Heat exchange and storage method and system for realizing controllable heat absorption and release time sequence based on periodic mechanical stress triggering plastic crystal non-equilibrium phase

Abstract

The invention belongs to the technical field of phase change heat storage and heat exchange, and particularly relates to a heat exchange and heat storage method and system for realizing controllable heat absorption and release time sequence based on a periodic mechanical stress triggered plastic crystal non-equilibrium phase, a lower cold fluid applies thrust to a baffle when flowing, if the cold fluid and the hot fluid are gas, a pressure difference exists between the upper side and the lower side of a roller, and if the cold fluid and the hot fluid are gas, the pressure difference exists between the upper side and the lower side of the roller; rolling the drum; in the rolling process, the steel balls in the steel ball cylinder reciprocate along the path of the steel ball cylinder under the action of gravity, and when the steel ball cylinder moves to the lower part of the roller, the steel balls impact the inner wall of the roller to induce the plastic crystal material to be converted from an unbalanced phase to an ordered crystal phase, so that heat is released; when the steel ball cylinder moves to the upper part of the roller, the steel balls do not impact the inner wall of the roller, and the material is converted into a plastic crystal phase from a crystal phase again and absorbs heat. The device is simple in overall structure, high in stability and easy to maintain; meanwhile, the heat exchange process is more continuous, large temperature difference between the module and cold and hot fluid can be kept all the time, the heat exchange efficiency is improved, meanwhile, the heat exchanger is suitable for various working conditions, and specific heat exchange fluid states and types are not required.

Description

Technical Field

[0001] This invention relates to the field of phase change thermal energy storage and heat exchange technology, belonging to the field of energy regulation and thermal management application technology of non-equilibrium phase change materials. Specifically, it is a method and system for achieving controllable heat exchange and thermal energy storage based on periodic mechanical stress triggering of crystalline non-equilibrium phases to realize heat absorption and release timing. Background Technology

[0002] As the world's second-largest economy, my country currently accounts for over 20% of global carbon emissions from its industrial sector, making the green and low-carbon transformation of industry an urgent priority. Against this backdrop, waste heat recovery technology, particularly innovative solutions for utilizing waste heat below 200°C, is becoming a core technological path to improve overall energy efficiency and optimize energy costs for businesses. If this wasted heat energy can be effectively recovered, stored, and reused as heat, it can significantly reduce global energy consumption and reduce carbon emissions from heat production at the source. This technology plays a crucial supporting role in achieving the strategic goal of "carbon peaking and carbon neutrality" and has been listed as a key research area for industrial energy conservation transformation.

[0003] Phase change thermal energy storage (PCE) technology is one of the most widely used thermal energy storage technologies. It achieves thermal energy storage and release through material phase transitions. Solid PCEs are considered ideal thermal energy storage carriers due to their advantages such as no liquid phase formation, small volume change, high safety, strong process compatibility, and good cycle stability. However, the heat release of traditional solid PCEs is entirely dependent on ambient temperature changes. Spontaneous phase changes during cooling lead to uncontrollable energy release timing, making it difficult to meet the thermal lag requirements of long-distance transport and the thermal management requirements of wide-temperature-range scenarios. This severely restricts the control precision and utilization efficiency of PCE technology.

[0004] Supercooled plastic crystal and glass crystal materials, with their unique non-equilibrium phase transition characteristics, have opened up innovative technological paths for industrial waste heat recovery. This material system absorbs heat during the transformation from a crystalline phase to a plastic crystal phase upon heating. Most importantly, upon rapid cooling, it maintains the high-temperature plastic crystal structure to a temperature range far below the plastic crystal phase transition point, transforming into a supercooled plastic crystal phase and then a glass crystal phase. The entire phase transition process exhibits significant thermodynamic irreversibility. Unlike traditional phase change materials, these materials with irreversible phase transition characteristics do not undergo spontaneous phase transitions upon temperature decreases, but can be induced to revert to an ordered crystalline phase and release heat through slight pressure. This unique physical mechanism enables cutting-edge applications such as cross-seasonal heat storage, wide-temperature-range thermal regulation, and cross-regional heat transport, providing a novel solution for the long-term storage and spatiotemporal redistribution of industrial waste heat. Therefore, based on the phase transition characteristics of these materials, stress-induced high-temperature heat absorption and low-temperature heat release phase transition methods can be designed and applied to heat exchange systems and waste heat utilization technologies to achieve heat recovery.

