Double-layer overflow pipe applied to heat exchange module

Abstract

A double-layer overflow pipe applied to a heat exchange module comprises an inner pipe used for overflowing, an opening in the upper end of the inner pipe is an overflow opening, and the double-layer overflow pipe is characterized in that the overflow opening is an inclined opening, an outer pipe used for guiding flow is arranged outside the inner pipe in a sleeved mode, an opening is formed in the upper end of the outer pipe, and an opening in the lower end of the outer pipe is an inflow opening allowing fluid to flow in. And a gap is formed between the outer pipe and the inner pipe. The double-layer overflow pipe has the advantages that the flowing path of fluid in the double-layer overflow pipe is in an inverted U shape, the inner pipe and the outer pipe can reduce the size of the double-layer overflow pipe, the space occupied by the double-layer overflow pipe in a heat exchange module is smaller, and the double-layer overflow pipe is more reasonable and flexible in layout; and the overflow ports of the inner pipes of the double-layer overflow pipes are inclined ports, so that each double-layer overflow pipe can overflow even if the heights of the inner pipes in the heat exchange module are different, and the layout flexibility of the double-layer overflow pipes in the heat exchange module is further improved.

Description

Technical Field

[0001] This utility model relates to the field of heat storage and heat exchange devices, and in particular to a double-layer overflow pipe used in heat exchange modules. Background Technology

[0002] Large-scale power storage systems can effectively address the instability of renewable energy, adjust peak and off-peak power grids, and improve the economic efficiency and stability of the power system. Currently, power grids often use thermal energy storage devices to store electrical energy. These devices typically use molten salt as the heat storage medium, converting low-cost electricity generated at night or surplus wind and solar power into high-temperature molten salt for storage. When electricity is needed, the high-temperature molten salt is fully exchanged with water to generate superheated steam, which is then used to generate electricity, thus achieving energy conservation.

[0003] Existing heat storage and heat exchange devices are divided into several layers using partition plates, namely, heat storage and heat exchange modules, heat exchange modules, and heat release and heat exchange modules from top to bottom. The heat exchange modules are located in the middle of the heat storage and heat exchange device. The lower-temperature molten salt near the bottom of the heat exchange module needs to overflow to the top of the next layer module through an overflow device. An existing overflow device used in the heat exchange module is shown in Chinese invention patent number CN202210608538.5 (authorization announcement number CN114838611B), entitled "A High-Temperature Heat Exchange and Heat Storage Unit and Structure and Device." The shell contains an overflow pipe and a filter box. The overflow pipe is an inverted U-shaped pipe. The filter box is located at the bottom of the shell, with filter holes on its peripheral wall and a flow hole on its top wall. The flow hole communicates with the overflow port of the overflow pipe. This overflow pipe can filter the molten salt near the bottom and allow it to flow to the next layer of high-temperature heat exchange and heat storage unit.

[0004] Currently, multiple inverted U-shaped overflow pipes need to be arranged in the heat exchange modules of thermal storage heat exchange devices. However, during actual operation, it is crucial to ensure that the height of all overflow pipes within each module is consistent to allow overflow from each pipe. If the height of some overflow pipes deviates, the higher-positioned overflow pipes will not overflow. Therefore, when operating the thermal storage heat exchange device under these conditions, the molten salt flow in the area corresponding to the overflow pipes that are not overflowing is nearly stopped. If multiple overflow pipes around this area also fail to overflow, this area becomes a heat exchange "dead zone." However, in actual manufacturing, due to variations in component machining precision and installation deviations (such as non-uniform settlement), it is difficult to guarantee the consistency of the actual installation height of the overflow pipes, thus making it impossible to avoid heat exchange "dead zones" and affecting the thermal storage capacity of the thermal storage heat exchange device. In addition, the inverted U-shaped overflow pipe is relatively large. Arranging multiple overflow pipes in the heat exchange module will occupy a lot of space, thereby affecting the layout of other components in the heat exchange module and increasing the difficulty of processing and assembling the heat storage and heat exchange device.

[0005] Therefore, further improvements are needed for the overflow pipe used in the heat exchange module. Summary of the Invention

[0006] The technical problem to be solved by this utility model is to provide a double-layer overflow pipe that is smaller in size and more flexible, which is used in heat exchange modules, in view of the above-mentioned existing technology.

[0007] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: the double-layer overflow pipe applied to the heat exchange module includes an inner pipe for overflow, the opening at the upper end of the inner pipe is an overflow port, characterized in that: the overflow port is an oblique opening, an outer pipe for guiding flow is sleeved on the outside of the inner pipe, the upper end of the outer pipe is an opening, the lower end of the outer pipe is an inlet for fluid to flow in, and there is a gap between the outer pipe and the inner pipe.

[0008] To enhance the fluid collection capacity of the double-layer overflow pipe, a filter box is preferably included for fluid collection. The surface of the filter box has multiple through-holes for fluid inflow. The lower end of the outer pipe communicates with the upper end of the filter box, and the lower end of the inner pipe passes through the bottom of the filter box. The fluid at the bottom first collects in the filter box through the multiple through-holes, and then flows into the double-layer overflow pipe through the inlet of the outer pipe, allowing the fluid at the bottom to overflow downwards. Therefore, the filter box increases the flow area during fluid collection, thereby improving the fluid collection capacity of the double-layer overflow pipe.

