CN115164630A - A rotary enhanced heat exchange phase change heat storage device - Google Patents

Abstract

The invention relates to a rotary enhanced heat exchange phase change heat storage device, comprising a heat storage shell, a rotating device, a phase change heat storage unit and a heat exchange flow channel, the heat storage shell comprises a heat storage shell, and the heat storage shell is provided with There is a heat exchange medium inlet and a heat exchange medium outlet, the rotating device includes a first turntable, a second turntable and a rotating shaft, the phase change heat storage unit includes a heat storage tube and a phase change material assembly, and the heat storage tube includes an inner tube of the heat storage tube and an outer tube of the heat storage tube. and the tube wall of the heat storage tube, the heat exchange flow channel includes a first fluid channel and a second fluid channel. Compared with the prior art, the invention has the advantages of high heat exchange efficiency, good heat exchange uniformity, small flow resistance, small pressure drop of the phase change heat storage device, simple device, wide application and the like.

Description

A rotary enhanced heat exchange phase change heat storage device

technical field

The invention relates to the technical field of heat storage, in particular to a rotary enhanced heat exchange phase change heat storage device.

Background technique

Low-cost, stable and reliable renewable energy technology is the key for China to achieve the two goals of "carbon peaking" and "carbon neutrality" in the future. However, solar energy, wind energy and other renewable energy sources generally have the characteristics of volatility and intermittence, resulting in the contradiction between the supply and demand of renewable energy in terms of time, space and intensity. In order to ensure the flexibility and stability of the operation of the renewable energy system and improve the energy utilization rate, it is necessary to consider various energy storage technologies such as electricity storage, heat storage, and cold storage. In energy storage technology, heat storage technology stores energy in the form of thermal energy. As of November 2020, the scale of the global heat storage system is about 234GWh. Great promotion potential. In addition, more than 90% of the world's energy is eventually utilized in the form of thermal energy, so the heat storage technology also has a broader application space. Heat storage technology can be divided into sensible heat heat storage, latent heat heat storage and thermochemical heat storage according to the form of heat storage. Latent heat storage, also known as phase change heat storage, is a method of storing and releasing thermal energy by utilizing the characteristics of phase change materials to absorb and release latent heat of phase change during the phase change process. Compared with sensible heat heat storage and thermochemical heat storage, phase change heat storage has the advantages of high energy storage density, constant temperature heat storage and release, convenient temperature control, and wide application range. Therefore, phase change heat storage technology has wide application and development prospects in the fields of waste heat recovery and utilization, solar heating, battery thermal management systems, green buildings, solar thermal power plants, etc. The phase change material plays a decisive role in the application of phase change heat storage technology.

The phase change heat storage device is composed of a plurality of phase change heat storage units and heat exchange flow channels. The heat exchange medium flows in the flow channels, and exchanges heat with the phase change material in the phase change heat storage unit through the heat exchange wall surface, thereby realizing heat storage and release.

For the phase change heat storage unit, its shape is various, including rectangular, spherical, cylindrical, annular and so on. The heat storage and release characteristics of different shapes of phase change heat storage devices are quite different. It is very important to select a phase change heat storage unit with an appropriate shape to design an efficient phase change heat storage system. Relevant scholars have studied the melting characteristics of phase change heat storage devices with rectangular, cylindrical and concentric casings with the same volume and heat exchange area, and compared the performance parameters such as the average convective heat transfer coefficient and melting time. In this case, the concentric sleeve type requires the least time, and this advantage is more obvious as the loading of the phase change material increases. Therefore, due to the high heat exchange efficiency and compact structure, compared with other shapes, the sleeve-type phase change heat storage device has a broader application prospect.

For the heat exchange channel, its structure is the backbone of the phase change energy storage technology. In order to improve the heat exchange effect, most of the current work considers increasing the heat exchange area and increasing the heat exchange uniformity of the phase change heat storage device by adding fins, using corrugated plates or porous structures. However, increasing the heat exchange area will increase the complexity of the phase change heat storage container, increase the manufacturing cost, and further reduce the filling amount of the phase change material. In addition, the main heat exchange components of the traditional phase change regenerator are stationary. In order to increase the total heat exchange coefficient, the Reynolds number is often increased by increasing the flow rate of the heat exchange medium, thereby improving the heat exchange effect. However, due to the quadratic relationship between the resistance and the flow velocity, the pressure drop also increases when the flow velocity of the heat exchange medium is increased, so a balance can only be sought between the flow velocity and the pressure drop. In addition, when the heat exchange medium flows along the process, because the heat exchange temperature difference between the heat exchange medium and the phase change material is getting smaller and smaller, it is easy to cause the phase change heat storage unit near the outlet of the heat accumulator to be unable to effectively store and release heat, and the phase change The material cannot be completely melted and solidified during the heat exchange process, resulting in uneven distribution of temperature and thermal stress, which further reduces the service life of the phase change material and the material of the heat storage device. Therefore, it is necessary to optimize the structure of the phase change heat storage device.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the defect of the above-mentioned prior art that the uneven distribution of temperature and thermal stress causes the life of the phase change material and the material of the heat storage device to decrease. The defects, and the defects of increasing the heat exchange area of the phase change heat storage device, increase the complexity of the device, increase the manufacturing cost and reduce the filling amount of the phase change material, so a rotary enhanced heat exchange phase change heat storage device is provided.