[0005] However, current technologies for controlling the non-equilibrium phase transition process of plastic crystals mainly focus on static control of temperature or pressure. There is a lack of a technical means to stably, periodically, and adjustably trigger the non-equilibrium phase transition in engineering systems, particularly making it difficult to achieve precise switching and synchronous control of the heat absorption and release processes over time. This problem is especially prominent in integrated heat exchange and heat storage applications, severely hindering the widespread application of glass plastic crystal materials in practical engineering. Summary of the Invention

[0006] To overcome the problems of uncontrollable heat absorption and release processes and difficulty in engineering-initiated non-equilibrium phase changes in existing phase change thermal energy storage technologies, the present invention aims to provide a heat exchange and storage method and system based on periodic mechanical stress triggering of the non-equilibrium phase of plastic crystal to achieve controllable heat absorption and release timing. By regulating the timing, frequency, and amplitude of mechanical stress, the heat absorption and release processes of glass plastic crystal can be cyclically controlled, thereby improving heat exchange efficiency and the flexibility of thermal energy storage utilization.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] The heat exchange and heat storage method of the present invention includes the following steps:

[0009] Step A: Place the plastic crystal material in a closed space. Under conditions higher than the plastic crystal phase transition temperature of the plastic crystal material, allow the plastic crystal material in the crystalline phase to come into contact with the hot fluid and absorb heat to form a plastic crystal phase. Under conditions lower than the plastic crystal phase transition temperature of the plastic crystal material, keep the plastic crystal material in the non-equilibrium phase.

[0010] Step B involves periodically applying mechanical stress directly or indirectly to the enclosed space where the plastic crystal material is located. When the peak value of the mechanical stress reaches or exceeds a preset induction threshold, the plastic crystal material is triggered to undergo a non-equilibrium phase transition from a non-equilibrium phase to a crystalline phase, and latent heat is released.

[0011] Step C: After the mechanical stress is unloaded or reduced, the plastic crystal material that has undergone phase change is brought into contact with a cold fluid to release heat, or brought into contact with a hot fluid again to absorb heat, thereby realizing a time-controllable periodic cycle of heat absorption and release process.

[0012] Step D involves controlling the timing, frequency, or amplitude of the mechanical stress application to achieve a time-controlled switching between the heat absorption and release processes, thereby completing the heat exchange and storage process.

[0013] Preferably, the non-equilibrium phase includes a supercooled plastic crystal phase or a glassy crystal phase.

[0014] Preferably, the mechanical stress is obtained through the conversion of gravitational potential energy, and the mechanical stress is formed by the periodic movement of a loading body with a set mass within a predetermined height range, generating impact or compression.

[0015] Preferably, the magnitude of the mechanical stress is controlled by adjusting the material and size of the loading body and / or the drop height within a predetermined height range, wherein the drop height is determined by the length of the movement path of the loading body or the structural dimensions forming the predetermined height range; and / or, the peak value of the mechanical stress is 1 to 50 MPa.

[0016] Preferably, the loading frequency of the mechanical stress is matched with the heat exchange conditions to achieve alternating or synchronous control of the heat absorption and heat release phases of the plastic crystal material in time.

[0017] The heat exchange and heat storage system implementing the heat exchange and heat storage method of the present invention includes:

[0018] At least one heat exchange module, wherein the heat exchange module has an enclosed space inside for filling with a plastic crystal material;

[0019] A carrier for installing a heat exchange module, the carrier being provided with a mechanical stress loading mechanism corresponding to the heat exchange module;

[0020] The drive unit is used to drive the carrier to rotate, and the mechanical stress loading mechanism rotates together with the carrier to achieve periodic motion;

[0021] Hot fluid channels and cold fluid channels respectively contact the heat exchange module;

[0022] During its periodic motion, the mechanical stress loading mechanism applies a periodic mechanical stress with controllable peak value to the heat exchange module to trigger a non-equilibrium phase transformation of the plastic crystal material.

[0023] Preferably, the carrier includes a rotatable drum, the heat exchange module is installed on the outer surface of the drum, and the mechanical stress loading mechanism is disposed inside the drum; the mechanical stress loading mechanism includes a loading body, which moves periodically along a predetermined path during the rotation of the drum.

