Case Studies in Thermal Engineering最新文献

Thermal performance of shell-and-tube polymeric hollow fiber heat exchangers as oil coolers 壳管式聚合物中空纤维热交换器作为油冷却器的热性能

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-22 DOI: 10.1016/j.csite.2024.105329

Motor oil must be appropriately treated in motors, and aluminum plate heat exchangers are used to cool it. An aluminum heat exchanger is an additional part of the oil treatment module, which increases its size and weight. Two compact plastic shell-and-tube heat exchangers were tested alongside with aluminum heat exchanger to evaluate the efficiency of the plastic cooling core inside the oil module. A total of 63 experimental points were tested on three heat exchangers with good thermal balance (discrepancy of about 1,8 %), and the data were used to evaluate the heat transfer coefficients. While plastic unit PA11 showed the heat outputs exceeding the heat output of the aluminum plate unit by about 7 %, the pressure drops were about ten times higher. The unit PEEK showed good performance and pressure drops on the oil side, but the heat transfer was limited by a small heat transfer surface. Analysis of thermal resistances confirmed that the thermal resistance between the wall and the oil is dominant due to the oil's low thermal conductivity and high viscosity. The results showed that optimization of the fiber structures is needed, aiming to increase the oil flow around the fiber structures.

电机中的机油必须经过适当处理，铝板热交换器用于冷却机油。铝热交换器是油处理模块的一个额外部件，会增加模块的尺寸和重量。为了评估油模块内塑料冷却核心的效率，我们同时测试了两个紧凑型塑料壳管式热交换器和铝热交换器。在热平衡良好（差异约为 1.8%）的三个热交换器上共测试了 63 个实验点，并利用这些数据评估了传热系数。塑料装置 PA11 的热量输出比铝板装置的热量输出高出约 7%，但压降却高出约 10 倍。PEEK 单元在油侧表现出良好的性能和压降，但由于传热表面较小，传热受到限制。热阻分析表明，由于油的导热率低、粘度高，壁和油之间的热阻占主导地位。结果表明，需要对纤维结构进行优化，以增加纤维结构周围的油流。

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引用次数: 0

Thermal runaway evolution of a 4S4P lithium-ion battery pack induced by both overcharging and unilateral preheating 过充电和单侧预热诱发 4S4P 锂离子电池组的热失控演化

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-22 DOI: 10.1016/j.csite.2024.105324

To clarify the thermal runaway characteristics of lithium-ion battery pack, this study has established a thermal runaway experimental platform based on actual power battery pack. A 4 in series and 4 in parallel battery pack was assembled using 86 Ah lithium iron phosphate batteries, and the experiment of thermal runaway induced by overcharging and unilateral preheating was carried out. The behavior and characteristics including the temperature change characteristics of each cell, the heat generated and transfer paths during thermal runaway propagation, the voltage changes of each serial module and the total voltage, flame evolution behavior, gas generation characteristics, debris, and mass loss were investigated. The research results show that module 1 was the first to experience thermal runaway due to preheating. The redistributed current caused the batteries in the remaining modules to rapidly generate heat. Subsequently, the heat transfer from module 1 triggered thermal runaway in modules 2, 3, and 4 in sequence. The entire flame combustion process lasted for 38 min, with the maximum temperature reaching 937.1 °C, resulting in thermal runaway in all batteries. The sequence of thermal runaway has been clarified, with the flame generated by the ignition of the battery casing, connecting tabs, and combustible gases emitted from the batteries serving as the primary paths for heat transfer and thermal radiation. The experimental results provide valuable insights into the thermal engineering issues of large-scale lithium-ion battery pack.

