Intelligent temperature control system and cold start optimization method based on gradient porous solid waste-based composite heat storage material

Abstract

The application belongs to the technical field of energy storage and energy saving, and particularly relates to an intelligent temperature control system and a cold start optimization method based on gradient porous solid waste-based composite heat storage materials. In the system, a high-thermal-conductivity metal heat exchanger with Fibonacci tree-shaped fins is built in a heat storage-heat exchange core unit, and gradient porous solid waste-based heat storage materials are filled to form a heat transfer enhancement structure; a hydraulic circulation unit is connected with a water storage tank, a water pump and a user radiator; a steam unit adjusts the state of the heat storage materials by spraying steam; and an intelligent temperature control unit realizes precise temperature control by linking sensors and controllers with each component. The system can be integrated with an auxiliary combustion unit, the porosity of the heat storage materials decreases from the surface to the inside, and the heat transfer efficiency and energy utilization are optimized. The industrial solid waste-based gradient porous composite heat storage materials, combined with the tree-shaped fin heat transfer enhancement and intelligent start control, realize high heat storage density, fast response and precise temperature control, and provide an efficient and green heat storage solution for the building and industrial fields.

Description

Technical Field

[0001] This invention belongs to the field of energy storage and energy conservation technology, specifically relating to an intelligent temperature control system and cold start optimization method based on gradient porous solid waste-based composite thermal storage material. Background Technology

[0002] In existing technologies, the cold start performance and dynamic thermal energy regulation capabilities of thermal storage systems remain key issues that urgently need improvement. For example, the latent heat system of composite nanoparticles based on Fibonacci fractal tree fins disclosed in patent CN119720517A, although enhancing heat transfer through fractal fins and nanoparticles, still falls short in terms of thermal response speed and initial thermal energy utilization during the cold start phase. The battery-inspired heat dissipation and heat recovery system disclosed in patent CN111129662A, while capable of recovering waste heat, has limitations in handling complex operating conditions, particularly in rapid temperature rise and intelligent regulation during cold starts. None of the above technologies fully address the issues of rapid response, efficient energy conversion, and precise dynamic regulation of thermal storage materials during the cold start phase, especially in the area of ​​utilizing auxiliary heat sources (such as steam or gas) for rapid start-up, where a technological gap exists. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention proposes an intelligent temperature control system and cold start optimization method based on gradient porous solid waste-based composite thermal storage materials. This invention aims to achieve rapid cold start, efficient energy conversion, and precise temperature control of the system through the synergistic effect of gradient porous solid waste-based composite material design, tree-fin-porous layer coupling to enhance heat transfer structure, and intelligent temperature control and cold start optimization strategies, thereby significantly improving the overall performance and economy of the thermal storage system.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: In the first aspect, an intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material is provided, including: a thermal storage-heat exchange core unit, a hydraulic circulation unit, a steam generation and injection unit, and an intelligent temperature control unit.

[0005] The heat storage-heat exchange core unit includes an external metal heat exchanger and a gradient porous solid waste-based composite heat storage material filled inside it; the external metal heat exchanger is made of a high thermal conductivity copper alloy, and its inner wall is provided with an integrally formed Fibonacci tree-shaped fin; the gradient porous solid waste-based composite heat storage material is tightly embedded between the tree-shaped fins and the internal cavity to form a tree-shaped fin-porous layer coupled and enhanced heat transfer structure; the outer side of the external metal heat exchanger tube is wrapped with a glass fiber vacuum insulation layer (4).

[0006] The hydraulic circulation unit includes a water storage tank, a water pump, the heat storage-heat exchange core unit, an outlet valve, and several branch pipes connected to the rear end of the outlet valve and the user-side radiator, all connected in sequence via pipes.

[0007] The steam generation and injection unit includes a steam generator, a steam pipeline, a steam control valve, and a nozzle; the steam generated by the steam generator is transported through the steam pipeline and injected into the inlet or internal space of the heat storage-heat exchange core unit through the nozzle.

[0008] The intelligent temperature control unit includes a temperature sensor group, a flow sensor, and a controller; the temperature sensor group is arranged at key points inside the heat storage material and at the inlet and outlet of the heat exchange pipe; the flow sensor is installed in the hydraulic circulation unit pipe and the steam pipe; the controller is electrically connected to the temperature sensor group, the flow sensor, the water pump, the outlet valve, the steam control valve, and the nozzle respectively.