[0024] Preferably, the inner wall of the roller is provided with a container for providing a periodic movement path for the loading body, the length direction of the container is the radial direction of the roller, and the loading body is housed in the container; and / or, the loading body is a spherical or columnar structure.

[0025] Preferably, when the loading body rotates to the lower region of the drum, it directly contacts the heat exchange module and impacts or squeezes it, or indirectly impacts or squeezes the heat exchange module by impacting or squeezing the inner wall of the drum, thereby generating mechanical stress in the heat exchange module to induce phase change of the plastic crystal material.

[0026] Preferably, the carrier is provided with baffles for interacting with hot or cold fluids, and the rotational speed of the carrier is adjusted by the number, size, or arrangement of the baffles, thereby adjusting the loading frequency of the mechanical stress.

[0027] The advantages and positive effects of this invention are as follows:

[0028] 1. This invention applies mechanical stress to the supercooled phase and glass crystal phase of the plastic crystal material by steel balls inside the drum under the action of gravity, thereby triggering its exothermic phase transformation process. It does not require additional complex driving devices or high-energy-consuming actuators, has a simple structure, high reliability, and is suitable for long-term stable operation.

[0029] 2. This invention utilizes the self-flow of cold fluid to apply thrust to the baffle, driving the drum to rotate periodically, so that the plastic crystal material installed in the heat exchange module on the drum completes the cyclic process of absorbing heat from a high position to releasing heat from a low position within the same device; compared with the existing schemes that require transferring materials to different positions or different devices for heat absorption and release, this invention realizes the in-situ recycling of materials, significantly simplifying the system structure.

[0030] 3. This invention, through the continuous rotation of the drum and the periodic absorption and release of heat by the material, can achieve the orderly superposition of intermittent heat absorption and release under the condition of continuous flow of cold and hot fluids, making the overall heat exchange process of the system approximately continuous, thereby improving heat exchange efficiency and reducing fluid switching and control complexity. At the same time, this invention eliminates the need for close or direct contact between cold and hot fluids and does not require a specific conveying method. Therefore, this invention is applicable to heat exchange between different types and states of heat exchange fluids, and may provide assistance for the layout and optimization of production routes in actual production.

[0031] 4. This invention adopts a modular heat exchange unit design, where each module can operate and be replaced independently. Compared to traditional shell-and-tube heat exchangers, the heat exchange process takes place outside the module or in a semi-open structure, making it less prone to blockage or serious damage. Even if a partial module fails, it will not have a significant impact on the overall system operation, making maintenance and expansion more convenient. At the same time, any parameters (such as the mass of the steel balls, the number and distribution of heat exchange modules, and the size of the steel ball cylinder) can be predicted by calculation before formal production and can be adjusted at any time before production without the need for complete replacement.

[0032] 5. Some of the glass plastic crystal materials of this invention can remain stable at room temperature after endothermic phase change and retain their heat release capacity for a long time; combined with modular and drum circulation structure, this invention can separate heat from the original production process and release it at different times or in different application scenarios, improving the flexibility and applicability of industrial waste heat recovery and utilization. Attached Figure Description

[0033] Figure 1 This is a three-dimensional structural diagram of the heat exchange and heat storage system of the present invention;

[0034] Figure 2 for Figure 1 Radial cross-sectional view of the drum, baffle and steel ball cylinder in the heat exchange and storage system;

[0035] Figure 3 for Figure 2 A schematic diagram showing the position of the steel ball inside the steel ball cylinder at different times during reciprocating motion;

[0036] Figure 4 for Figure 1 A three-dimensional structural diagram of the heat exchange module;

[0037] Figure 5 for Figure 1 Cross-sectional view along the thickness direction of the heat exchange module;

[0038] Figure 6 for Figure 1 Workflow diagram of heat exchange and heat storage system;

[0039] Wherein: 1 is the upper plate, 2 is the middle plate, 3 is the lower plate, 4 is screw A, 5 is the sealing ring, 6 is the cavity, 7 is the heat exchange module, 8 is the baffle, 9 is the T-groove, 10 is the roller, 11 is the steel pipe, 12 is the end cap, 13 is screw B, 14 is the steel ball cylinder, and 15 is the steel ball. Detailed Implementation