The object of the present invention can be realized through the following technical solutions:

A rotary enhanced heat exchange phase change heat storage device, comprising a heat storage shell, a rotating device, a phase change heat storage unit and a heat exchange flow channel, the heat storage shell includes a heat storage shell, and the heat storage shell is on the heat storage shell. A heat exchange medium inlet and a heat exchange medium outlet are provided, the rotating device includes a first turntable, a second turntable and a rotating shaft, the phase change heat storage unit includes a heat storage tube and a phase change material assembly, and the heat storage tube includes a heat storage tube The inner tube of the tube, the outer tube of the heat storage tube and the tube wall of the heat storage tube, and the heat exchange flow channel includes a first fluid channel and a second fluid channel.

The heat exchange medium inlet and the heat exchange medium outlet are respectively located at two ends of the heat storage shell, and the heat storage shell adopts a non-detachable structure or a detachable structure, and the detachable structure includes a detachable cover plate and a fastener.

Central positions of both ends of the heat storage shell are respectively provided with fixing holes, and the rotating shafts are arranged in the fixing holes and are respectively connected with the first turntable and the second turntable.

Further, the rotating shaft may be connected to an external power device, or may not be connected to an external power device under the premise of an external power environment, such as an environment such as vibration.

Both the first turntable and the second turntable are provided with a plurality of circular grooves, the circular grooves are arranged in a circular array, and the circular grooves of the first turntable and the second turntable correspond one-to-one.

Further, the centers of the circular grooves of the first turntable and the second turntable are provided with through holes, and the diameter of the through holes is the diameter of the inner cylinder of the heat storage tube.

Further, a plurality of heat storage tubes are arranged on the circular grooves of the first turntable and the second turntable, the heat storage tubes are arranged in a circular array, and the types of the heat storage tubes include round tubes, elliptical tubes, square tubes Tube, straight tube and reducer tube.

The heat storage tube adopts metal or non-metal material.

The phase-change heat storage unit adopts a tubular structure, and the phase-change material component is arranged between the inner tube of the heat storage tube and the outer tube of the heat storage tube.

Further, heat storage tube fins are further provided between the inner tube of the heat storage tube and the outer tube of the heat storage tube, and the types of the heat storage tube fins include annular fins, longitudinal fins and spiral fins.

Further, the material of the phase change material component includes inorganic phase change material, organic phase change material, eutectic phase change material or modified composite phase change material.

A first fluid channel is formed between the outer tube of the heat storage tube and the heat storage shell, and a second fluid channel is formed between the inner tubes of each heat storage tube.

Compared with the prior art, the present invention has the following beneficial effects:

1. The heat exchange efficiency of the present invention is high. On the one hand, in the actual operation of the phase change heat storage device, the phase change heat storage unit can be rotated through the setting of the rotating device, which increases the kinetic energy of the heat exchange medium inside the phase change heat storage device, and the heat exchange medium continuously impacts the heat exchange surface. The convective heat transfer coefficient inside the phase change heat storage device is enhanced. On the other hand, the phase change heat storage unit adopts a casing structure, combined with the first fluid channel and the second fluid channel, to increase the contact area between the heat exchange medium inside the phase change heat storage device and the phase change heat storage unit, and It can effectively slow down the heat accumulation phenomenon and significantly shorten the heat storage and release time of the phase change heat storage unit.

2. The heat exchange uniformity of the present invention is good. Due to the dual functions of the rotary device and the sleeve-type phase change heat storage unit, the heat exchange uniformity of the phase change heat storage device is further improved, which can reduce or even avoid the partial inability of the phase change material to melt and the phase change heat storage device. The phenomenon that the local thermal stress is too high.

