A bent tube heat dissipation and cold storage unit

Abstract

This utility model discloses a bent-tube heat exchanger unit with a cooling belt, comprising fins, a cooling belt unit shell, a bent-tube heat exchanger core, and a cover plate. One side of the cooling belt unit shell is open, allowing the bent-tube heat exchanger core to be embedded within it. The other side of the cooling belt unit shell is sealed to the cover plate, which has an inlet pipe and an outlet pipe. The bent-tube heat exchanger core is a two-pass heat exchanger, comprising two bent tubes with the same total length, number of bends, and bending radius. One end of each fin is connected to the cooling belt unit shell via thermally conductive adhesive or brazing, and the other end is welded to the bent tube. The bent-tube heat exchanger unit provided by this utility model has a small footprint, strong heat exchange capacity, and an internal heat exchanger with extremely high heat exchange efficiency and reliability, making it well-suited for automotive environments.

Description

Technical Field

[0001] This utility model relates to a vehicle-mounted refrigerated box cold storage unit, and more particularly to a bent tube heat dissipation strip cold storage unit. Background Technology

[0002] With the improvement of energy efficiency and the enhancement of environmental protection awareness, cold storage technology has been widely used in refrigeration, air conditioning, energy storage and other fields. The existing cold storage units of vehicle-mounted refrigerated boxes adopt the method of immersing the heat exchanger in phase change material. The capacity of this type of cold storage unit is limited by the volume and heat exchange capacity of the internal heat exchanger. Although the volume of general tube-fin heat exchangers is small, the cooling capacity is insufficient and the cold storage is slow. When using microchannel evaporators with strong cooling capacity, the heat exchanger has a large volume, high flow resistance, and a small amount of cold storage material can be added, resulting in a relatively low amount of cold energy that can be stored.

[0003] Bending tube heat exchangers, as a highly efficient heat exchange structure, are widely used in refrigeration systems due to their compact structure, large heat exchange area, and low flow resistance. In cold storage units, bending tube heat exchangers not only occupy a small volume but also significantly improve cold storage efficiency by optimizing parameters such as tube diameter, tube spacing, and flow path length. Furthermore, the flexibility of this type of heat exchanger allows it to adapt to cold storage devices of different shapes and sizes, further enhancing the system's integration and adaptability.

[0004] For general built-in evaporator-type cold storage units, this utility model provides a cold storage unit evaporator solution with small volume and strong heat exchange capacity, which is suitable for vehicle refrigerators. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a bent tube heat dissipation and cold storage unit that has a small volume, strong heat exchange capacity, and relatively uniform flow field.

[0006] To solve the above-mentioned technical problems, this utility model provides a bent-tube heat exchanger unit with a cooling belt, including fins, a cooling belt unit shell, a bent-tube heat exchanger core, and a cover plate. One side of the cooling belt unit shell is open, allowing the bent-tube heat exchanger core to be embedded within it. The other side of the cooling belt unit shell is sealed to the cover plate, which has an inlet pipe and an outlet pipe. The bent-tube heat exchanger core is a two-pass heat exchanger, comprising two bent tubes with the same total length, number of bends, and bending radius. The two bent tubes extend from both sides of the inlet pipe and enter from both sides of the outlet pipe, forming two parallel loops. One end of the fins is connected to the cooling belt unit shell by thermally conductive adhesive or brazing, and the other end of the fins is welded to the bent tubes.

[0007] Furthermore, the bent tube is formed by repeatedly bending the microchannel flat tube inward and outward, with the two microchannel flat tubes positioned symmetrically and the outer surface being a flat plane.

[0008] Furthermore, the fins are processed from aluminum foil to form a continuous wavy structure, and regular louvered windows are stamped out at the crests and troughs to form wave-shaped windowed fins. The wave-shaped windowed fins are cut into independent segments that match the length of the parallel straight tube segments of the microchannel flat tube. During assembly, the wave-shaped windowed fins are located in the middle of the parallel straight tube segments at both ends of the bent tube, and the crest and trough planes of the wave-shaped windowed fins are in contact with the flat plane of the microchannel flat tube.