[0040] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0041] This invention relates to a method for heat transfer and storage with controllable heat absorption and release sequence based on periodic mechanical stress-triggered plastic crystal non-equilibrium phase, comprising the following steps:

[0042] Step A: Place the plastic crystal material in a closed space. Under conditions higher than the plastic crystal phase transition temperature of the plastic crystal material, allow the plastic crystal material in the crystalline phase to come into contact with the hot fluid and absorb heat to form a plastic crystal phase. Under conditions lower than the plastic crystal phase transition temperature of the plastic crystal material, keep the plastic crystal material in a non-equilibrium phase, including a supercooled plastic crystal phase or a glassy crystalline phase.

[0043] Step B involves periodically applying mechanical stress directly or indirectly to the enclosed space where the plastic crystal material is located. When the peak value of the mechanical stress reaches or exceeds the preset induction threshold, it triggers a non-equilibrium phase transition from the non-equilibrium phase to the crystalline phase in the plastic crystal material and releases latent heat.

[0044] Step C: After the mechanical stress is unloaded or reduced, the plastic crystal material that has undergone phase change is brought into contact with a cold fluid to release heat, or brought into contact with a hot fluid again to absorb heat, thereby realizing a time-controllable periodic cycle of heat absorption and release process.

[0045] Step D involves controlling the timing, frequency, or amplitude of mechanical stress application to achieve time-controlled switching between heat absorption and heat release processes, thereby completing the heat exchange and heat storage process.

[0046] The mechanical stress of this invention is obtained through the conversion of gravitational potential energy. The mechanical stress is formed by the periodic movement of a loading body with a set mass within a predetermined height range, generating impact or compression. The magnitude of the mechanical stress is controlled by adjusting the material and size of the loading body and / or the drop height within the predetermined height range. The drop height is determined by the length of the loading body's movement path or the structural dimensions forming the predetermined height range. The peak value of the mechanical stress is 1–50 MPa, preferably 10 MPa, to ensure stable induction of a non-equilibrium phase transition from supercooled plastic crystals or glass crystals to an ordered crystalline phase. The loading frequency of the mechanical stress is matched with the heat exchange conditions to achieve alternating or synchronous control of the endothermic and exothermic phases of the plastic crystal material in time.

[0047] The heat exchange and heat storage system of the present invention includes:

[0048] At least one heat exchange module, the heat exchange module having an enclosed space inside for filling with a plastic crystal material;

[0049] A carrier for installing heat exchange modules, the carrier is equipped with a mechanical stress loading mechanism corresponding to the heat exchange modules;

[0050] The drive unit used to drive the carrier to rotate, and the mechanical stress loading mechanism rotate together with the carrier to achieve periodic motion;

[0051] Hot fluid channels and cold fluid channels that respectively contact the heat exchange module;

[0052] Among them, the mechanical stress loading mechanism applies a periodic mechanical stress with controllable peak value to the heat exchange module during the periodic movement to trigger the non-equilibrium phase transformation of the plastic crystal material.

[0053] The carrier includes a rotatable drum, a heat exchange module is installed on the outer surface of the drum, and a mechanical stress loading mechanism is set inside the drum; the mechanical stress loading mechanism includes a loading body, which moves periodically along a predetermined path during the rotation of the drum.

[0054] The inner wall of the drum is provided with a container for providing a periodic movement path for the loading body. The length direction of the container is the radial direction of the drum, and the loading body is housed in the container. The loading body is a spherical or cylindrical structure.

[0055] When the loading body rotates to the lower region of the drum, it directly impacts or compresses the heat exchange module, or indirectly impacts or compresses the heat exchange module by impacting or compressing the inner wall of the drum. This generates mechanical stress within the heat exchange module to induce phase change in the plastic crystal material. The mass of the loading body, the length of its movement path, the size of the carrier, and the number and distribution of the heat exchange modules are designed according to the specific heat exchange or heat storage conditions to achieve matching control of the mechanical stress amplitude and the heat absorption and release sequence.

[0056] The carrier is equipped with baffles for interacting with hot or cold fluids. The rotational speed of the carrier is adjusted by the number, size, or arrangement of the baffles, thereby adjusting the loading frequency of mechanical stress.