3. The flow resistance of the present invention is small, the pressure drop of the phase change heat storage device is small, and the energy consumption to achieve the same heat exchange effect is smaller than that of the traditional phase change heat storage device. Since the present invention does not increase the heat exchange coefficient by increasing the flow rate of the heat exchange medium, the heat exchange medium can enter the fluid channel at a low speed, which will greatly reduce the flow resistance and reduce the power required to transport the heat exchange medium.

4. The device of the present invention is simple, compact in structure, widely used, convenient for manufacture, installation and maintenance, and can flexibly change the structural parameters of the phase change heat storage device according to different application occasions and operating conditions.

Description of drawings

Fig. 1 is the structural representation of the phase change heat storage device of the present invention;

Fig. 2 is the front view of the first embodiment of the phase change heat storage device of the present invention;

Fig. 3 is the A-A sectional view of the first embodiment of the phase change heat storage device of the present invention;

Fig. 4 is the B-B sectional view of the first embodiment of the phase change heat storage device of the present invention;

5 is a schematic diagram of the internal structure of the first embodiment of the phase change heat storage device according to the present invention;

6 is a front view of the internal structure of the first embodiment of the phase change heat storage device of the present invention;

7 is a C-C sectional view of the internal structure of the first embodiment of the phase change heat storage device of the present invention;

8 is a D-D sectional view of the internal structure of the first embodiment of the phase change heat storage device of the present invention;

9 is a schematic structural diagram of a heat storage tube in Embodiment 1 of the phase change heat storage device of the present invention;

FIG. 10 is a front view of a heat storage tube according to Embodiment 1 of the phase change heat storage device of the present invention;

11 is an E-E cross-sectional view of a heat storage tube in Embodiment 1 of the phase change heat storage device of the present invention;

Fig. 12 is the F-F sectional view of the heat storage tube of the first embodiment of the phase change heat storage device of the present invention;

Fig. 13 is the F-F sectional view of the heat storage tube of the third embodiment of the phase change heat storage device of the present invention;

14 is a schematic structural diagram of Embodiment 2 of the phase change heat storage device of the present invention;

15 is a front view of the second embodiment of the phase change heat storage device of the present invention;

16 is a G-G sectional view of the second embodiment of the phase change heat storage device of the present invention;

FIG. 17 is an H-H sectional view of the second embodiment of the phase change heat storage device of the present invention.

Reference number:

1- heat storage shell; 2- heat storage tube inner tube; 3- first turntable; 4- heat storage tube outer tube; 5- heat exchange medium inlet; 6- rotating shaft; 7- second turntable; 8- heat exchange medium outlet; 9-phase change material assembly; 10-first fluid channel; 11-second fluid channel; 12-regenerator tube wall; 13-regenerator fin; 14-removable cover plate; 15-fastener;

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and provides a detailed implementation manner and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

As shown in Figure 1, a rotary enhanced heat exchange phase change heat storage device includes a heat storage shell, a rotating device, a phase change heat storage unit and a heat exchange flow channel, the heat storage shell includes a heat storage shell 1, The heat exchange medium inlet 5 and the heat exchange medium outlet 8 are arranged on the heat shell 1, the rotating device includes a first turntable 3, a second turntable 7 and a rotating shaft 6, and the phase change heat storage unit includes a heat storage tube and a phase change material assembly 9. The heat pipe includes a heat storage tube inner tube 2 , a heat storage tube outer tube 4 and a heat storage tube wall 12 , and the heat exchange flow channel includes a first fluid channel 10 and a second fluid channel 11 .

The heat exchange medium inlet 5 and the heat exchange medium outlet 8 are located at two ends of the heat storage shell 1 respectively. The heat storage shell adopts a non-detachable structure or a detachable structure.

The two ends of the heat storage shell 1 are respectively provided with fixing holes at the center positions, and the rotating shafts 6 are arranged in the fixing holes and are respectively connected with the first turntable 3 and the second turntable 7 .

The rotating shaft 6 may be connected to an external power device, or may not be connected to an external power device under the premise of an external power environment, such as an environment such as vibration.

Both the first turntable 3 and the second turntable 7 are provided with a plurality of circular grooves, and the circular grooves are arranged in a circular array, and the circular grooves of the first turntable 3 and the second turntable 7 correspond one-to-one.

The centers of the circular grooves of the first turntable 3 and the second turntable 7 are provided with through holes, and the diameter of the through holes is the diameter of the inner cylinder 2 of the heat storage tube.