为了弄清锂离子电池组的热失控特性，本研究建立了一个基于实际动力电池组的热失控实验平台。使用 86 Ah 磷酸铁锂电池组装了 4 串 4 并电池组，并进行了过充电和单侧预热引起的热失控实验。实验研究了热失控过程中各电池单元的温度变化特征、热失控传播过程中产生的热量和传递路径、各串联模块的电压变化和总电压变化、火焰演化行为、气体产生特征、碎片和质量损失等行为和特征。研究结果表明，由于预热，模块 1 最先出现热失控。重新分配的电流导致其余模块中的电池迅速发热。随后，模块 1 的热传递依次引发了模块 2、3 和 4 的热失控。整个火焰燃烧过程持续了 38 分钟，最高温度达到 937.1 °C，导致所有电池出现热失控。热失控的顺序已经明确，电池外壳、连接片点燃产生的火焰以及电池释放的可燃气体是热传导和热辐射的主要途径。实验结果为大型锂离子电池组的热工程问题提供了宝贵的见解。

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引用次数: 0

Multi-criteria study and machine learning optimization of a novel heat integration for combined electricity, heat, and hydrogen production: Application of biogas-fueled S-Graz plant and biogas steam reforming 多标准研究和机器学习优化新型热能集成系统，实现电力、热能和氢气的联合生产：以沼气为燃料的 S-Graz 工厂和沼气蒸汽转化的应用

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-22 DOI: 10.1016/j.csite.2024.105323

The current research introduces an environmentally friendly heat design method by employing biogas fuel, aiming to yield electricity, hydrogen, and heating load simultaneously. The proposed arrangement consists of a biogas-powered S-Graz plant and a biogas steam reforming cycle. Although methane-fueled S-Graz plants for multigeneration purposes have been studied in previous studies, research on employing biogas fuel to launch a S-Graz plant and integrating a biogas steam reforming cycle with such a plant has yet to be examined. The model is simulated using the engineering equation solver software, and the study includes thermodynamic, exergoeconomic, and sustainability assessments to show the potential of the suggested configuration. By conducting a sensitivity study, a machine learning optimization method within MATLAB is implemented to exhibit the final optimal solution for the proposed arrangement. This optimization uses artificial neural networks and a non-dominated sorting genetic algorithm-II algorithm in a triple-objective framework based on energy efficiency, sustainability index, and products’ specific cost. The optimization demonstrates that the mentioned objectives reach optimal values of 58.26 %, 4.56, and 15.56 $/GJ, respectively. Also, the optimal net output power and hydrogen production rate equal 5746 kW and 1.45 m³/s, respectively. Besides, the process determines the optimal exergy efficiency, total net present value, and payback period as 52.70 %, 50.3 M$, and 8.96 years, respectively. The total investment cost rate for this system also is found to be 219.8 $/h.

目前的研究通过使用沼气燃料引入了一种环境友好型供热设计方法，旨在同时产生电力、氢气和供热负荷。建议的安排包括一个沼气动力 S-Graz 发电厂和一个沼气蒸汽转化循环。虽然以前的研究已对以甲烷为燃料的 S-Graz 发电厂进行过研究，但关于使用沼气燃料启动 S-Graz 发电厂以及将沼气蒸汽转化循环与此类发电厂结合起来的研究还没有进行过研究。该模型使用工程方程求解软件进行模拟，研究包括热力学、能源经济和可持续性评估，以显示建议配置的潜力。通过进行敏感性研究，在 MATLAB 中实施了一种机器学习优化方法，以展示建议配置的最终最优解。该优化方法在基于能源效率、可持续性指数和产品具体成本的三重目标框架中使用了人工神经网络和非支配排序遗传算法-II 算法。优化结果表明，上述目标的最优值分别为 58.26%、4.56 和 15.56 美元/GJ。同时，最佳净输出功率和氢气生产率分别为 5746 kW 和 1.45 m3/s。此外，该流程确定的最佳放能效率、总净现值和投资回收期分别为 52.70%、50.3 百万美元和 8.96 年。该系统的总投资成本率为 219.8 美元/小时。

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引用次数: 0

Impact of collector aspect ratio on the energy and exergy efficiency of a louvered fin solar air heater 集热器长宽比对百叶窗翅片太阳能空气加热器能效和放能效的影响

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-22 DOI: 10.1016/j.csite.2024.105312

Solar air heaters have huge applications in renewable energy utilization segments concerning the issues of space heating, drying, and ventilation systems. Performance prediction of such systems largely depends upon the design of the collector itself. The present study has highlighted the influence of various aspect ratios of the collector on the thermal and exergy performance of louvered finned solar or air heaters. In this context, an experimental analysis has been carried out to compare the performance of LFSAH with conventional PSAH. These results show that an increase in aspect ratios enhances thermal efficiencies of heat transfer and the systems. An aspect ratio of 4:1 showed the maximum thermal efficiencies as 81.63 % for LFSAH and 68.13 % for PSAH. On the other hand, at larger mass flow rates, the exergetic efficiency of LFSAH becomes lower owing to the larger friction and exergy losses and sometimes even lower than that of PSAH. The novelties of the present study are in emphasizing the importance of aspect ratio in optimizing solar air heater design and providing relevant insight for better energy use.