[0009] Preferably, the system further includes an auxiliary combustion unit, comprising a burner, a gas supply pipeline and gas valve connected to an external gas source, and a combustion-supporting fan and fan valve for providing combustion air to the burner. The controller is also connected to the gas valve and the fan valve. The steam generator can be integrated around the auxiliary combustion unit to utilize the heat generated by the combustion in the auxiliary combustion unit.

[0010] Preferably, the gradient porous structure contained in the gradient porous material exhibits a porosity distribution that gradually decreases from the surface to the interior along the thickness direction. Specifically, the surface layer is a high-porosity region with a porosity >70%, which is conducive to rapid heat exchange with the air or steam side; the middle layer is a medium-porosity region with a porosity of 50%-70%, serving as a transition layer; and the inner layer is a low-porosity region with a porosity <50%, which is conducive to efficient heat transfer with the heat exchange tube wall and the water side.

[0011] A further preferred gradient porous structure has the following porosity distribution: 80% porosity in the surface layer, 65% porosity in the middle layer, and 50% porosity in the inner layer.

[0012] The preparation method of the gradient porous solid waste-based composite thermal storage material includes the following steps: Step 1: Vibration molding: Industrial solid waste powder (such as fly ash, metallurgical slag, particle size 1μm~100μm) is mixed with binder (such as polyvinyl alcohol aqueous solution) and pore-forming agent (such as ammonium bicarbonate) in a certain proportion; it is vibrated at a specific frequency (such as 50Hz) and amplitude to press into a preform with a preset porosity gradient; Step 2: Sintering: Place the preform in a sintering furnace and heat it to 800-1100°C at a rate of 5-10°C / min under a protective atmosphere (such as nitrogen or argon). Hold it at this temperature for 1-3 hours to form a metallurgical bond between the powder particles. Step 3: Burning and infiltration: Under air atmosphere, the temperature is raised to 400-600℃ at a heating rate of 1-5℃ / min and held for 1-2 hours to allow the organic binder and pore-forming agent added in Step 1 to fully decompose and be discharged, forming a rigid matrix with a gradient porous structure. Step 4: Vacuum impregnation: The uniform slurry composed of molten sodium nitrate-potassium nitrate eutectic salt phase change material and nano-reinforcing particles (such as graphene and silicon carbide) is impregnated into a gradient porous matrix under vacuum conditions. Step 5: Post-treatment: Dry the impregnated composite material at 60~80℃ for 2~4 hours, and then heat treat it at 120~150℃ for 0.5~1 hours to finally obtain a gradient porous solid waste-based composite thermal storage material.

[0013] Preferably, the key performance indicators of the material are as follows: high-temperature heat storage density ρ = 0.8~1.0 J / (kg·K), phase change melting temperature T = 150~200℃, thermal conductivity λ = 1.3~1.5 W / (m·K), and volume expansion coefficient α ≈ 1.5×10⁻⁶. -5 / K.

[0014] Secondly, a cold start optimization method using the above system is provided, including the following steps: S1. System self-test and preheating: The system starts up and the controller performs equipment self-test; the water pump is started to pump water from the water tank into the heat storage-heat exchange core unit to preheat the internal heat storage materials and pipes. S2. Steam-assisted rapid heating (underwater ignition): When the initial temperature of the heat storage material is detected to be low, the controller starts the steam generation and injection unit; the nozzle injects a certain flow rate (e.g., 1~2 kg / s) of superheated steam into the heat storage unit. The steam condenses and releases heat in the porous structure of the material, realizing rapid and uniform "underwater ignition" heating and avoiding local overheating. S3, Intelligent Temperature Judgment and Fuel Switching: Temperature sensors monitor the temperature of the thermal storage material and the outlet water in real time; when the temperature reaches the preset primary threshold (such as sufficient to maintain phase change or meet basic heating needs), the controller can adjust the steam injection volume or close the steam valve; if it is necessary to further increase the temperature or the steam heat source is insufficient, the auxiliary combustion unit will be started. S4. Pneumatic high-pulse ignition (if combustion unit is activated): The controller executes the step-by-step ignition procedure sequentially: a) First, a small amount of atomized steam is injected into the burner area to preheat the combustion chamber and establish a stable ignition environment; b) Then, the gas valve is opened to inject gas, which is ignited by the electric igniter or the stabilized high-temperature environment to form a stable flame; c) After combustion stabilizes, the steam injection is stopped; this process ensures reliable ignition and prevents flameout in cold conditions through steam pilot control. S5. System steady-state operation: When the outlet water temperature reaches the set working temperature, the controller closes the heating valve (gas / steam) and opens the outlet valve to distribute hot water to the radiators on each user side as needed, and the system enters a stable heating state. S6. System Shutdown and Safety Protection: After the user stops using heat or the target is reached, the controller sequentially closes the gas valve, fan valve, water pump, etc., to ensure the safe shutdown of the system.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: Materials and Environmental Innovation: Using industrial solid waste as the main raw material, it is low-cost and environmentally friendly; through gradient pore design and composite with nano phase change materials, it achieves a balance between high heat storage density and high thermal conductivity.