[0057] like Figure 4 , Figure 5 As shown, the heat exchange module of this embodiment includes an upper plate 1, a middle plate 2, and a lower plate 3. The upper plate 1 and the lower plate 3 are both square plates. The middle plate 2 is a hollow square frame with open top and bottom, and has a cavity 6 inside. The cavity 6 is used to fill the plastic crystal material. The edges of the upper plate 1, the middle plate 2, and the lower plate 3 are respectively provided with multiple screw holes 16, and each screw A4 is provided in the screw hole 16. Sealing rings 5 ​​are provided between the upper plate 1 and the middle plate 2 and between the middle plate 2 and the lower plate 3. The upper plate 1, the middle plate 2, and the lower plate 3 are sealed and fixedly connected by the screws A4 and the sealing rings 5, so that the cavity 6 becomes a closed space for filling the plastic crystal material and prevents external fluid from seeping in.

[0058] In this embodiment, the upper plate 1 is made of a material with good toughness and poor thermal conductivity, such as composite fiber, metal ceramic, or a metal plate with an asbestos interlayer. The metal plate can be made of a metal material with high strength and impact resistance, including but not limited to stainless steel, aluminum alloy, titanium alloy, nickel-based alloy, or copper alloy. The upper plate 1 can reduce the loss caused by the impact of the steel ball 15 during use and, to a certain extent, determine the heat release direction of the plastic crystal material (it does not release heat towards the upper plate 1). During installation, the upper plate 1 of the heat exchange module faces the inside of the drum 10, while the lower plate 3 faces the fluid. The heat exchange module is installed from the position of the drum 10 closer to the ground, with the upper plate 1 facing the inside of the drum 10. The distinction between the upper and lower layers of the heat exchange module is based on this.

[0059] In this embodiment, the lower plate 3 is made of a material with good thermal conductivity, such as copper or aluminum.

[0060] This embodiment does not have specific requirements for the material of the middle layer plate 2.

[0061] The thickness of the upper plate 1 and the lower plate 3 should not be too thick, otherwise it will affect heat transfer and transmission. However, the specific thickness should be based on the actual working conditions. In this embodiment, the thickness of the upper plate 1 is 0.5-5mm, preferably 1-3mm, to balance impact resistance and thermal insulation. In this embodiment, the thickness of the lower plate 3 is 0.5-5mm, preferably 1-2mm, to improve the heat exchange efficiency with the fluid.

[0062] In this embodiment, after filling the cavity 6 with crystalline material, a vacuum is evacuated from the cavity 6 inside the middle layer plate 2. Vacuum evacuation can be achieved by additionally designing a valve on the upper layer plate 1 or the lower layer plate 3, with the valve connected to the cavity 6 via a pipe. Alternatively, a simpler method can be used: after external sealing, vacuum is evacuated through the screw holes 16 corresponding to one or more screws A4. Simply clamp the rubber tube used for vacuum evacuation with wire or clamps after evacuation, and then cut the rubber tube. Most crystalline materials have a low oxidation rate in room temperature air; avoiding complete contact with air is sufficient to ensure the normal operation of the heat exchange module. Simultaneously, an aluminum-containing paint is sprayed onto the outer surface of the heat exchange module, especially the gaps between the layers, to form a paint coating to prevent oxidation of the internal crystalline material. In any other form of heat exchange and storage system using a modular structure containing crystalline material, the principle of "preventing oxidation of the crystalline material" should be prioritized, and proper sealing of the materials is essential.

[0063] like Figures 1-3 As shown, the carrier in this embodiment is a roller 10, which is a hollow cylinder. End caps 12 are fixed to both ends of the roller 10 via screws B13. Steel pipes 11 are fixed to the middle of the end caps 12 at both ends, and the steel pipes 11 can be rotatably mounted on the foundation via bearings. Multiple T-shaped grooves 9 are evenly distributed axially on the outer circumferential surface of the roller 10, each T-shaped groove 9 penetrating the outer circumferential surface of the roller 10. Multiple baffles 8 are evenly installed circumferentially on the roller 10. The root of each baffle 8 is a T-shape corresponding to the shape of the T-shaped groove 9. The root of each baffle 8 is inserted into and fixed in one T-shaped groove 9. The number of baffles 8 is less than or equal to the number of T-shaped grooves 9, and the rotational speed can be adjusted by adjusting the number of inserted baffles 8.

