Intelligent temperature control system and method for concrete matrix of fire pump station

Abstract

The invention relates to the technical field of constructional engineering, and discloses an intelligent temperature control system for a concrete matrix of a fire pump station, the intelligent temperature control system comprises a composite phase change core body, an encapsulation layer and a nanofiber layer which are compounded in the concrete matrix, and the encapsulation layer is arranged outside the composite phase change core body in a wrapping manner to form a microcapsule; the nanofiber layer is distributed outside the packaging layer in a three-dimensional network mode to form a three-dimensional heat conduction channel, a fiber grating sensor used for collecting multi-modal data and a piezoelectric ceramic element used for supplying electric energy are integrated in the three-dimensional heat conduction channel, and the multi-modal data are received through an LSTM training model and temperature field changes are predicted. Therefore, the composite phase-change core body is driven to perform phase-state conversion. The problems that traditional concrete is low in heat conduction efficiency, complex in arrangement of cooling water pipes and high in cost are solved in a breakthrough mode, meanwhile, the problem of temperature stress cracks caused by hydration heat of mass concrete is solved, and self-adaptive temperature intelligent regulation and control of the fire pump station are achieved.

Description

Technical Field

[0001] This invention relates to the field of building engineering technology, specifically to an intelligent temperature control system and method for concrete substrates in fire pump stations. Background Technology

[0002] With the development of intelligent building materials, the engineering field urgently needs composite systems that combine efficient temperature control, mechanical reinforcement, and self-healing functions. Simultaneously, the expansion of building construction scale places higher demands on improving fire safety. Fire pump stations play a crucial role in urban flood control and drainage, as well as fire-fighting water supply for industrial facilities; their fire protection structure directly affects the efficiency and stability of the pump stations.

[0003] In the concrete engineering of flow channel structures in large fire pump stations, traditional temperature control technologies, which rely on passive heat dissipation or complex external systems, are ill-equipped to address the structural risks posed by the continuous heat release from the equipment and the temperature difference with the environment. Specific problems include: 1. Traditional concrete has extremely low thermal conductivity, leading to frequent temperature stress cracks. Traditional concrete has a thermal conductivity of only 1.5 W / m·K, which cannot quickly conduct the heat generated by the operation of equipment (the local temperature of a fire pump unit can reach more than 60°C when it is running). This results in the internal and surface temperature difference often exceeding 25°C, far exceeding the 20°C limit allowed by the standard. The concrete may develop through cracks due to the superposition of hydration heat and equipment heat release. 2. External temperature control systems consume a lot of energy and are complex to maintain. Traditional solutions rely on pre-embedded cooling water pipes or air conditioning equipment, which have high installation and construction costs. Furthermore, the water pipes are prone to cracking due to concrete shrinkage, which in turn leads to water erosion of the concrete base layer and reduced strength, resulting in significant rework losses. In addition, air conditioning systems have a high failure rate in high humidity environments (the humidity of pumping stations often exceeds 85%). 3. Lack of intelligent response mechanism, resulting in significant temperature control lag. Traditional temperature control relies on manual inspection and adjustment. However, manual inspection has a lag in detecting microcracks, and in low-temperature winter environments, traditional systems cannot predict nighttime temperature drops. The sudden drop in concrete surface temperature causes temperature stress, resulting in radial cracks around the valve well, affecting the equipment installation accuracy and causing significant rework and debugging losses.

[0004] As fire pump stations develop towards larger scale and greater intelligence (such as unmanned pump stations), the shortcomings of traditional temperature control technology in terms of safety, economy, and adaptability have become key factors restricting the lifespan of the project. There is an urgent need to propose an innovative solution for an intelligent temperature control system for fire pump stations containing phase change materials and nanocomposite fibers to break through the bottleneck. Summary of the Invention

[0005] To address the technical problems existing in the background art, the present invention proposes an intelligent temperature control system and method for concrete substrates in fire pump stations.

[0006] This invention proposes an intelligent temperature control system for concrete substrates in fire pump stations, comprising a composite phase change core, an encapsulation layer, and a nanofiber layer embedded in the concrete substrate. The encapsulation layer is disposed on the outside of the composite phase change core to form a microcapsule. The nanofiber layer is distributed in a three-dimensional network on the outside of the encapsulation layer to form a three-dimensional heat conduction path. The three-dimensional heat conduction path integrates a fiber optic grating sensor for acquiring multimodal data and a piezoelectric ceramic element for power supply. The system receives multimodal data and predicts temperature field changes through an LSTM-trained model to drive the composite phase change core to undergo phase transition. By utilizing the latent heat balance of the phase transition and the local temperature difference, the system achieves integrated temperature control of phase change energy storage, nano-thermal conduction, and intelligent response. To address the problems of traditional fire pump station concrete structures being prone to thermal stress cracks due to temperature fluctuations, relying on external power supplies, and having low temperature control efficiency, this system achieves intelligent temperature control through a collaborative approach of "materials-structure-algorithm." A composite phase change core serves as the energy storage core, an encapsulation layer forms microcapsules to prevent leakage, and a nanofiber layer constructs a three-dimensional thermally conductive network to accelerate heat transfer. The combination of these three elements increases the thermal conductivity of the concrete to 5.2 W / m·K, compared to only 1.5 W / m·K for traditional concrete. Fiber optic grating sensors collect temperature and stress data in real time with an accuracy of ±0.1℃. Piezoelectric ceramic elements generate electricity using structural vibrations, with a power output ≥0.5 mW / cm². 3 Without requiring an external power source, the LSTM model predicts the peak temperature field within 1 hour, driving the phase change material to absorb / release heat in the 25-40℃ range, with a phase change enthalpy ≥180kJ / kg, controlling the local temperature difference within 5℃, and reducing temperature control delay by 80% compared to traditional technologies. It should be noted that the fire pump station is equipped with an industrial-grade ARM architecture embedded microprocessor, which loads LSTM training models and algorithms.