The circular grooves of the first turntable 3 and the second turntable 7 are provided with a plurality of heat storage tubes. The heat storage tubes are arranged in a circular array. The types of heat storage tubes include round tubes, elliptical tubes, square tubes, straight tubes and variable diameters. Tube.

The heat storage tube adopts metal or non-metal material.

The phase change heat storage unit adopts a casing structure, and the phase change material assembly 9 is arranged between the inner tube 2 of the heat storage tube and the outer tube 4 of the heat storage tube.

The heat storage tube fins 13 are further provided between the heat storage tube inner tube 2 and the heat storage tube outer tube 4, and the types of the heat storage tube fins 13 include annular fins, longitudinal fins and spiral fins.

The material of the phase change material component 9 includes inorganic phase change materials, organic phase change materials, eutectic phase change materials or modified composite phase change materials.

A first fluid channel 10 is formed between the outer tube 4 of the heat storage tube and the heat storage shell, and a second fluid channel 11 is formed between the inner tubes 2 of each heat storage tube.

Example 1

This embodiment is a non-removable rotary enhanced heat exchange phase change heat storage device. 1 to 12 are schematic diagrams of Embodiment 1 of the present invention, wherein FIG. 1 is a schematic diagram of the overall structure of Embodiment 1, FIG. 2 is a front view of Embodiment 1, FIG. 3 is A-A cross-sectional view of Embodiment 1, and FIG. 4 is an embodiment B-B sectional view of example one, FIG. 5 is a schematic diagram of the internal structure, FIG. 6 is a front view of the internal structure, FIG. 7 is a C-C cross-sectional view of the internal structure, FIG. 8 is a D-D cross-sectional view of the internal structure, and FIG. 10 is a front view of the heat storage tube, FIG. 11 is an E-E cross-sectional view of the heat storage tube, and FIG. 12 is a F-F cross-sectional view of the heat storage tube.

In the specific implementation, for the heat exchange components, the rotating shaft 6 is first driven by external power, then the first rotating disk 3 and the second rotating disk 7 are driven by the rotating shaft 6, and then the phase change heat storage unit is driven by the first rotating disk 3 and the second rotating disk 7 to carry out Rotational movement. The heat exchange medium first enters the first fluid channel 10 through the heat exchange medium inlet 5 of the heat storage shell. Next, it enters the second fluid channel 11 through the through hole on the first turntable 3, and the flow is distributed to each phase-change heat storage unit. The heat exchange medium entering the second fluid channel 11 then returns to the first fluid channel 10 through the through holes on the second turntable 7 . Finally, the phase change heat storage device flows out through the heat exchange medium outlet 8 of the heat storage shell to complete a heat exchange process. For the phase change heat storage unit, in the process of melting heat storage, the high temperature heat exchange medium exchanges heat with the solid phase change material component 9 in the heat storage tube through the tube wall 12 of the heat storage tube, and the solid phase change material component 9 absorbs enough heat and starts to melt , and eventually all become liquid, completing the entire heat storage process. During the solidification exothermic process, the low-temperature heat exchange medium exchanges heat with the liquid phase change material component 9 in the heat storage tube through the tube wall 12 of the heat storage tube. As the heat exchange proceeds, the temperature of the liquid phase change material component 9 gradually decreases. When the temperature of the liquid phase-change material component 9 is lowered to its phase-change freezing point, its shape will change, and it will change from a liquid state to a solid state to complete the entire exothermic process. This reciprocal melting/solidification cycle can achieve heat storage and release.

Embodiment 2

This embodiment is a detachable rotary enhanced heat exchange phase change heat storage device. 14 to 17 are schematic diagrams of Embodiment 2 of the present invention, wherein, FIG. 14 is a schematic structural diagram of Embodiment 2, FIG. 15 is a front view of Embodiment 2, FIG. 16 is a G-G sectional view of Embodiment 2, and FIG. 17 is a H-H sectional view of Example 2. The specific implementation process of this embodiment is the same as that of the first embodiment, the difference is that the heat storage shell of this embodiment includes a removable cover plate 14, The fastener 15 has a detachable function.

Embodiment 3

This embodiment is a rotary enhanced heat exchange phase change heat storage device with enhanced heat exchange on the phase change material side. FIG. 13 is a F-F sectional view of the third embodiment of the present invention. The specific implementation process of this embodiment is the same as that of the first embodiment, the difference is that the heat storage tube fins 13 are added to the phase change material side in the phase change heat storage unit of this embodiment, so as to achieve the purpose of strengthening heat exchange on the phase change material side. In addition, materials with excellent thermal conductivity, such as metal foam, nanomaterials, expanded graphite, etc., can also be added to the phase change material component 9 .