[0064] The distribution, quantity, and size of the heat exchange modules 7 on the drum 10 should be based on actual working conditions. When the temperature difference between fluids and the required heat exchange are large, more heat exchange modules 7 should be used, and their distribution should be more dense. At the same time, the drum 10 may not be fully loaded with heat exchange modules 7 when put into use. In this embodiment, a row of heat exchange modules 7 installed along the axial direction of the drum 10 is provided between two adjacent T-shaped grooves 9, with the upper plate 1 of the heat exchange modules 7 facing the interior of the drum 10. The heat exchange modules 7 can be installed on the outer surface of the drum 10 without communicating with the interior of the drum 10, or mounting holes for installing the heat exchange modules 7 can be opened on the outer surface of the drum 10, with each mounting hole communicating with the interior of the drum 10.

[0065] In this embodiment, the container installed on the inner wall of the drum 10 to provide a periodic movement path for the loading body is a steel ball cylinder 14. The number of steel ball cylinders 14 is the same as the number of heat exchange modules 7, and they correspond one-to-one. Each steel ball cylinder 14 is a cylinder with one open end, and the open end of the steel ball cylinder 14 is fixed to the inner wall of the drum 10. The axial center line of each steel ball 15 intersects the axial center line of the drum 10 perpendicularly. When mounting holes are opened on the outer surface of the drum 10, the size of the mounting holes is larger than the size of the open end of the steel ball cylinder 14.

[0066] In this embodiment, the loading body is a steel ball 15, and each steel ball cylinder 14 contains one steel ball 15. The diameter of the steel ball 15 in this embodiment is smaller than the diameter of the bottom surface (i.e., the closed end) of the steel ball cylinder 14. The steel ball 15 is made of a material with high hardness, such as tungsten cobalt alloy, titanium nickel alloy, or high manganese steel. If necessary, oil can be applied to the inner wall of the steel ball cylinder 14 to reduce friction. On this basis, the larger the mass of the steel ball 15 and the longer the steel ball cylinder 14, the stronger the impact on the inner wall of the roller 10, and the easier it is to induce the phase change and exothermic reaction of the plastic crystal material.

[0067] In this embodiment, the cold fluid channel is located below the drum 10. The top of the portion of the cold fluid channel directly below the drum 10 is an open structure. The baffle 8 at the bottom of the drum 10 can extend into the cold fluid channel from the open portion, and the heat exchange module 7 at the bottom of the drum 10 can contact and exchange heat with the cold fluid in the cold fluid channel. The drive unit in this embodiment can be considered as the cold fluid. When the cold fluid flows in the cold fluid channel, it exerts force on the baffle 8, driving the drum 10 to rotate around the steel pipe 11. The cold fluid in this embodiment can be a liquid or gaseous cooling medium, including but not limited to water, cooling water, aqueous solution, antifreeze, oil-based cooling medium, air, nitrogen, or other inert gases; its temperature range can be -40℃ to 40℃, preferably -10℃ to 30℃.

[0068] In this embodiment, the hot fluid channel is located above the roller 10. The hot fluid channel is a flexible channel made of a soft membrane. The soft membrane comprises a polymer matrix and a high thermal conductivity filler. The matrix is ​​an elastomer or thermoplastic elastomer, and the filler is a sheet-like / fibrous / granular high thermal conductivity filler. The filler is oriented within the membrane surface to improve in-plane and thickness-direction thermal conductivity. The matrix can be one of silicone rubber, fluororubber, TPU, TPE, or PI (polyimide), and the filler can be one of boron nitride (BN), aluminum nitride (AlN), carbon fiber, graphite / graphene, or carbon nanotubes. The filler content can be 5–70 wt% (preferably 20–50 wt%). A hot fluid flows inside the hot fluid channel. In this embodiment, the hot fluid can be a liquid or gaseous heat transfer medium, including but not limited to water, steam, heat transfer oil, industrial waste heat gas, air, or inert gas. Its temperature range can be 40℃–200℃, preferably 60℃–150℃. The hot fluid channel is placed on the drum 10 and can adapt to the shape of the drum 10, the baffle 8, and the heat exchange module 7. This ensures that the baffle 8 rotates with the drum 10 and can contact the heat exchange module 7 that has rotated to the top. In this embodiment, the baffle 8 is made of metal or a high thermal conductivity composite material, preferably aluminum alloy, copper alloy, stainless steel, titanium alloy, or thermally conductive ceramic / thermally conductive composite material. The surface of the baffle 8 can be provided with a low-friction wear-resistant coating or overlay to reduce friction and wear with the soft film and maintain thermally conductive contact. The edges of the baffle 8 are rounded or chamfered to reduce stress concentration and wear on the soft film.