太阳能空气加热器在空间加热、干燥和通风系统等可再生能源利用领域有着广泛的应用。此类系统的性能预测很大程度上取决于集热器本身的设计。本研究强调了集热器的各种长宽比对百叶窗翅片太阳能空气加热器的热性能和放能性能的影响。在此背景下，进行了实验分析，以比较百叶窗翅片太阳能热水器和传统 PSAH 的性能。结果表明，纵横比的增加提高了传热和系统的热效率。长宽比为 4:1 时，LFSAH 的最大热效率为 81.63%，PSAH 为 68.13%。另一方面，在较大的质量流量下，由于摩擦和放能损失较大，LFSAH 的能效变得较低，有时甚至低于 PSAH。本研究的创新之处在于强调了高宽比在优化太阳能空气加热器设计中的重要性，并为更好地利用能源提供了相关启示。

引用次数: 0

Thermodynamic evaluation of a Ca-Cu looping post-combustion CO2 capture system integrated with thermochemical recuperation based on steam methane reforming 基于蒸汽甲烷重整的钙-铜循环燃烧后二氧化碳捕集系统与热化学回收的热力学评估

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-22 DOI: 10.1016/j.csite.2024.105327

The calcium looping integrated with the chemical looping combustion (CaL-CLC) process is an efficient and cost-effective CO₂ capture technology that avoids the energy-intensive air separation unit in the calcium looping (CaL) process. However, in these CaL-CLC and CaL system integration schemes, the carbonation heat is utilized for steam generation, resulting a significant temperature difference and considerable irreversible loss. To prevent temperature mismatch, this paper proposes a novel Ca-Cu looping post-combustion CO₂ capture method with thermochemical recuperation based on steam methane reforming. Additionally, a novel system integrated with turbine exhaust heat recovery is introduced to effectively reduce carbon emissions from flue gas. Results show that the proposed system has superior performance compared to the reference system based on the Ca-Cu looping method. The specific primary energy consumption for CO₂ avoidance decreased from 2.40 MJ_LHV/kg CO₂ in the reference system to 2.02 MJ_LHV/kg CO₂. Exergy analysis indicates that a total of 3.0 % reduction in exergy destruction can be achieved in chemical reaction processes and heat recovery processes, contributing to the superior performance of the proposed system. Furthermore, the effects of key operating parameters indicate that cascaded turbine exhaust recovery is essential for improving the thermodynamic efficiency of the proposed system. Overall, recovering the mid-temperature carbonation heat via thermochemical regeneration and integrating with exhaust heat recovery contribute to reducing SPECCA, thus providing a promising low-energy-consumption alternative for CO₂ capture.

钙循环与化学循环燃烧（CaL-CLC）工艺是一种高效且经济的二氧化碳捕集技术，它避免了钙循环（CaL）工艺中的高能耗空气分离装置。然而，在这些 CaL-CLC 和 CaL 系统集成方案中，碳化热被用于产生蒸汽，从而导致显著的温差和相当大的不可逆损失。为防止温度失配，本文提出了一种基于蒸汽甲烷重整的热化学回收的新型 Ca-Cu 循环燃烧后二氧化碳捕集方法。此外，还介绍了一种与汽轮机排气热回收相结合的新型系统，以有效减少烟气中的碳排放。结果表明，与基于 Ca-Cu 循环方法的参考系统相比，拟议系统具有更优越的性能。避免产生二氧化碳的一次能源消耗量从参考系统的 2.40 MJLHV/kg CO2 降至 2.02 MJLHV/kg CO2。放能分析表明，在化学反应过程和热回收过程中，放能破坏可总共减少 3.0%，这也是拟议系统性能优越的原因之一。此外，关键运行参数的影响表明，级联涡轮机排气回收对提高拟议系统的热力学效率至关重要。总之，通过热化学再生回收中温碳化热并与废气热回收相结合，有助于降低 SPECCA，从而为二氧化碳捕集提供了一种前景广阔的低能耗替代方案。