[0009] Furthermore, each microchannel flat tube has 5 bends and 16 holes.

[0010] Furthermore, the aluminum foil has a thickness of 0.1 mm, and the wave height on the corrugated windowed fin is 3 mm, with a wave pitch of 5 mm.

[0011] Furthermore, the inlet pipe and outlet pipe are two metal aluminum pipes with openings on the sides.

[0012] Furthermore, the cover plate is provided with a sealing bolt and a filling port nut, and a filling hole is provided on the cover plate. The size of the filling hole is consistent with the outer diameter of the filling port nut, and the internal thread on the filling port nut is engaged with the sealing bolt for locking.

[0013] Furthermore, the sealing bolt is a threaded temperature sensor.

[0014] Compared with the prior art, the present invention has the following advantages: The bent tube heat dissipation and cold storage unit provided by the present invention has the following effects: 1. Extremely high heat exchange efficiency: The heat dissipation fins greatly increase the effective heat exchange area of ​​the cold storage unit, which not only accelerates the heat exchange between the refrigerant and the unit (cold storage process), but also accelerates the heat exchange between the unit and the inner cavity of the refrigerator (cold release process). 2. Uniform temperature effect: The heat dissipation fins connect the parallel bent tubes like "thermal bridges", which promotes the rapid lateral conduction of heat inside the unit, eliminates local temperature differences, and enables the refrigerant to undergo phase change synchronously and uniformly, thereby improving the overall cooling efficiency. 3. Excellent structural reliability and strength: The bent tube itself is a continuous rigid whole, avoiding potential leakage points caused by multi-section welding. Combined with the fixing effect of the heat dissipation fins, the entire heat exchange core forms a robust "truss" structure with excellent vibration and impact resistance, making it ideal for the harsh environment of vehicles; Uniform stress distribution: The planar bent structure can better adapt to the volume changes during the phase change process of the refrigerant, reducing periodic stress impacts on the pipeline; 4. Compact spatial layout: The flat shell combined with the flat bent tube and heat dissipation fins forms a very thin and efficient heat exchange unit, which can be installed close to the side or top of the inner liner of the cold storage shell, maximizing the saving of the effective volume inside the cold storage box. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the assembly of the bent tube heat dissipation and cold storage unit of this utility model; Figure 2 This is a schematic diagram of a single unit of the bent tube heat exchanger of this utility model; Figure 3 This is a schematic diagram of the assembly of the bent tube heat exchanger and the cold storage unit shell of this utility model. Figure 4 This is a schematic diagram of the assembly of the outer shell and cover plate of the cold storage unit of this utility model; Figure 5 This is a schematic diagram of the assembly of the cold storage unit and sensor of this utility model.

[0016] The diagram is marked as follows: 1. Fins; 2. Liquid outlet pipe; 3. Cooling unit shell; 4. Liquid inlet pipe; 5. Bent pipe heat exchanger core; 6. Cover plate; 7. Filler nut; 8. Sealing bolt. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a schematic diagram of the assembly of the bent tube heat dissipation and cold storage unit of this utility model. Figure 2 This is a schematic diagram of a single unit of the bent tube heat exchanger of this utility model.

[0019] Please see Figure 1 and Figure 2 The present invention provides a bent-tube heat exchanger cooling unit, comprising fins 1, an outlet pipe 2, a cooling unit housing 3, an inlet pipe 4, a bent-tube heat exchanger core 5, a cover plate 6, a filling port nut 7, and a sealing bolt 8. One side of the cooling unit housing 3 is open, allowing the bent-tube heat exchanger core 5 to be embedded and assembled within the housing. The other side of the cooling unit housing 3 is sealed to the cover plate 6. Figure 3 and Figure 4 As shown.