[0016] Structural innovation: The tree-shaped fin-porous layer coupling structure significantly increases the effective heat transfer area, induces turbulence, and greatly enhances the heat transfer performance between the phase change material and the heat transfer fluid.

[0017] Control and Start-up Innovation: The system integrates intelligent temperature control with a multi-source (steam, gas) complementary cold start strategy, enabling rapid system response (significantly shortened cold start time), precise temperature control (±3℃), and stable and efficient operation under complex working conditions.

[0018] System integration innovation: It organically integrates solid waste resource utilization, high-efficiency thermal storage, intelligent control and cold start optimization technology, and provides a complete high-efficiency thermal storage and temperature control solution suitable for building energy conservation and industrial waste heat recovery. Attached Figure Description

[0019] Figure 1 This is an integrated schematic diagram of the intelligent temperature control system of the present invention.

[0020] Figure 2 This is a schematic diagram of the structure of a gradient porous solid waste-based thermal storage material.

[0021] Figure 3 This is a flowchart of the cold start process for the intelligent temperature control system.

[0022] In the diagram: 1. Thermal storage-heat exchange core unit; 2. Gradient porous solid waste-based composite thermal storage material; 3. Tree-shaped fins; 4. Glass fiber vacuum insulation layer; 5. Water tank; 6. Water pump; 7. Radiator; 8. Controller; 9. Temperature sensor; 10. Nozzle; 11. Burner; 12. Gas valve; 13. Combustion fan; 14. Water outlet valve; 15. Steam generator; 16. Steam control valve; 17. Solid waste matrix skeleton; 18. Phase change material; 19. Heat flow path; 20. Surface high-porosity zone; 21. Middle layer medium-porosity zone; 22. Inner layer low-porosity zone. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are for illustrative purposes only and do not constitute a limitation on the scope of protection of this invention.

[0024] Example 1: Basic System Structure and Material Preparation This embodiment demonstrates the basic structure of the system of the present invention and a specific preparation method of the gradient porous solid waste-based composite thermal storage material.

[0025] The system is as follows Figure 1 As shown, it includes a heat storage-heat exchange core unit 1, a hydraulic circulation unit (water storage tank 5, water pump 6, radiator 7, etc.), a steam generation and injection unit (including nozzle 10), an intelligent temperature control unit (controller 8, temperature sensor 9), and an auxiliary combustion unit (burner 11, gas valve 12, combustion fan 13).

[0026] The heat storage-heat exchange core unit 1 includes an external metal heat exchanger and a gradient porous solid waste-based composite heat storage material 2 filled inside it; the external metal heat exchanger is made of a high thermal conductivity copper alloy, and its inner wall is provided with an integrally formed Fibonacci tree-shaped fin 3; the gradient porous solid waste-based composite heat storage material 2 is tightly embedded between the tree-shaped fins 3 and the internal cavity, forming a tree-shaped fin-porous layer coupled enhanced heat transfer structure; the outer side of the external metal heat exchanger tube is wrapped with a glass fiber vacuum insulation layer 4.

[0027] The hydraulic circulation unit includes a water storage tank 5, a water pump 6, the heat storage-heat exchange core unit 1, an outlet valve 14, and several branch pipes connected to the rear end of the outlet valve 14 and the user-side radiator, all connected in sequence by pipes.

[0028] The steam generation and injection unit includes a steam generator 15, a steam pipeline, a steam control valve 16, and a nozzle 10; the steam generated by the steam generator 15 is transported through the steam pipeline and injected by the nozzle 10 into the inlet or internal space of the heat storage-heat exchange core unit 1.