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引用次数: 0

A high-performance all-day vertical thermoelectric generator based on a double-sided reflective structure 基于双面反射结构的高性能全天候垂直热电发生器

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-22 DOI: 10.1016/j.csite.2024.105333

Harvesting environmental energy sources is crucial for achieving renewable energy generation and net-zero emissions. However, ensuring uninterrupted electricity generation from environmental energy sources remains challenging. In this study, we present a simple, compact, and expandable all-day vertical passive thermoelectric generator (V-TEG) with a double-sided reflective structure that simultaneously harnesses solar and space cold energy. Outdoor experimental measurements, combined with finite element simulation analysis, revealed that the optimal angles of the solar reflector relative to the TEG range from 30° to 50°. Additionally, the TEG placed in the north–south orientation was found to enhance its daytime performance. The use of low-cost black paint combined with the solar reflector achieved equivalent spectral selectivity, effectively minimizing the infrared heat loss of the hot end of the TEG. During a 48-h outdoor test, the V-TEG achieved an average daytime power of 112.00 mW/m² and a peak of 363.42 mW/m². Comparative experiments demonstrated that the V-TEG outperformed horizontally placed TEG during the daytime. Furthermore, scaling the system by connecting three TEGs in series significantly increased the daily power output. This compact V- TEG system offers a promising solution for long-term power generation in low-power sensors and off-grid communities, supporting renewable energy and carbon neutrality goals.

收集环境能源对于实现可再生能源发电和净零排放至关重要。然而，确保从环境能源中不间断发电仍具有挑战性。在这项研究中，我们提出了一种简单、紧凑、可扩展的全天候垂直无源热电发电机（V-TEG），其双面反射结构可同时利用太阳能和空间冷能。户外实验测量结合有限元模拟分析表明，太阳能反射器相对于 TEG 的最佳角度为 30° 至 50°。此外，研究还发现，将 TEG 放置在南北方向可提高其日间性能。使用低成本的黑色涂料与太阳能反射器相结合，实现了同等的光谱选择性，有效地减少了 TEG 热端红外热损。在 48 小时的室外测试中，V-TEG 的日间平均功率为 112.00 mW/m2，峰值为 363.42 mW/m2。对比实验表明，V-TEG 在白天的表现优于水平放置的 TEG。此外，通过串联三个 TEG 来扩大系统规模，可显著提高日输出功率。这种结构紧凑的 V- TEG 系统为低功率传感器和离网社区的长期发电提供了一种前景广阔的解决方案，有助于实现可再生能源和碳中和目标。

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引用次数: 0

Research on the process of heat transfer between mobile variable temperature heat source and thermoacoustic plate 移动变温热源与热声板之间的传热过程研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-22 DOI: 10.1016/j.csite.2024.105311

The purpose of this paper is to analyze the effects of several easy-to-operate parameters (operating frequency, plate stack length, plate stack position, and amplitude) on the refrigeration performance, to explore the optimization path of thermoacoustic refrigerator, and to provide a design basis for further cost reductions. The heat transfer process between the air mass and the plate was investigated as an object, and the physical and mathematical models of the heat transfer process were established. The gas microcluster moving heat and plate stack temperature difference were taken as the response. Operating frequency, plate position, plate length and gas vibration displacement amplitude were the design factors. The change relationship of the system response under the interaction of factors was analyzed by using the central composite experimental design and the response surface method, and experimental verification was carried out. The results show that the deviation of the predicted model from the experimental data is less than 5.9 % when the operating frequency is in the range of 0 Hz–12 Hz, and that the location of the plate stack is 0.45 from the pressure belly point of the sound field, where the heat of the air mass transfer is the largest.