Embodiment 4

This embodiment is a rotary enhanced heat exchange phase change heat storage device in which the diameter of the heat storage tube is reduced. The specific implementation process of this embodiment is the same as that of the first embodiment, the difference is that the heat storage tube in the phase change heat storage unit of this embodiment is set in the form of variable diameter, which can further improve the heat exchange effect.

Embodiment 5

This embodiment is a microchannel rotary enhanced heat exchange phase change heat storage device. The specific implementation process of this embodiment is the same as that of the specific embodiment 1, the difference is that the second fluid channel 11 of this embodiment is arranged in the form of a micro-channel, which can further improve the heat exchange effect.

In addition, it should be noted that the names of the specific embodiments described in this specification may be different, and the above content described in this specification is only an example to illustrate the structure of the present invention. All equivalent changes or simple changes made according to the structures, features and principles of the present invention are included in the protection scope of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or additions to the specific examples described or adopt similar methods, as long as they do not deviate from the structure of the present invention or go beyond the scope defined by the claims, all It belongs to the protection scope of the present invention.

Claims (10)

1. A rotary enhanced heat exchange phase change heat storage device, characterized in that it comprises a heat storage shell, a rotating device, a phase change heat storage unit and a heat exchange channel, and the heat storage shell comprises a heat storage shell ( 1), the heat storage housing (1) is provided with a heat exchange medium inlet (5) and a heat exchange medium outlet (8), and the rotating device includes a first turntable (3), a second turntable (7) and a rotating shaft (6), the phase change heat storage unit includes a heat storage tube and a phase change material assembly (9), the heat storage tube includes a heat storage tube inner tube (2), a heat storage tube outer tube (4) and a heat storage tube wall (12) ), the heat exchange flow channel includes a first fluid channel (10) and a second fluid channel (11). 2 . The rotary enhanced heat exchange phase change heat storage device according to claim 1 , wherein the heat exchange medium inlet ( 5 ) and the heat exchange medium outlet ( 8 ) are respectively located in the heat storage shell ( 1 ). 3 . ), the heat storage housing adopts a non-detachable structure or a detachable structure, and the detachable structure includes a detachable cover plate (14) and a fastener (15). 3. A rotary enhanced heat exchange phase change heat storage device according to claim 1, characterized in that, fixing holes are respectively provided at the center positions of both ends of the heat storage shell (1), and the rotating shaft (6) ) are arranged in the fixing holes and are respectively connected with the first turntable (3) and the second turntable (7). 4. A rotary enhanced heat exchange phase change heat storage device according to claim 1, characterized in that, the first turntable (3) and the second turntable (7) are both provided with a plurality of circular grooves, so The circular grooves are arranged in a circular array, and the circular grooves of the first turntable (3) and the second turntable (7) are in one-to-one correspondence. 5. A rotary enhanced heat exchange phase change heat storage device according to claim 4, characterized in that, the centers of the circular grooves of the first turntable (3) and the second turntable (7) are provided with through holes, The diameter of the through hole is the diameter of the inner cylinder (2) of the heat storage tube. 6. A rotary enhanced heat exchange phase change heat storage device according to claim 4, characterized in that, a plurality of grooves are provided on the circular grooves of the first turntable (3) and the second turntable (7). Heat storage tubes, the heat storage tubes are arranged in a circular array, and the types of the heat storage tubes include round tubes, elliptical tubes, square tubes, straight tubes and variable diameter tubes. 7. A rotary enhanced heat exchange phase change heat storage device according to claim 1, characterized in that, the phase change heat storage unit adopts a sleeve type structure, and the phase change material assembly (9) is provided in the between the inner tube (2) of the heat storage tube and the outer tube (4) of the heat storage tube. 8. A rotary enhanced heat exchange phase change heat storage device according to claim 7, characterized in that a heat storage tube is also provided between the heat storage tube inner cylinder (2) and the heat storage tube outer tube (4) Fins (13), the types of heat storage tube fins (13) include annular fins, longitudinal fins and helical fins. 9 . The rotary enhanced heat exchange phase change heat storage device according to claim 7 , wherein the material of the phase change material component ( 9 ) comprises inorganic phase change materials, organic phase change materials, Eutectic phase change material or modified composite phase change material. 10. A rotary enhanced heat exchange phase change heat storage device according to claim 1, characterized in that a first fluid channel (10) is formed between the heat storage tube outer cylinder (4) and the heat storage shell , a second fluid channel (11) is formed between each of the inner cylinders (2) of the heat storage tubes.

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