[0007] As a further optimization of this invention, the composite phase change core is a paraffin-fatty acid eutectic phase change material core. The paraffin-fatty acid eutectic material, through precise proportioning (e.g., 60% paraffin and 40% fatty acid), forms a eutectic mixture of the two components, which can regulate the phase change temperature to approximately 32°C (suitable for fire pump station environments). The phase change enthalpy reaches 195 kJ / kg, enabling efficient absorption of heat generated during equipment operation. The eutectic structure avoids the phase separation problem of single phase change materials, and after 500 cycles, the thermal performance decay is ≤5%, ensuring long-term stability. The phase transition temperature and latent heat of eutectic mixtures can be controlled by adjusting the component ratios, thus precisely controlling the phase transition temperature of eutectic phase change materials to meet different application requirements.

[0008] As a further optimization of the present invention, the encapsulation layer is a uniform and dense coating layer formed by depositing a boehmite solution on the surface of the composite phase change core. Boehmite (AlOOH) coating is deposited via sol-gel method, with a thickness of 5-10 μm and a density of over 98%, which can prevent leakage of phase change materials in the molten state. At the same time, boehmite has excellent compatibility with cement matrix, and the interfacial bonding strength is improved by 30%, avoiding the decrease in structural strength caused by material separation.

[0009] As a further optimized solution of the present invention, the nanofiber layer is silicon carbide nanofiber with a diameter of 50-200nm and an aspect ratio of 200:1. The silicon carbide nanofiber is pre-dispersed in the polycarboxylate superplasticizer solution by ultrasonic oscillation technology to form a uniform suspension, ensuring the three-dimensional network distribution of silicon carbide nanofiber in concrete. Silicon carbide nanofibers (tensile strength ≥1000MPa, elastic modulus 300GPa) are dispersed in concrete by ultrasonic oscillation (power 500W, time 30 minutes) to form a continuous thermally conductive network, which improves thermal conductivity by 200%. The three-dimensional distribution design increases the contact area between the fiber and the concrete matrix by 40%, and at the same time, it inhibits crack propagation through the "bridging effect", which increases the tensile strength of concrete by 40%.

[0010] As a further optimization of the present invention, the nanofiber layer in the three-dimensional network densification part of silicon carbide nanofibers is gradient distributed along the principal stress direction and is suitable for the part with a bending radius ≤1.5m. This design is based on the overall distribution of a three-dimensional network, and the density is optimized according to the stress characteristics of the structure. The fiber density is increased along the principal stress direction, so that the network structure is more in line with the actual stress requirements. The combination of gradient distribution and three-dimensional network not only ensures the efficient transfer of heat in the overall structure, but also improves the tensile strength of concrete through fiber reinforcement in stress concentration areas. At the same time, it avoids material waste caused by excessive fiber in non-stress areas. This allows the three-dimensional network to not only meet the thermal conductivity function, but also enhance the functionality and adaptability of the three-dimensional network. Specifically, in stress concentration areas such as bends and corners of pump stations, nanofibers are oriented along the principal stress direction (accounting for 2% of the volume), while non-stress areas account for 1%, forming a gradient distribution. This design improves the crack resistance of bends by 50%, adapts to complex structures with curvature radii ≤ 1.5m, solves the problem of uneven temperature control in irregularly shaped parts, and incorporates 5%-8% paraffin-fatty acid eutectic phase change material in stress concentration areas to specifically absorb local thermal stress.

[0011] As a further optimization of the present invention, the outer coating of the nanofiber layer is provided with an MFI zeolite molecular sieve coating, which is used for catalytic degradation of pollutants and humidity regulation. MFI zeolite molecular sieve coating (thickness 5-10μm) has a microporous structure with a pore size of 0.55nm, which can adsorb and catalytically degrade pollutants such as formaldehyde and VOCs (degradation rate ≥90%). At the same time, its hydrophilicity enables humidity regulation (humidity control range 40%-60%), avoiding equipment corrosion caused by high humidity environment and extending the service life of pump station. When volatile organic compounds (VOCs), formaldehyde, benzene, and other pollutants come into contact with the MFI zeolite molecular sieve coating, the pollutant molecules enter the microporous channels of the zeolite. Within these microporous channels, the pollutant molecules react chemically with the active acidic sites on the zeolite surface and are catalytically decomposed into harmless carbon dioxide and water vapor. Furthermore, the surface of the MFI zeolite molecular sieve coating is equipped with a microbial repair agent (alkaliphilic Bacillus + magnesium phosphate cement), which triggers the formation of magnesium carbonate crystals when the humidity is >80%. The crack repair rate is ≥85% after 28 days, forming a four-dimensional protection mechanism of "heat absorption-heat conduction-humidity regulation-repair" to prevent cracks from penetrating the structure.