[0029] The intelligent temperature control unit includes a temperature sensor 9, a flow sensor, and a controller 8. The temperature sensor 9 is arranged at key points inside the heat storage material and at the inlet and outlet of the heat exchange pipe. The flow sensor is installed in the hydraulic circulation unit pipe and the steam pipe. The controller 8 is electrically connected to the temperature sensor 9, the flow sensor, the water pump 6, the water outlet valve 14, the steam control valve 16, and the nozzle 10.

[0030] The system also includes an auxiliary combustion unit, comprising a burner 11, a gas supply pipeline and a gas valve 12 connected to an external gas source, and a combustion-supporting fan 13 and a fan valve for providing combustion-supporting air to the burner 11. The controller 8 is also connected to the gas valve 12 and the fan valve. The steam generator can be integrated around the auxiliary combustion unit to utilize the heat generated by the combustion in the auxiliary combustion unit.

[0031] The preparation process of the gradient porous solid waste-based composite thermal storage material 2 is as follows: Raw material pretreatment and mixing: Fly ash (particle size D50=20μm) and metallurgical slag powder (particle size D50=45μm) are mixed at a mass ratio of 6:4. Weigh 1000g of the mixed powder, add 5wt% polyvinyl alcohol aqueous solution (concentration 10%) as a binder and 8wt% ammonium bicarbonate as a pore-forming agent, and mix thoroughly.

[0032] Gradient vibration molding: The mixture is filled into a special mold and pressed into a cylindrical preform of Φ150mm ×100mm under a vibration frequency of 50Hz. Through process control, a gradient structure with decreasing porosity from the surface to the inner layer is formed.

[0033] Sintering: The preform is placed in a sintering furnace and heated to 950°C at a rate of 8°C / min under nitrogen protection. It is held at that temperature for 2 hours and then cooled with the furnace.

[0034] Sintering: The sintered body is heated to 500°C in air at a rate of 3°C / min and held for 1.5 hours to completely remove organic components.

[0035] Vacuum impregnation: Sodium nitrate-potassium nitrate eutectic salt (mass ratio 60:40) and 1 wt% nanographite sheets are melt-mixed at 220℃. The gradient porous matrix is ​​placed in an impregnation tank and the vacuum is drawn to below 10 Pa. Molten slurry is then injected for thorough impregnation.

[0036] Post-treatment: After impregnation, the material is dried at 70°C for 3 hours, and then heat-treated at 130°C for 1 hour.

[0037] The material properties obtained in this embodiment were tested and found to be: phase change temperature 170℃, thermal conductivity 1.4 W / (m·K), and high-temperature heat storage density 0.92 J / (kg·K).

[0038] The external metal heat exchanger is made of T2 copper with a thermal conductivity of λ≈237 W / (m·K) and features Fibonacci tree-shaped fins. The intelligent temperature control unit has a temperature sensor sampling frequency of 1.5Hz, and the steam injection rate during cold start-up can be adjusted between 1 and 2 kg / s.

[0039] Figure 2This is a schematic diagram of the structure of a gradient porous solid waste-based thermal storage material. Phase change material 18 is filled in the solid waste matrix skeleton 17, and the heat flow path 19 flows from the surface high porosity region 20 through the middle medium porosity region 21, and then to the inner low porosity region 22.

[0040] Example 2: A simplified system suitable for intermittent solar heating This embodiment simplifies the solar heating scenario by removing the auxiliary combustion unit and relying entirely on the solar collector to generate superheated steam.

[0041] The core of the system includes a thermal storage-heat exchange core unit 1, a hydraulic circulation unit, and an enhanced intelligent temperature control unit. The thermal storage material is prepared using Class II fly ash, forming a gradient structure with a surface high-porosity zone 20 with a porosity of 85% (15mm thick), a middle medium-porosity zone 21 with a porosity of 70% (30mm thick), and an inner low-porosity zone with a porosity of 55% (55mm thick), filled with NaNO3-KNO3 (60:40) eutectic salt (phase change temperature 220℃).

[0042] The controller 8 integrates a solar irradiance prediction model. When the solar steam temperature is ≥150℃ and the thermal storage material temperature is ≤50℃, a cold start procedure is initiated, with an initial steam injection rate of 1.5 kg / s, which is then maintained at 0.8 kg / s via PID control. Actual measurements show that in an environment of -5℃ and with an initial water temperature of 8℃, the system can raise the outlet water temperature to above 65℃ within 15 minutes, achieving a daily average solar thermal conversion efficiency of 68%.

[0043] Example 3: Large-scale system for high-temperature waste heat recovery in the metallurgical industry This embodiment is designed as a large-scale thermal storage system with a total capacity of 15MWh for recovering the waste heat of continuously cast billets at 600-800℃ and the waste heat of flue gas at 400-550℃ in steel plants.