[0020] The fins 1 are heat sinks made of high thermal conductivity materials in any form that are attached to the outer shell to enhance heat exchange. The fins 1 need to be connected to the cold storage unit shell 3 by means of thermally conductive adhesive or brazing. During operation, the cold energy of the cold storage unit is transferred to the outside through the fins 1. The cold storage unit shell 3 is a pentahedral metal shell made of a high thermal conductivity material with openings in any direction. The opening direction is consistent with the installation direction of the cold storage unit. It is used to assemble the bent tube heat exchanger core 5. The bent tube heat exchanger core 5 is a two-pass heat exchanger. The bent tube is a microchannel flat tube. Fins 1 are welded between the upper and lower bent tubes during bending. During bending, the total length, number of bends, and bending radius of the two bent tubes are the same. Under this condition, the flow state of the refrigerant in the two bent tubes can be made as consistent as possible, thereby achieving the effect of uniform temperature distribution in the two passes. The inlet pipe 4 and outlet pipe 2 are two metal aluminum pipes with side openings, which act as manifolds in the heat exchanger. The two bent pipes pass out from both sides of the inlet pipe 4 and finally pass in from both sides of the outlet pipe 2, forming two parallel loops. The cover plate 6 has a filling hole, the size of which is the same as the outer diameter of the filling port nut 7, for assembling the filling port nut 7. After welding, the refrigerant can be added through this hole. The internal thread on the filling port nut 7 can be matched with the sealing bolt 8. After filling, it is sealed to ensure that the refrigerant does not flow out. The cover plate 6 and the cold storage unit housing 3 together form a sealed cavity, and the joint is sealed by laser welding.

[0021] Preferably, the cold storage unit housing 3 can be a one-piece stretched housing with the opening facing upwards, which can reduce welds and increase reliability.

[0022] The composition and installation of the bent-tube heat dissipation and cold storage unit are as follows: The main body is the heat exchanger core 5, which is formed by bending two microchannel flat tubes. In this embodiment, 38mm×2mm microchannel tubes are used, with a bending radius of 15 and 16 holes in each tube. Each tube has 5 bends, and the two tubes are symmetrically positioned. The outer surface is a flat plane to facilitate contact with the fins 1. The fins 1 are made of 0.1mm thick aluminum foil. Through precision stamping and stretching, the aluminum foil is first processed into a continuous wave-shaped structure with a specific wave height (e.g., 3mm) and wave pitch (e.g., 5mm). Regular louvered windows are stamped at the crests and troughs of the wave-shaped fins. These windows are not simple holes, but are flow guides that are stamped up and form a certain angle (usually 20°-30°) with the main airflow direction. This composite structure of "wave + window" can greatly disrupt the laminar boundary layer of the air and enhance turbulence, making it a highly efficient heat exchanger fin form.

[0023] The heat exchanger core 5 of the bent tube heat sink of this utility model adopts a stacked assembly. The corrugated window fins are cut into independent segments that match the length of the parallel straight pipe sections of the microchannel flat tube. During assembly, the corrugated window fins are located in the middle of the parallel straight pipe sections at both ends of the bent flat tube, and the crest and trough planes of the corrugated window fins are in contact with the upper and lower wide surfaces of the microchannel flat tube.

[0024] The assembled core is placed in a continuous brazing furnace under a controlled atmosphere. Under precise temperature control, the brazing filler melts and fills the interface between the flat tube and the fins through capillary action. After cooling, the flat tube and fins are brazed into a robust, integrated plate-shaped heat exchange core. This process forms a permanent metallurgical bond with extremely low thermal resistance and very high mechanical strength, capable of withstanding vehicle vibration. The cold storage unit housing 3 is a pentahedral metal shell made of a highly thermally conductive material, opening in any direction. The opening direction is consistent with the installation direction of the unit. In this embodiment, the opening direction of the cold storage unit housing 3 faces right, and the left side is an integrally stretched aluminum alloy shell. The size of its inner cavity is consistent with the outer size of the bent tube heat exchanger core 5. The bent tube heat exchanger core 5 is placed into the cold storage unit housing 3, with the inlet pipe 4 and outlet pipe 2 facing the right opening direction. Then, the cover plate 6 is installed. The cover plate 6 has three holes, which are respectively used for the inlet pipe 4 to pass through, the outlet pipe 2 to pass through, and for welding the filling port nut 7. The filling port nut 7 is a T-shaped nut with internal threads. The vertical part of the T extends into the filling hole on the cover plate 6. Then, the filling port nut 7 and the cover plate 6 are welded. After welding, the cold storage refrigerant can be added through this port. The internal thread on the nut can be matched with the sealing bolt. After filling, the sealing bolt 8 is used to seal the port to ensure that the cold storage refrigerant does not flow out. Figure 5 As shown. In this embodiment, the sealing bolt 8 is a threaded temperature sensor. While serving a sealing function, the sensor probe extending into the housing can monitor the temperature of the refrigerant in the cold storage unit in real time and provide feedback. The cover plate 6 and the cold storage unit housing 3 together form a sealed cavity, and the joint is sealed by laser welding. Finally, the fin 1 is a single piece of corrugated aluminum fin with open windows, which is attached to the surface of the cold storage unit with thermally conductive metal adhesive to enhance heat exchange.