[0012] As a further optimization of the present invention, both the fiber optic grating sensor and the piezoelectric ceramic element are arrayed. The fiber optic grating sensor monitors the temperature of the stress concentration zone inside the concrete matrix in real time, and the piezoelectric ceramic element is combined with the structure vibration to generate electricity to form an intelligent monitoring network. The fiber optic grating sensor array has a spacing of ≤1.5m and is mainly arranged at joints or corners. It can simultaneously monitor temperature and strain (strain resolution 1με). The piezoelectric ceramic elements are distributed in a honeycomb pattern and generate electricity using the mechanical energy generated by water flow vibration or equipment operation. The energy is stored in a microcapacitor module to power the sensor and control system, forming a "self-sensing-self-powering" closed loop. Through real-time linkage between the fiber optic grating sensor and the intelligent control system, it achieves an adaptive adjustment capability that traditional active temperature control technology cannot match, reducing energy consumption by more than 35% and solving the functional failure problem caused by thermal stress cracking in the temperature control structure of traditional fire pump stations.

[0013] As a further optimization of the present invention, the fiber optic grating sensor is divided into two parts. The first part is embedded in the interlayer of the nanofiber layer in a spiral shape with a spacing of 10-20 mm, covering more than 80% of the volume of the phase change material. The second part is distributed on the surface of the encapsulation layer in both axial and circumferential dimensions. The axial grating spacing is 50 mm, and one set is arranged every 120° in the circumferential direction to realize the three-dimensional reconstruction of the temperature field gradient. A spiral sensor (covering 80% of the phase change material) captures data from the core temperature control zone. A dual-dimensional distributed sensor constructs a three-dimensional temperature field model (spatial resolution 0.5m×0.5m). Through data fusion, it can accurately locate abnormal temperature differences (error ≤0.5℃), providing high-precision input for the LSTM model and improving the prediction accuracy to over 90%.

[0014] As a further optimization of the present invention, the piezoelectric ceramic element adopts a multi-layer stacked arrangement and is distributed in a honeycomb array. The multi-layer stacked design increases the power generation of the piezoelectric ceramic to 0.8 mW / cm². 3 (Single layer only 0.2mW / cm) 3 The honeycomb array (10cm spacing) ensures uniform energy collection. When the pump station is running normally, the annual power generation of a single element can reach 5Wh, which meets the annual energy consumption requirements of the sensor network. At the same time, the wavelength shift of the fiber optic grating sensor is triggered by deformation.

[0015] A smart temperature control method for concrete substrates in fire pump stations, comprising the following steps: S1 uses the sol-gel method to encapsulate paraffin-fatty acid eutectic phase change material (melting point 32℃, phase change enthalpy 195kJ / kg) in a boehmite shell to form microcapsules with a particle size of 2-5mm. Boehmite nanoparticles are uniformly dispersed in an isopropanol-water mixed solvent to form a boehmite solution. The isopropanol-water mixed solvent is formed by mixing isopropanol and water at a mass ratio of 5:1 to 20:1 to create a moderately polar environment and ensure the dispersion stability of the boehmite nanoparticles. Then, the boehmite solution is mixed with paraffin-fatty acid eutectic particles at a mass ratio of 1:3 to 1:5 and ultrasonically dispersed for 30 minutes (300W power, 40kHz frequency) to ensure uniform suspension of the particles. Finally, the mixture is formed into micron-sized droplets by a centrifugal atomizer. After the solvent evaporates, the boehmite particles are deposited on the surface of the phase change material to form a coating layer with a thickness of 0 to 200 nm. The coating thickness can be precisely controlled by adjusting the solution concentration. S2 uses silicon carbide nanofibers with a diameter of 50-200nm and an aspect ratio of 200:1. These nanofibers are pre-dispersed in a polycarboxylate superplasticizer solution using ultrasonic oscillation technology to form a uniform suspension, ensuring a three-dimensional network distribution of the fibers in the concrete. The silicon carbide nanofibers have extremely high tensile strength, reaching over 1000MPa, and also possess a high elastic modulus of approximately 300GPa, enabling them to withstand large mechanical loads. The fiber network formed by the silicon carbide nanofibers can also inhibit crack propagation through the fiber bridging effect. S3 uses sulfoaluminate low-heat cement mixed with 30% fly ash, and incorporates 5% phase change microcapsules in the core area and 2% nanofiber suspension in the middle layer. The surface is sprayed with a 5-10μm thick MFI zeolite molecular sieve coating to form a "heat absorption-heat conduction-humidity regulation" sandwich structure. S4 features a pre-embedded distributed fiber Bragg grating sensor with an accuracy of ±0.1℃ and a power generation capacity ≥0.5mW / cm² within the template. 3Piezoelectric ceramic elements, with a sensor spacing of ≤1.5m, are mainly placed in structural stress concentration areas such as corners and joints. The piezoelectric ceramic elements generate electricity through vibration triggered by concrete pouring, and the energy is stored in a micro capacitor module to power the temperature control feedback system without the need for an external power source. S5 captures temperature changes through the LSTM neural network algorithm and adopts a multi-step prediction strategy to predict the peak distribution of the temperature field in the next hour, triggering the phase transition threshold of the phase change material. Based on the prediction results, it drives the endothermic / exothermic behavior of the paraffin-fatty acid eutectic phase change material and balances the local temperature difference through the latent heat of phase transition (≥180kJ / kg). This method combines material layering design with intelligent algorithms to achieve full life-cycle temperature control. The "sandwich structure" constructed in steps S1-S3 enables concrete to have energy storage, heat conduction and environmental protection functions. The self-powered monitoring network in step S4 reduces operation and maintenance costs. The LSTM prediction strategy in step S5 (multi-step prediction error ≤2℃) achieves active temperature control, which reduces energy consumption by 55% compared with traditional passive cooling. In practical applications, the temperature difference between the inside and outside of the concrete in the pump station can be reduced from the traditional 28-35℃ to within 5℃, and the occurrence rate of thermal stress cracks can be reduced by 90%.