本文旨在分析几个易于操作的参数（工作频率、板堆长度、板堆位置和振幅）对制冷性能的影响，探索热声冰箱的优化路径，为进一步降低成本提供设计依据。以气团和板之间的传热过程为研究对象，建立了传热过程的物理和数学模型。以气体微团移动热量和板堆温差作为响应。工作频率、板位置、板长度和气体振动位移幅度为设计因素。采用中心复合实验设计和响应面法分析了各因素相互作用下系统响应的变化关系，并进行了实验验证。结果表明，当工作频率在 0 Hz-12 Hz 范围内时，预测模型与实验数据的偏差小于 5.9%，板堆位置距声场压力腹点 0.45 处，空气传质热量最大。

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引用次数: 0

Thermal resistance capacity model for transient simulation of capillary-box heat exchangers 用于毛细管箱式热交换器瞬态模拟的热阻容量模型

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-21 DOI: 10.1016/j.csite.2024.105321

In this paper, a novel simplified hybrid model is developed to simulate the transient thermal behaviors of capillary-box heat exchangers (CBHEs) buried in the seabed, serving as the front-end heat exchangers in seawater source heat pump system (SWHPs). The thermal resistance and capacity (TRC) approach is applied for derivation of the governing equations inside and outside the heat exchangers. Also, an analytical solution is integrated to model heat transfer in the seabed base. The effects of seawater seepage on the thermal performance of CBHEs are taken into account in the present model. The state-space representation is used to solve the governing equations. The model is verified against experimental data, achieving very good agreement with the mean bias error (MBE) of 7.2 %. A comparison with a three-dimensional computational fluid dynamic (CFD) model indicates that the TRC model's maximum relative error and MBE are 0.7 % and 2.0 % lower than those of the CFD model. Additionally, the ratio of the time required by the CFD and TRC models for a 31-day run was 138. These results demonstrate that the TRC model is sufficiently accurate and fast in the thermal simulation of CBHEs. Furthermore, the thermal properties of CBHEs are examined using the present model. The model in this study provides practical implications for heat transfer analysis and design improvement of CBHEs utilized in SWHPs.

本文开发了一种新型简化混合模型，用于模拟作为海水源热泵系统（SWHPs）前端热交换器的海底毛细管盒式热交换器（CBHEs）的瞬态热行为。热阻和热容量（TRC）方法用于推导热交换器内外的控制方程。此外，还集成了一个分析解决方案来模拟海底基底的传热。本模型考虑了海水渗入对 CBHE 热性能的影响。采用状态空间表示法来求解控制方程。根据实验数据对模型进行了验证，结果非常吻合，平均偏差误差 (MBE) 为 7.2%。与三维计算流体动力学（CFD）模型的比较表明，TRC 模型的最大相对误差和 MBE 分别比 CFD 模型低 0.7 % 和 2.0 %。此外，CFD 模型和 TRC 模型运行 31 天所需时间之比为 138。这些结果表明，TRC 模型在 CBHE 的热模拟中具有足够的准确性和快速性。此外，本模型还对 CBHE 的热特性进行了研究。本研究中的模型为传热分析和改进西南热电厂 CBHE 的设计提供了实际意义。

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引用次数: 0

Experimental analysis of the influence of PCM on the thermal behavior of lightweight buildings in different natural environments 不同自然环境下 PCM 对轻质建筑热行为影响的实验分析

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-21 DOI: 10.1016/j.csite.2024.105320

Phase-change materials (PCM) can effectively improve the thermal performance of lightweight buildings, but their heat storage and release capacity are highly dependent on the heat exchange between the wall surface and the ambient environments. However, the current research mostly focuses on numerical simulation in a specific climate environment, and the effectiveness of PCM on the thermal regulation of lightweight buildings under a long-period natural environment is insufficient. Therefore, two experimental rooms (with and without PCM) of the same size were built and conducted in this paper to compare the changing rules of wall surface temperature, heat flux, and indoor temperature in different seasons without mechanical equipment. The results show that: (1) The effect of PCM on the thermal performance of lightweight buildings is highly correlated with seasons, and its contribution efficiency varies in different seasons; (2) The attenuation rate of the internal surface temperature in different seasons can be reduced by 18.08%–42.90 %, the delay time can be improved to 2.67–4 h compared with the reference wall; (3) PCM can effectively inhibit the fluctuation and rise of indoor temperature, which can reduce the maximum indoor temperature by 4.9–12.0 °C, increase the minimum temperature by 1.1–2.8 °C, and the thermal comfort hours added by 2–5 h; (4) Lightweight buildings incorporating PCM can saves 18.69 % and 49.63 % for the peak cooling in summer and transition seasons, and 15.9 % for the heating in winter. The research results can provide the theoretical basis and experimental support for the efficient application of PCM in lightweight buildings.