[0044] The thermal storage material is prepared from converter steel slag and blast furnace slag into a gradient structure with a surface porosity of 75%, a middle porosity of 60%, and an inner porosity of 45%, and is filled with a ternary eutectic salt of NaCl-KCl-MgCl2 (phase change temperature 385℃, latent heat value 285 kJ / kg).

[0045] The external metal heat exchanger is made of Incoloy 800H high-temperature alloy, with internal fourth-order fractal optimized fins. The intelligent temperature control unit is equipped with a dense sensor network, which intelligently switches heat sources and distributes heat (process hot water, heating, and cooling drive) according to the production rhythm.

[0046] The system takes about 45 minutes to start up from cold to full load, has a waste heat recovery efficiency of 72%, a thermal efficiency of ≥88% for the thermal storage system, and reduces CO2 emissions by about 4,860 tons per year.

[0047] Cold start procedure description (in conjunction with) Figure 3 ): The process begins with system startup. First, the thermal storage material is preheated, and water pump 6 circulates water into the system. If the temperature is insufficient, a steam-assisted rapid heating (underwater ignition) stage is initiated, where steam is injected to directly heat the core. Controller 8 continuously monitors the temperature and selects the appropriate mode: if the requirements are met, the system begins operation; if a stronger heat source is needed, pneumatic pulse ignition is triggered to start the burner 11. After operation, the system is shut down safely, and the process ends. This process ensures a rapid, stable, and safe cold start.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2), characterized in that, include: The heat storage-heat exchange core unit (1), the hydraulic circulation unit, the steam generation and injection unit, and the intelligent temperature control unit; The heat storage-heat exchange core unit (1) includes an external metal heat exchanger and a gradient porous solid waste-based composite heat storage material (2) filled inside it; the external metal heat exchanger is made of a high thermal conductivity copper alloy, and its inner wall is provided with an integrally formed Fibonacci tree-shaped fin (3); the gradient porous solid waste-based composite heat storage material (2) is tightly embedded between the tree-shaped fins (3) and the internal cavity to form a tree-shaped fin (3)-porous layer coupled enhanced heat transfer structure; The hydraulic circulation unit includes a water storage tank (5), a water pump (6), the heat storage-heat exchange core unit (1), a water outlet valve (14), and several branch pipes connected to the rear end of the water outlet valve (14) and a user-side radiator (7) connected in sequence through pipes. The steam generation and injection unit includes a steam generator (15), a steam pipeline, a steam control valve (16), and a nozzle (10); the steam generated by the steam generator (15) is transported through the steam pipeline and injected by the nozzle (10) into the inlet or internal space of the heat storage-heat exchange core unit (1); The intelligent temperature control unit includes a temperature sensor (9), a flow sensor, and a controller (8); the temperature sensor (9) is arranged at key points inside the heat storage material and at the inlet and outlet of the heat exchange pipe; the flow sensor is set in the hydraulic circulation unit pipe and the steam pipe; the controller (8) is electrically connected to the temperature sensor group (9), the flow sensor, the water pump (6), the outlet valve (14), the steam control valve (16), and the nozzle (10), respectively.

2. The intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2) according to claim 1, characterized in that, The system also includes an auxiliary combustion unit, including a burner (11), a gas supply pipeline and a gas valve (12) connected to an external gas source, and a combustion air blower (13) and a blower valve for providing combustion air to the burner (11); the controller (8) is also connected to the gas valve (12) and the blower valve; the steam generator (15) can be integrated around the auxiliary combustion unit to utilize the heat generated by the combustion of the auxiliary combustion unit.

3. The intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2) according to claim 1, characterized in that, The gradient porous structure contained in the gradient porous material (2) exhibits a distribution of porosity that decreases gradually from the surface to the interior along the thickness direction. Specifically, the surface layer is a high-porosity region (20) with a porosity >70%, which is conducive to rapid heat exchange with the air or steam side; the middle layer is a medium-porosity region (21) with a porosity of 50%-70%, serving as a transition layer; and the inner layer is a low-porosity region with a porosity <50%, which is conducive to efficient heat transfer with the heat exchange tube wall and the water side.

4. The intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2) according to claim 3, characterized in that, The porosity distribution of the gradient porous structure is as follows: surface porosity 80%, middle porosity 65%, and inner porosity 50%.