[0016] The intelligent temperature control system and method for concrete substrates in fire pump stations proposed in this invention have the following beneficial effects: (i) By setting an encapsulation layer on the outside of the composite phase change core, microcapsules containing paraffin-fatty acid eutectic phase change material are formed. The microcapsules are then combined with silicon carbide nanofibers in the concrete matrix. The paraffin-fatty acid eutectic phase change material has a melting point of 25-40℃ and a phase change enthalpy of ≥180kJ / kg. This constructs a sandwich structure with gradient functional characteristics. The composite phase change core regulates the local temperature difference through heat absorption / release. The nanofiber network in the middle layer forms a three-dimensional heat conduction path, which improves the thermal conductivity. The outer zeolite molecular sieve coating has both humidity control and pollutant degradation functions. This breakthrough solves the limitations of traditional concrete with low thermal conductivity and complex and costly cooling water pipe layout. It also solves the problem of temperature stress cracks caused by hydration heat in large-volume concrete, realizing adaptive temperature intelligent control of fire pump stations. (ii) By integrating an embedded fiber optic grating sensor array and piezoelectric ceramic elements into a three-dimensional heat conduction path, and using an LSTM neural network algorithm to predict temperature field changes, the phase transition response time of the phase change material is driven to be ≤5 minutes, forming an adaptive temperature control feedback system that does not require external power supply. The silicon carbide nanofibers are oriented along the stress direction, which increases the tensile strength by 40% while reducing the amount of phase change material by 20%. This achieves the integration of nanoscale thermal conductivity enhancement, gradient functional design and intelligent predictive control, solving the core problems of low thermal conductivity and reliance on external power supply in traditional materials.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] Figure 1 This is a structural schematic diagram of the intelligent temperature control system for concrete substrates in fire pump stations provided by the present invention. Figure 2 This is a schematic diagram of the three-dimensional heat conduction path of the intelligent temperature control system for concrete substrates in fire pump stations provided by the present invention. Figure 3 This is a schematic diagram illustrating the logic principle of the intelligent temperature control system for concrete substrates in fire pump stations provided by the present invention.