[0069] During the rolling process of the roller 10 in this embodiment, the steel balls 15 inside the steel ball cylinder 14 reciprocate along the path inside the steel ball cylinder 14 under the action of gravity. Figure 5 This also reflects the position of the steel ball 15 within the steel ball cylinder 14 at different times during its reciprocating motion. When the steel ball cylinder 14 moves to the lower part of the drum 10, the steel ball 15 impacts the inner wall of the drum 10, and then indirectly impacts the heat exchange module 7 through the inner wall, inducing a phase change and heat release in the plastic crystal material within the heat exchange module 7. When the steel ball cylinder 14 moves to the upper part of the drum 10, the steel ball 15 does not impact the inner wall of the drum 10, and the phase change material absorbs heat. If the heat exchange module 7 is installed in a mounting hole on the outer surface of the drum 10, the steel ball cylinder 14 directly impacts the heat exchange module 7, inducing a phase change and heat release in the plastic crystal material within the heat exchange module 7.

[0070] The rotation of the drum 10 can be generated either by the cold fluid applying a thrust to the baffle 8 or by an external drive unit. The rotation of the drum 10 causes the crystalline material within the heat exchange module 7 to circulate repeatedly, achieving heat absorption through contact with the hot fluid at the higher position and heat release through a non-equilibrium phase change triggered by gravity at the lower position, thus continuously completing the heat absorption and release cycle. During this cycle, the crystalline material remains enclosed within the heat exchange module 7 and can be reused. Specifically, as follows... Figure 6As shown, in the heat exchange and storage system of this embodiment, the heat exchange module 7 at the top of the drum 10 contacts the hot fluid, while the heat exchange module 7 at the bottom of the drum 10 contacts the cold fluid. The hot fluid must be located above the drum 10 because the steel balls 15 in the ball cylinder 14 at the bottom of the drum 10 are impacted by gravity against the inner wall of the drum 10, causing the plastic crystal material in the heat exchange module 7 at the bottom of the drum 10 to release heat. However, the steel balls 15 in the ball cylinder 14 at the top of the drum 10 are impacted by gravity at the closed end of the ball cylinder 14, preventing the plastic crystal material in the heat exchange module 7 at the top of the drum 10 from being impacted by the steel balls 15 and thus preventing heat release. In this embodiment, the cold fluid is used to apply force to the baffle 8. It should be noted that the heat exchange module 7 at the bottom of the drum 10 first exchanges heat with the cold fluid using the temperature difference (this can be called the first stage heat exchange process). Then, the heat in the plastic crystal material is released by the impact of the steel balls 15 in the steel ball cylinder 14 at the bottom of the drum 10 (this can be called the second stage heat exchange process). When the inlet temperature of the hot fluid exceeds 80°C, the plastic crystal material may partially melt for some plastic crystal material systems. Since the heat exchange module 7 has sealing measures, there is no need to consider leakage issues. However, the number, size and distribution of the heat exchange modules 7 should be designed to ensure that when the heat exchange module 7 comes into contact with the cold fluid, the plastic crystal material in the heat exchange module 7 can quickly change from the plastic crystal phase or even the liquid phase to the supercooled plastic crystal phase, thus making the second stage heat exchange process possible. The greater the temperature difference between the cold and hot fluids, the easier the process is to achieve. This is because the real-time temperature of the heat exchange module 7 is directly related to the temperatures of the cold and hot fluids it comes into contact with. The higher the temperature of the hot fluid, the higher the temperature of the heat exchange module 7 in contact with it. When these heat exchange modules 7 come into contact with the cold fluid, the higher the heat exchange rate, and the easier it is to rapidly transform from the crystalline or liquid phase to the supercooled crystalline phase. When the temperature of the hot fluid does not exceed 80°C, most crystalline materials will not melt.