[0009] To ensure communication between the lower end of the outer tube and the upper end of the filter box, preferably, the upper end of the filter box has a connecting hole with the same diameter as the inner diameter of the outer tube. This connecting hole communicates with the inlet at the lower end of the outer tube. The connecting hole's diameter is the same as the inner diameter of the outer tube, the inlet of the outer tube is aligned with the connecting hole, and the lower end of the outer tube is placed on the upper end of the filter box. The connection between the outer tube and the filter box is then welded, thereby achieving communication between the lower end of the outer tube and the upper end of the filter box.

[0010] To ensure that only fluid can flow into the filter box, the aperture of the through-hole in the filter box is preferably 1-2 mm. If the through-hole is too small, the fluid will flow into the filter box slowly; if the through-hole is too large, solids will flow into the double-layer overflow pipe along with the fluid.

[0011] To improve the overflow capacity of the double-layer overflow pipe, preferably, the flow area of ​​the outer pipe is 2 to 3 times that of the inner pipe. The flow area of ​​the outer pipe is the cross-section of the outer pipe minus the cross-section of the inner pipe. Compared with the existing inverted U-shaped overflow pipe, this double-layer overflow pipe increases the overflow capacity by 2 to 3 times, thus improving the overflow capacity of the double-layer overflow pipe.

[0012] Compared with the prior art, the advantages of this utility model are as follows: The double-layer overflow pipe has an inner pipe and an outer pipe. The gap between the inner and outer pipes forms a channel for fluid to flow in. The fluid at the bottom flows into the channel from the inlet of the outer pipe and then flows out of the double-layer overflow pipe through the overflow port of the inner pipe. The flow path of the fluid in the double-layer overflow pipe is inverted U-shape. The inner and outer pipes can reduce the volume of the double-layer overflow pipe, making the space occupied by the double-layer overflow pipe in the heat exchange module smaller, and the layout of the double-layer overflow pipe is more reasonable and flexible. In addition, the overflow port of the inner pipe of the double-layer overflow pipe is oblique. The oblique opening can reduce the gradient of the overflow flow rate as the fluid level rises. Therefore, even if the height of each inner pipe in the heat exchange module is not consistent, it can be ensured that each double-layer overflow pipe can overflow, thereby improving the flexibility of the layout of the double-layer overflow pipe in the heat exchange module. Attached Figure Description

[0013] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model. Detailed Implementation

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0015] like Figure 1 The image shown is the preferred embodiment of this utility model.

[0016] In this embodiment, the double-layer overflow pipe is used in the heat exchange module of the thermal storage heat exchange device to overflow the bottom molten salt in the cover heat exchange module to the top of the next heat exchange module. For example... Figure 1 As shown, the double-layer overflow pipe of this embodiment includes an inner pipe 1 for overflow, an outer pipe 2 for guiding flow, and a filter box 3 for collecting fluid. The upper opening of the inner pipe 1 is an overflow port 11, which is oblique. The outer pipe 2 is sleeved on the outside of the inner pipe 1. The upper end of the outer pipe 2 is open, and the lower opening of the outer pipe 2 is an inlet for molten salt to flow in. There is a gap between the outer pipe 2 and the inner pipe 1. The surface of the filter box 3 is provided with multiple through holes (not shown) for molten salt to flow in. The diameter of the through holes is 1-2 mm. The lower end of the outer pipe 2 is connected to the upper end of the filter box 3. The lower end of the inner pipe 1 passes through the bottom of the filter box 3. Specifically, the upper end of the filter box 3 is provided with a connecting hole. The diameter of the connecting hole is the same as the inner diameter of the outer pipe 2. The connecting hole is connected to the inlet at the lower end of the outer pipe 2.

[0017] The workflow of this embodiment is as follows: The molten salt at a lower temperature at the bottom of the heat exchange module will first be collected in the filter box 3 through the through hole, and then flow into the outer tube 2 through the connection hole and the inlet. The molten salt flows upward in the outer tube 2, and then flows downward into the inner tube 1 through the overflow port 11. Finally, it flows from the lower end of the inner tube 1 to the top of the next heat exchange module, thereby completing the overflow process of the molten salt.

Claims

1. A double-layer overflow pipe for use in a heat exchange module, comprising an inner pipe (1) for overflow, wherein the opening at the upper end of the inner pipe (1) is an overflow port (11), characterized in that: The overflow port (11) is oblique, and an outer tube (2) for guiding flow is sleeved on the outside of the inner tube (1). The upper end of the outer tube (2) is open, and the lower end of the outer tube (2) is an inlet for fluid to flow in. There is a gap between the outer tube (2) and the inner tube (1).

2. The double-layer overflow pipe according to claim 1, characterized in that: It also includes a filter box (3) for collecting fluid, the surface of which is provided with a plurality of through holes for fluid to flow in, the lower end of the outer tube (2) is connected to the upper end of the filter box (3), and the lower end of the inner tube (1) passes through the bottom of the filter box (3).

3. The double-layer overflow pipe according to claim 2, characterized in that: The filter box (3) has a connection hole at its upper end. The diameter of the connection hole is the same as the inner diameter of the outer tube (2). The connection hole is connected to the inlet at the lower end of the outer tube (2).

4. The double-layer overflow pipe according to claim 2, characterized in that: The diameter of the through hole in the filter box (3) is 1-2 mm.

5. The double-layer overflow pipe according to any one of claims 1 to 4, characterized in that: The flow area of ​​the outer pipe (2) is 2 to 3 times that of the flow area of ​​the inner pipe (1).

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