[0019] Figure descriptions: 1. Composite phase change core; 2. Encapsulation layer; 3. Nanofiber layer; 4. MFI zeolite molecular sieve coating; 5. Three-dimensional thermal conduction path; 6. Fiber grating sensor; 7. Piezoelectric ceramic element. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0021] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0022] Please see Figures 1-3 The specific implementation of an intelligent temperature control system for concrete substrates in fire pump stations is as follows: This intelligent temperature control system is based on a three-in-one approach of "materials-structure-algorithm". Through the synergy of the composite phase change core 1, the nanofiber layer 3, and the intelligent monitoring network, it achieves adaptive temperature regulation of the concrete matrix of the fire pump station. The system forms a gradient functional structure from the inside out. (a) The inner layer is a paraffin-fatty acid eutectic phase change material microcapsule (encapsulation layer 2), which absorbs or releases latent heat through phase transition; (b) The middle layer is a three-dimensional thermally conductive pathway 5 constructed of silicon carbide nanofibers 3, which accelerates heat transfer; (c) The outer layer is an MFI zeolite molecular sieve coating 4, which has both humidity regulation and pollutant degradation functions; The three-dimensional heat conduction path 5 integrates a fiber optic grating sensor 6 and a piezoelectric ceramic element 7. The former collects temperature and stress data in real time, while the latter generates power using structural vibration. Combined with the LSTM neural network algorithm, it predicts temperature field changes and drives the dynamic response of the phase change material, forming a closed-loop temperature control system that does not require external power supply. Specifically, during the operation of the fire pump station, the equipment generates a large amount of heat, causing the internal temperature of the pump station to rise. At this time, the paraffin-fatty acid eutectic phase change material microcapsules in the composite phase change core near the heat source sense the temperature change. When the temperature reaches the phase change temperature (about 32°C), the phase change material changes from solid to liquid, absorbing a large amount of latent heat and slowing down the temperature rise of the concrete matrix. In this process, the three-dimensional heat conduction pathway formed by silicon carbide nanofibers in the nanofiber layer plays a key role. Like a highway, it quickly transfers the heat absorbed by the phase change material to the surrounding area, expanding the heat dissipation range and avoiding excessive local temperature. At the same time, the outer MFI zeolite molecular sieve coating regulates the ambient humidity to prevent excessive humidity from affecting the operation of the equipment, and degrades pollutants in the air to maintain good air quality in the pump station. Furthermore, the fiber optic grating sensor 6 continuously monitors the temperature and stress data at different locations in the concrete matrix and transmits this data to the internal algorithm system in real time. The piezoelectric ceramic element 7, under the vibration generated by the operation of the pump station equipment, converts mechanical energy into electrical energy through its own piezoelectric effect and stores it in the micro-capacitor module, providing power support for the entire intelligent monitoring network and algorithm operation, ensuring that the system can work continuously and stably without external power supply. Specifically, the composite phase change core 1 adopts a paraffin-fatty acid eutectic system (60% paraffin and 40% fatty acid). Through precise proportioning, the phase change temperature is controlled to about 32°C, and the phase change enthalpy reaches 195kJ / kg. It can efficiently absorb the heat generated by the operation of the equipment. The eutectic structure avoids the phase separation problem of single phase change materials. After 500 cycles, the thermal performance decay is ≤5%, ensuring long-term stability. Furthermore, a boehmite (AlOOH) coating layer (5-10 μm thick) is deposited on the surface of the phase change material using the sol-gel method to form microcapsules with a particle size of 2-5 mm. The density of the boehmite coating layer reaches over 98%, preventing the phase change material from melting and leaking. At the same time, the interfacial bonding strength with the cement matrix is ​​increased by 30%, avoiding the decrease in structural strength caused by material separation. In the actual preparation process, paraffin wax and fatty acids are first mixed in a precise ratio and allowed to fully eutecticly melt under specific temperature and stirring conditions to form a uniform eutectic liquid phase. Then, this liquid phase is slowly dripped into a reaction solution containing boehmite precursor. Through sol-gel reaction, a uniform boehmite coating layer is gradually formed on the surface of the phase change material droplets. After subsequent curing, cleaning and drying processes, composite phase change microcapsules with a particle size between 2-5 mm are obtained. These microcapsules can be uniformly dispersed in the cement matrix during concrete mixing and stably play a phase change temperature control role when the temperature changes. Specifically, the nanofiber layer uses silicon carbide nanofibers with a diameter of 50-200 nm and an aspect ratio of 200:1, with a tensile strength ≥1000 MPa and an elastic modulus of 300 GPa. These nanofibers are pre-dispersed in a polycarboxylate superplasticizer solution via ultrasonic oscillation (500 W power, 30 minutes) to form a uniform suspension. The nanofiber layer constructs a three-dimensional network. Based on the overall distribution of the three-dimensional network, density optimization is performed to address the structural stress characteristics, increasing fiber density along the principal stress direction. This makes the network structure more closely match actual stress requirements, enhancing the functionality and adaptability of the three-dimensional network. The fibers are distributed in a gradient along the principal stress direction in the concrete: 2% volume in stress concentration areas (such as bends and corners) and 1% in non-stress areas. This adapts to complex locations with a curvature radius ≤1.5 m, inhibiting crack propagation through a "bridging effect" and increasing the tensile strength of the concrete by 40%. By constructing a three-dimensional network structure using silicon carbide nanofibers, the thermal conductivity of concrete is increased from the traditional 1.5 W / m·K to 5.2 W / m·K, improving heat transfer efficiency by 200% and solving the problem of thermal lag in traditional concrete. In the actual preparation process, silicon carbide nanofibers are first added to a polycarboxylate superplasticizer solution. Using an ultrasonic oscillation device, the solution is oscillated at 500W for 30 minutes to ensure the fibers are evenly dispersed in the solution, forming a stable suspension. Before concrete pouring, this suspension is added to the concrete mix according to the designed ratio. Mechanical stirring is used to initially disperse the nanofibers in the concrete. During pouring, special pouring techniques and vibration methods are employed for stress-concentrated areas such as bends and corners to ensure that the nanofibers form a higher density distribution (reaching a volume percentage of 2%) along the principal stress direction in these areas, while maintaining a 1% volume percentage in non-stress areas. In this way, the nanofibers intertwine within the concrete, constructing a three-dimensional thermal conductivity network, greatly improving the thermal conductivity of the concrete, effectively accelerating heat transfer, and enhancing the overall response efficiency of the temperature control system. Specifically, the MFI zeolite molecular sieve coating is formed on the surface of the nanofiber layer by spraying process, with a thickness of 5-10 μm. Its microporous structure (pore size 0.55 nm) can adsorb and catalytically degrade pollutants such as formaldehyde and VOCs (degradation rate ≥90%). At the same time, the humidity is adjusted to 40%-60% through hydrophilicity to avoid equipment corrosion caused by high humidity environment. Specifically, the fiber optic grating sensor array is arranged in two parts: ① It is spirally embedded between the three nanofiber layers with a spacing of 10-20 mm, covering more than 80% of the phase change material volume and capturing data from the core temperature control zone; ② It is distributed axially (50 mm spacing) and circumferentially (1 group every 120°) on the surface of the encapsulation layer 2 to realize the three-dimensional reconstruction of the temperature field gradient, with a spatial resolution of 0.5 m × 0.5 m and a temperature measurement accuracy of ±0.1℃. When installing the fiber optic grating sensor 6, for the part embedded in the nanofiber layer 3, the sensor is carefully placed in the space between the nanofiber layers in a spiral pattern with a spacing of 10-20mm to ensure maximum coverage of the phase change material area and accurate capture of temperature changes in the core temperature control zone. For the sensors distributed on the surface of the encapsulation layer 2, they are installed according to the rule of 50mm axial spacing and 120° circumferential spacing. In this way, the temperature field of the entire concrete matrix can be reconstructed in three dimensions with a spatial resolution of 0.5m×0.5m and a temperature measurement accuracy of ±0.1℃, providing accurate temperature data for the system.