[0071] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for heat transfer and storage with controllable heat absorption and release sequence based on periodic mechanical stress-triggered crystalline non-equilibrium phase, characterized in that: Includes the following steps Step A: Place the plastic crystal material in a closed space. Under conditions higher than the plastic crystal phase transition temperature of the plastic crystal material, allow the plastic crystal material in the crystalline phase to come into contact with the hot fluid and absorb heat to form a plastic crystal phase. Under conditions lower than the plastic crystal phase transition temperature of the plastic crystal material, keep the plastic crystal material in the non-equilibrium phase. Step B involves periodically applying mechanical stress directly or indirectly to the enclosed space where the plastic crystal material is located. When the peak value of the mechanical stress reaches or exceeds a preset induction threshold, the plastic crystal material is triggered to undergo a non-equilibrium phase transition from a non-equilibrium phase to a crystalline phase, and latent heat is released. Step C: After the mechanical stress is unloaded or reduced, the plastic crystal material that has undergone phase change is brought into contact with a cold fluid to release heat, or brought into contact with a hot fluid again to absorb heat, thereby realizing a time-controllable periodic cycle of heat absorption and release process. Step D involves controlling the timing, frequency, or amplitude of the mechanical stress application to achieve a time-controlled switching between the heat absorption and release processes, thereby completing the heat exchange and storage process.

2. The method according to claim 1, characterized in that: The non-equilibrium phase includes a supercooled plastic crystal phase or a glassy crystal phase.

3. The method according to claim 1, characterized in that: The mechanical stress is obtained through the conversion of gravitational potential energy. The mechanical stress is formed by the periodic movement of a loading body with a set mass within a predetermined height range, generating impact or compression.

4. The method according to claim 3, characterized in that: The magnitude of the mechanical stress is controlled by adjusting the material and size of the loading body and / or the drop height within a predetermined height range, wherein the drop height is determined by the length of the movement path of the loading body or the structural dimensions forming the predetermined height range; and / or, the peak value of the mechanical stress is 1 to 50 MPa.

5. The method according to claim 1, characterized in that: The loading frequency of the mechanical stress is matched with the heat exchange conditions to achieve the alternating or synchronous control of the heat absorption and heat release phases of the plastic crystal material in time.

6. A heat exchange and heat storage system implementing the method of any one of claims 1 to 5, characterized in that: include At least one heat exchange module, wherein the heat exchange module has an enclosed space inside for filling with a plastic crystal material; A carrier for installing a heat exchange module, the carrier being provided with a mechanical stress loading mechanism corresponding to the heat exchange module; The drive unit is used to drive the carrier to rotate, and the mechanical stress loading mechanism rotates together with the carrier to achieve periodic motion; Hot fluid channels and cold fluid channels respectively contact the heat exchange module; During its periodic motion, the mechanical stress loading mechanism applies a periodic mechanical stress with controllable peak value to the heat exchange module to trigger a non-equilibrium phase transformation of the plastic crystal material.

7. The heat exchange and heat storage system according to claim 6, characterized in that: The carrier includes a rotatable drum, the heat exchange module is installed on the outer surface of the drum, and the mechanical stress loading mechanism is disposed inside the drum; the mechanical stress loading mechanism includes a loading body, which moves periodically along a predetermined path during the rotation of the drum.

8. The heat exchange and heat storage system according to claim 7, characterized in that: The inner wall of the roller is provided with a container for providing a periodic movement path for the loading body, the length direction of the container is the radial direction of the roller, and the loading body is housed in the container; and / or, the loading body is a spherical or columnar structure.

9. The heat exchange and heat storage system according to claim 6, characterized in that: When the loading body rotates to the lower region of the drum, it directly contacts the heat exchange module and impacts or squeezes it, or indirectly impacts or squeezes the heat exchange module by impacting or squeezing the inner wall of the drum, thereby generating mechanical stress in the heat exchange module to induce phase change of the plastic crystal material.

10. The heat exchange and heat storage system according to claim 6, characterized in that: The carrier is provided with baffles for interacting with hot or cold fluids. The rotational speed of the carrier is adjusted by the number, size, or arrangement of the baffles, thereby adjusting the loading frequency of the mechanical stress.

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