5. The intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2) according to claim 1, characterized in that, The preparation method of the gradient porous solid waste-based composite thermal storage material (2) includes the following steps: Step 1: Vibration molding: Mix industrial solid waste powder with binder and pore-forming agent in a certain proportion; vibrate at a specific frequency and amplitude to press into a preform with a preset porosity gradient; Step 2: Sintering: Place the preform in a sintering furnace and heat it to 800-1100℃ at a rate of 5-10℃ / min under a protective atmosphere of nitrogen or argon. Hold it at this temperature for 1-3 hours to form a metallurgical bond between the powder particles. Step 3: Inhalation: Under air atmosphere, the temperature is raised to 400-600℃ at a heating rate of 1-5℃ / min and held for 1-2 hours to allow the organic binder and pore-forming agent added in Step 1 to fully decompose and be discharged, forming a rigid solid waste matrix skeleton with a gradient porous structure (17). Step 4: Vacuum impregnation: The molten sodium nitrate-potassium nitrate eutectic salt phase change material (18) and the uniform slurry composed of nano-reinforcing particles are impregnated into the gradient porous solid waste matrix skeleton under vacuum conditions; Step 5: Post-treatment: The impregnated composite material is dried and then heat-treated at 120~150℃ to finally obtain a gradient porous solid waste-based composite thermal storage material (2).

6. The intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2) according to claim 5, characterized in that, In step 1, the industrial solid waste powder is fly ash or metallurgical slag with a particle size of 1μm to 100μm; the binder is a polyvinyl alcohol aqueous solution; the pore-forming agent is ammonium bicarbonate; and the frequency is 50Hz.

7. The intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2) according to claim 5, characterized in that, In step 5, the impregnated composite material is dried at 60-80°C for 2-4 hours, and then heat-treated at 120-150°C for 0.5-1 hour.

8. The intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2) according to claim 5, characterized in that, In step 4, the nano-reinforcing particles are graphene or silicon carbide.

9. The intelligent temperature control system based on gradient porous solid waste-based composite thermal storage material (2) according to claim 1, characterized in that, The performance indicators of the gradient porous solid waste-based composite thermal storage material (2) are as follows: high-temperature thermal storage density ρ = 0.8~1.0 J / (kg·K), phase change melting temperature T = 150~200℃, thermal conductivity λ = 1.3~1.5 W / (m·K), and volume expansion coefficient α ≈ 1.5×10 -5 / K.

10. The cold start optimization method for the intelligent temperature control system according to claim 1, characterized in that, Includes the following steps: S1. System self-check and preheating: The system starts and the controller (8) performs equipment self-check; the water pump is started and the water pump (6) in the water storage tank (5) is put into the heat storage-heat exchange core unit (1) to preheat the internal heat storage materials and pipes; S2, Steam-assisted rapid heating and underwater ignition: When the initial temperature of the heat storage material is detected to be low, the controller (8) starts the steam generation and injection unit; the nozzle (10) injects superheated steam with a flow rate of 1~2 kg / s into the heat storage unit. The steam condenses and releases heat in the porous structure of the material, realizing rapid and uniform "underwater ignition" heating and avoiding local overheating. S3, Intelligent temperature judgment and fuel switching: The temperature sensor monitors the temperature of the heat storage material and the outlet in real time; when the temperature reaches the preset primary threshold, the controller (8) can adjust the steam injection amount or close the steam valve; if it is necessary to further increase the temperature or the steam heat source is insufficient, the auxiliary combustion unit will be started. S4, Pneumatic high-pulse ignition: The controller (8) executes the step-by-step ignition procedure in sequence: a) First, a small amount of atomized steam is injected into the burner (11) area to preheat the combustion chamber and establish a stable ignition environment; b) Then, the gas valve (12) is opened to inject gas, and the gas is ignited by the electric igniter or the high-temperature environment after stabilization to form a stable flame; c) After the combustion is stable, the steam injection is stopped; This process ensures reliable ignition and no flameout in the cold state through steam piloting; S5. System steady-state operation: When the outlet water temperature reaches the set working temperature, the controller (8) closes the heating valve gas / steam valve and opens the outlet valve (14) to distribute hot water to each user side radiator (7) as needed, and the system enters a stable heating state. S6. System shutdown and safety protection: After the user stops using heat or the target is reached, the controller (8) shuts down the gas valve (12), fan valve, water pump (6), etc. in sequence to ensure the safe shutdown of the system.

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