[0023] Specifically, the piezoelectric ceramic power supply uses multi-layer stacked piezoelectric ceramic elements 7, distributed in a honeycomb array (10cm spacing), to generate electricity using water flow vibration or mechanical energy from equipment operation, with an actual power ≥ 0.8mW / cm². 3 (Single layer only 0.2mW / cm) 3 Energy is stored in a miniature capacitor module to meet the annual energy consumption needs of the sensor network (the annual power generation of a single component is about 5Wh). The piezoelectric ceramic element 7 adopts a multi-layer stacked design, arranged in a honeycomb array, and is evenly distributed within the concrete structure at 10cm intervals. When the water flow in the pumping station vibrates or the equipment operation generates mechanical energy, the piezoelectric ceramic element is deformed by the vibration, generating electrical energy according to the piezoelectric effect. The multi-layer stacked design significantly increases its power generation capacity, reaching ≥0.8mW / cm². 3 (Compared to 0.2mW / cm² for a single layer) 3 (There is a significant improvement), and the generated electrical energy is stored in the connected miniature capacitor modules. These capacitor modules can stably store electrical energy to provide the energy required for intelligent monitoring network equipment such as fiber optic grating sensors throughout the year (the annual power generation of a single piezoelectric ceramic element is about 5Wh, which is sufficient to meet the energy needs of surrounding sensors), ensuring the continuous operation of the system. Specifically, the construction process and temperature control procedure are as follows: I. Material Preparation S1 phase change microcapsule preparation: Paraffin-fatty acid eutectic material was encapsulated in a boehmite shell by sol-gel method to form microcapsules with a particle size of 2-5 mm, ensuring that the coating layer is uniform and dense; Preparation of S2 nanofiber suspension: Silicon carbide nanofibers are added to a polycarboxylate superplasticizer solution and dispersed by ultrasonic oscillation to form a suspension with stable concentration; S3 gradient casting: The sulfoaluminate low-heat cement is mixed with 30% fly ash and constructed in layers. The core area is mixed with 5% phase change microcapsules, the middle layer is mixed with 2% nanofiber suspension, and the surface is sprayed with MFI zeolite molecular sieve coating to form a "heat absorption-heat conduction-humidity regulation" sandwich structure. In step S1, paraffin and fatty acids are mixed and eutecticly melted in strict proportion to obtain a eutectic material. Then, it is slowly dripped into a reaction solution containing boehmite precursor. By precisely controlling the reaction conditions, a boehmite coating layer is deposited on the surface of the eutectic material using the sol-gel method. After a series of post-processing processes, phase change microcapsules with a particle size of 2-5 mm and a uniform and dense coating layer are selected. In step S2, silicon carbide nanofibers are added to a polycarboxylate superplasticizer solution, placed in an ultrasonic oscillation device, and set to a power of 500W for 30 minutes to disperse the nanofibers evenly and form a stable suspension for later use. II. Concrete Pouring At the construction site of the fire pump station, sulfoaluminate low-heat cement and 30% fly ash are first thoroughly mixed in proportion, and then poured in layers when pouring concrete. First, pour the core area. During the concrete mixing process, add 5% phase change microcapsules to ensure their uniform distribution. This area is mainly responsible for absorbing heat. Next, the intermediate layer is poured, and 2% nanofiber suspension is added to the concrete. Vibration is then used to form a three-dimensional heat-conducting network of nanofibers. Finally, an MFI zeolite molecular sieve coating is sprayed onto the concrete surface to form a complete "heat absorption-heat conduction-humidity regulation" sandwich structure. III. Pre-embedded intelligent components Fiber optic grating sensors (6) and piezoelectric ceramic elements (7) are pre-set in the template and are mainly arranged in stress concentration areas such as corners and joints. The sensor spacing is ≤1.5m. The piezoelectric ceramic elements are triggered to generate electricity by the vibration of concrete pouring. The energy is stored in the capacitor module to provide power for system startup. After the template is erected, the construction workers carefully place fiber optic grating sensors and piezoelectric ceramic elements in the template according to the design drawings, at the corresponding stress concentration areas such as corners and joints. For the fiber optic grating sensors, they are arranged with a spacing of no more than 1.5m to ensure comprehensive monitoring of temperature and stress changes in the concrete structure. The piezoelectric ceramic elements are also distributed in these key areas. During the concrete pouring process, as the concrete is vibrated, the piezoelectric ceramic elements are subjected to vibration and begin to generate electrical energy. This electrical energy is stored in the capacitor module connected to it in a timely manner. Before the system is connected to an external power source, the electrical energy stored in the capacitor module provides energy support for the startup and initial operation of the entire intelligent temperature control system. IV. Temperature Control Logic Driven by LSTM Algorithm Data Acquisition and Prediction: Fiber Bragg grating sensors upload temperature and stress data in real time. An LSTM neural network, through a multi-step prediction strategy (inputs include historical temperature, environmental parameters, and equipment load), predicts the peak temperature field distribution one hour in advance, with a prediction accuracy of >90%. Phase change response triggering: When the predicted temperature reaches the phase change threshold (32℃), the system drives the phase change material to change from solid to liquid and absorb heat, keeping the local temperature difference within 5℃; when the temperature drops below 30℃, the material solidifies and releases heat, maintaining the matrix temperature stability, with a response delay of ≤5 minutes, shortening the temperature control lag by 80% compared to traditional technology. Fiber Bragg grating sensors collect real-time temperature and stress data and quickly upload it to a microprocessor via wired or wireless transmission. After receiving this data, the LSTM neural network model combines historical temperature data, environmental parameters within the pumping station (such as humidity and ventilation), and equipment load information, and performs calculations using a multi-step prediction strategy. After extensive data training and optimization, the model can accurately predict the peak distribution of the temperature field one hour in advance, with a prediction accuracy exceeding 90%. When the predicted temperature approaches or reaches the phase change threshold (32℃), the system responds rapidly, driving the phase change material in the composite phase change core to change from solid to liquid, absorbing a large amount of heat and effectively controlling the temperature difference in the local area within 5℃, preventing excessive temperature from damaging the equipment and concrete structure. Conversely, when the temperature drops below 30℃, the phase change material solidifies from liquid to solid, releasing the previously absorbed heat and maintaining the temperature stability of the concrete matrix. The entire response process is rapid, with a delay time of no more than 5 minutes. Compared with traditional temperature control technology, this greatly shortens the temperature control lag time and significantly improves the timeliness and effectiveness of the temperature control system. To target the spatial distribution of the predicted temperature field, a localized precise temperature control accuracy of ±0.5℃ is achieved through differentiated voltages (1-5V), deeply integrating the temperature field prediction structure with the phase change driving strategy. During the forward phase change, a +3V pulse voltage is applied to the silicon carbide nanofibers to trigger the Joule heating effect of the CNTs network, driving the phase change material to melt and absorb heat (latent heat 210J / g). During the reverse phase change, a -3V voltage is applied in conjunction with a semiconductor cooling chip to activate the solidification and release heat. The piezoelectric ceramic element generates electricity through the vibration of the pump station, outputting an AC pulse signal (frequency 10-100Hz, peak voltage 0.1-2V). This signal is then converted to DC 3.3V by a rectifier and voltage regulator circuit (such as the LTC3588 chip) and stored in a supercapacitor (10F / 5.5V) to provide basic power for the entire system. The 3.3V is then boosted to an adjustable voltage of 1-5V by the edge computing module equipped in the pump station combined with a DC-DC boost circuit (such as the TPS61088). Finally, the output voltage is dynamically adjusted according to the LSTM prediction results. For example, a 3V / 10kHz square wave is output during a forward phase transition, and a -3V DC is output during a reverse phase transition (TEC driven). The semiconductor cooling chip (TEC1-12706) actively cools the material, accelerating the solidification and exothermic reaction of the phase change material.