[0025] This invention combines a microchannel flat tube with thin fins, maximizing the heat exchange area per unit volume and resulting in a highly compact structure. The use of aluminum alloy ensures strength while achieving lightweight construction; the integrally brazed core has no loose parts, providing excellent overall rigidity and strength, and its vibration and fatigue resistance far surpasses that of traditional copper tube-fin structures, perfectly meeting the requirements of automotive environments.

[0026] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications and improvements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A bend pipe heat radiation band cold storage unit characterized by comprising: It includes fins, a cold storage unit shell, a bent tube heat exchanger core, and a cover plate; one side of the cold storage unit shell is open, allowing the bent tube heat exchanger core to be embedded and assembled in the cold storage unit shell, and the other side of the cold storage unit shell is sealed to the cover plate, which is provided with an inlet pipe and an outlet pipe. The bent-tube heat exchanger core is a two-pass heat exchanger. The bent-tube heat exchanger core includes two bent tubes with the same total length, number of bends, and bending radius. The two bent tubes extend from both sides of the inlet pipe and finally enter from both sides of the outlet pipe, forming two parallel loops. One end of the fins is connected to the cold storage unit shell by thermally conductive adhesive or brazing, and the other end of the fins is welded to the bent tubes.

2. The bent tube heat dissipation and cold storage unit as described in claim 1, characterized in that, The bent tube is formed by repeatedly bending the microchannel flat tube inward and outward. The two microchannel flat tubes are symmetrically positioned and have a flat outer surface.

3. The bent tube heat dissipation and cold storage unit as described in claim 2, characterized in that, The fins are formed by processing aluminum foil into a continuous wavy structure, and regular louvered windows are stamped out at the crests and troughs to form wave-shaped windowed fins. The wave-shaped windowed fins are cut into independent segments that match the length of the parallel straight pipe sections of the microchannel flat tube. During assembly, the wave-shaped windowed fins are located in the middle of the parallel straight pipe sections at both ends of the bent tube, and the crest and trough planes of the wave-shaped windowed fins are in contact with the flat plane of the microchannel flat tube.

4. The bent tube heat dissipation and cold storage unit as described in claim 3, characterized in that, Each microchannel flat tube has 5 bends and 16 holes.

5. The bent tube heat dissipation and cold storage unit as described in claim 3, characterized in that, The aluminum foil has a thickness of 0.1 mm, and the wave height on the corrugated windowed fin is 3 mm, with a wave pitch of 5 mm.

6. The bent tube heat dissipation and cold storage unit as described in claim 1, characterized in that, The inlet and outlet pipes are two metal aluminum pipes with holes on the sides.

7. The bent tube heat dissipation and cold storage unit as described in claim 1, characterized in that, The cover plate is provided with a sealing bolt and a filling port nut. A filling hole is provided on the cover plate. The size of the filling hole is consistent with the outer diameter of the filling port nut. The internal thread on the filling port nut is engaged with the sealing bolt for locking.

8. The bent tube heat dissipation and cold storage unit as described in claim 7, characterized in that, The sealing bolt is a threaded temperature sensor.

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