相变材料（PCM）能有效改善轻质建筑的热工性能，但其蓄热和放热能力与墙体表面与周围环境的热交换有很大关系。然而，目前的研究多集中于特定气候环境下的数值模拟，对长周期自然环境下 PCM 对轻质建筑热调节的有效性研究不足。因此，本文建造了两个相同大小的实验房间（有 PCM 和无 PCM），在没有机械设备的情况下，比较了不同季节墙面温度、热通量和室内温度的变化规律。结果表明(1) PCM 对轻质建筑热工性能的影响与季节高度相关，其贡献效率在不同季节有所不同；(2) 与参考墙体相比，PCM 在不同季节的内表面温度衰减率可降低 18.08%-42.90 %，延迟时间可提高到 2.67-4 h；（3）PCM 能有效抑制室内温度的波动和升高，可使室内最高温度降低 4.9-12.0 ℃，最低温度升高 1.1-2.8 ℃，热舒适时间增加 2-5 h；（4）采用 PCM 的轻质建筑在夏季和过渡季节的峰值制冷量可分别节省 18.69 % 和 49.63 %，冬季采暖量可节省 15.9 %。这些研究成果为在轻质建筑中有效应用 PCM 提供了理论依据和实验支持。

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引用次数: 0

Numerical investigation on thermal performance of three configurations of solar thermal collector integrated with metal hydride 对集成了金属氢化物的三种太阳能集热器配置的热性能进行数值研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-21 DOI: 10.1016/j.csite.2024.105314

This study investigates the optimal configuration of a Metal Hydride-based Solar Thermal Collector (MH-STC) by developing a transient 3D mathematical model to simulate three distinct configurations: C1, C2, and C3. These configurations differ in the placement of water pipes within the metal hydride bed C1 features pipes in the top region, C2 in the core zone, and C3 at the bottom. The performance of these configurations was rigorously compared based on hydrogen charge state, outlet water temperature, useful energy output, and thermal efficiency across varying water flow rates. Results reveal that configuration C1 achieves superior thermal performance during daytime operation, producing outlet temperatures up to 10 °C higher than the other configurations. Conversely, configuration C3 excels at nighttime heating, delivering water temperatures approximately 11.5 °C higher than C1. Furthermore, the analysis indicates that hydrogen desorption pressure significantly impacts outlet water temperature; for instance, increasing the pressure from 2.41 bar to 6 bar enhances the average outlet temperature of the C3 design by about 20 °C during the day and reduces it by approximately 15 °C at night. These findings highlight the critical need for optimizing solar collector designs to effectively meet the thermal demands of both daytime and nighttime applications.

本研究通过建立一个瞬态三维数学模型来模拟三种不同的配置，从而研究基于金属水化物的太阳能集热器（MH-STC）的最佳配置：C1、C2 和 C3。这些配置的不同之处在于水管在金属氢化物床中的位置，C1 在顶部区域，C2 在核心区域，C3 在底部。根据氢荷状态、出口水温、有用能量输出和不同水流量下的热效率，对这些配置的性能进行了严格比较。结果表明，配置 C1 在白天运行时具有卓越的热性能，其出水温度比其他配置高出 10 °C。相反，配置 C3 在夜间加热时表现出色，出水温度比 C1 高出约 11.5 °C。此外，分析表明，氢解吸压力对出水温度有显著影响；例如，将压力从 2.41 巴提高到 6 巴，C3 设计的平均出水温度在白天会提高约 20 °C，而在夜间则会降低约 15 °C。这些发现凸显了优化太阳能集热器设计以有效满足白天和夜间应用的热需求的迫切需要。

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引用次数: 0