[0024] One application example shows that after the system has been running for a period of time in a fire pump station in a city, the temperature difference between the inside and outside of the concrete has always been kept within 5°C by monitoring data through temperature sensors installed at different locations. This effectively avoids thermal stress cracks caused by excessive temperature differences. The incidence of thermal stress cracks is reduced by 90% compared with traditional pump stations. In terms of energy consumption, according to statistics from energy consumption monitoring equipment, the energy consumption of pump stations using this intelligent temperature control system in winter is reduced by 55% compared with traditional electric heat tracing systems, and the overall energy saving throughout the year reaches 45%. At the same time, because the piezoelectric ceramic element generates electricity continuously and stably, it meets the energy consumption requirements of the entire intelligent temperature control system throughout its entire life cycle, without the need for external power supply to supplement energy. In structural strength testing, the mechanical properties of concrete structures using this system were examined. Results showed that the addition of silicon carbide nanofibers increased the compressive strength of the concrete to 65 MPa, improved tensile strength by 40%, and increased flexural strength by 30%, effectively overcoming the problem of deteriorated mechanical properties in traditional phase change concrete after the addition of phase change materials. Regarding durability, observation and testing of the concrete surface revealed that the MFI zeolite coating exhibited excellent self-healing crack capabilities, with a self-healing rate exceeding 85% within 28 days, significantly extending the structural lifespan of the fire pump station by 30% compared to traditional pump stations. Furthermore, data from air quality monitoring equipment within the pump station showed that the degradation rate of airborne pollutants reached over 90%, significantly improving the working environment inside the pump station. In summary, by integrating material innovation and intelligent algorithms, this system overcomes the limitations of traditional temperature control technology, which relies on external power supply and has a delayed response. It provides an efficient solution for temperature control and crack prevention of large-volume concrete in fire pump stations and can be widely applied to similar projects in water conservancy, industry and other fields.

