platforms (8) are combined and brazed and fixed.

5. The high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting tube according to claim 1 is characterized in that: Both ends of the inner core heat exchange tube (5) are fixed to the tube walls of the high-pressure collecting tubes A and B respectively by brazing, and both ends of the outer core heat exchange tube (6) are fixed to the tube walls of the low-pressure collecting tubes A and B by brazing.

6. The high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting tube according to claim 5 is characterized in that: Both end surfaces of the inner core heat exchange tube (5) protrude from the inner cavity wall surface of the high-pressure collecting tubes A and B by 0.5 mm to 1 mm, and both end surfaces of the outer core heat exchange tube (6) protrude from the inner cavity wall surface of the low-pressure collecting tubes A and B by 0.5 mm to 1 mm.

7. The high-efficiency shell-and-tube countercurrent heat exchanger with a combined liquid collecting tube according to claim 1, characterized in that: The two end surfaces of the inner core heat exchange tube (5) are respectively fitted with the inner cavity wall surfaces of the high-pressure collecting tubes A and B; the two end surfaces of the outer core heat exchange tube (6) are respectively fitted with the inner cavity wall surfaces of the low-pressure collecting tubes A and B.

8. A heat exchange method using a liquid collecting tube combined high-efficiency shell-and-tube countercurrent heat exchanger as claimed in any one of claims 1 to 7, characterized in that: The hot side medium flows into the inner cavity of the high pressure collecting tube A (1), and is introduced into the inner cavity of the high pressure collecting tube B (2) through the inner core heat exchange tube (5), and then flows out; the cold side medium flows into the interlayer cavity between the high and low pressure collecting tubes B, and is introduced into the interlayer cavity between the high and low pressure collecting tubes A (2) through the interlayer channel between the inner and outer core heat exchange tubes, and then flows out.

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