[0025] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An intelligent temperature control system for concrete substrates in fire pump stations, characterized in that, It includes a composite phase change core (1) incorporated into a concrete matrix, an encapsulation layer (2), and a nanofiber layer (3). The encapsulation layer (2) is disposed on the outside of the composite phase change core (1) to form a microcapsule; The nanofiber layer (3) is distributed in a three-dimensional network on the outside of the encapsulation layer (2) to form a three-dimensional thermal conductive path (5); The three-dimensional heat conduction path (5) integrates a fiber optic grating sensor (6) for acquiring multimodal data and a piezoelectric ceramic element (7) for power supply. The model is trained by LSTM to receive multimodal data and predict temperature field changes, so as to drive the composite phase change core (1) to undergo phase transformation. The local temperature difference of the latent heat balance of phase transformation is used to realize the integrated temperature control of phase change energy storage, nano-thermal conduction and intelligent response.

2. The intelligent temperature control system for concrete substrates in fire pump stations according to claim 1, characterized in that, The composite phase change core (1) is a paraffin-fatty acid eutectic phase change material core.

3. The intelligent temperature control system for concrete substrates in fire pump stations according to claim 2, characterized in that, The encapsulation layer (2) is a uniform and dense coating layer formed by depositing boehmite solution on the surface of the composite phase change core (1).

4. The intelligent temperature control system for concrete substrates in fire pump stations according to claim 1, characterized in that, The nanofiber layer (3) consists of silicon carbide nanofibers with a diameter of 50-200 nm and an aspect ratio of 200:

1. The silicon carbide nanofibers are pre-dispersed in a polycarboxylate superplasticizer solution by ultrasonic oscillation technology to form a uniform suspension, ensuring the three-dimensional network distribution of silicon carbide nanofibers in concrete.

5. The intelligent temperature control system for concrete substrates in fire pump stations according to claim 4, characterized in that, The nanofiber layer (3) in the three-dimensional network densification part of silicon carbide nanofibers is distributed in a gradient along the principal stress direction and is suitable for the part with a bending radius ≤1.5m.

6. The intelligent temperature control system for concrete substrates in fire pump stations according to claim 1, characterized in that, The nanofiber layer (3) is externally coated with an MFI zeolite molecular sieve coating (4) for catalytic degradation of pollutants and humidity regulation.

7. The intelligent temperature control system for concrete substrates in fire pump stations according to claim 1, characterized in that, Both the fiber optic grating sensor (6) and the piezoelectric ceramic element (7) are arrayed. The fiber optic grating sensor (6) monitors the temperature of the stress concentration zone inside the concrete matrix in real time. Combined with the piezoelectric ceramic element (7), the structure vibration generates electricity to form an intelligent monitoring network.

8. The intelligent temperature control system for concrete substrates in fire pump stations according to claim 7, characterized in that, The fiber optic grating sensor (6) is divided into two parts. The first part is embedded in the interlayer of the nanofiber layer (3) in a spiral shape with a spacing of 10-20 mm, covering more than 80% of the volume of the phase change material. The second part is distributed on the surface of the encapsulation layer (2) in both axial and circumferential dimensions. The axial grating spacing is 50 mm, and one set is arranged every 120° in the circumferential direction to realize the three-dimensional reconstruction of the temperature field gradient.

9. The intelligent temperature control system for concrete substrates in fire pump stations according to claim 7, characterized in that, The piezoelectric ceramic element (7) is stacked in multiple layers and distributed in a honeycomb array.

10. A method for intelligent temperature control of concrete substrate in fire pump stations, employing any one of the intelligent temperature control systems claimed in claims 1-9, characterized in that, The specific steps are as follows: S1 uses the sol-gel method to encapsulate paraffin-fatty acid eutectic phase change material in a boehmite shell to form microcapsules with a particle size of 2-5 mm. S2 disperses silicon carbide nanofibers with a diameter of 50-200 nm and an aspect ratio of 200:1 in a polycarboxylate superplasticizer solution by ultrasonic oscillation to form a uniform suspension; S3 uses sulfoaluminate low-heat cement mixed with 30% fly ash, and incorporates 5% phase change microcapsules in the core area and 2% nanofiber suspension in the middle layer. The surface is sprayed with a 5-10μm MFI zeolite molecular sieve coating to form a "heat absorption-heat conduction-humidity regulation" structure. S4 pre-embedded fiber optic grating sensors and piezoelectric ceramic elements are mainly arranged in stress concentration areas. The piezoelectric ceramic elements generate power through vibration. S5 uses an LSTM neural network to predict the peak temperature field over 1 hour, driving the phase change material to absorb / release heat and utilizing the latent heat balance of the local temperature difference.

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