Applied Thermal Engineering最新文献_第3页

Optimized control strategy for transcritical CO2 heat pump systems under wide temperature conditions 宽温度条件下跨临界CO2热泵系统的优化控制策略

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.130040

Guangman Li , Yabin Guo , Dingbiao Wang , Xinxin Liu , Guanghui Wang , Yuduo Li

Transcritical CO₂ heat pumps (TCHPs) are regarded as an efficient and low-carbon solution for heating and hot water supply; however, their performance is highly dependent on appropriate control strategies under wide variations in ambient and water temperatures. In this study, a numerical investigation of a TCHP system operating under the original control strategy was first conducted for ambient temperatures ranging from −25 °C to 35 °C and outlet water temperatures from 30 °C to 70 °C. Based on the analysis, an optimal discharge pressure library control strategy considering segmented outlet water temperatures and multiple practical constraints (OPL-SWMC) is proposed. By optimizing the water tank configuration, the control strategies for cyclic and direct heating modes are unified, which simplifies system operation and control implementation. The effectiveness of the proposed OPL-SWMC strategy is further evaluated through a comparative study between fuzzy PID and conventional PID controllers. The results indicate that the OPL-SWMC strategy achieves a maximum coefficient of performance (COP) of 3.15, representing a 22.0% improvement compared with the original cyclic heating mode. In addition, the fuzzy PID controller significantly shortens the settling time of the discharge pressure to its optimal setpoint. Compared with the conventional PID controller, the settling time is reduced by 31.0%, 22.3%, and 30.2% at ambient temperatures of −25 °C, 15 °C, and 35 °C, respectively. Overall, the proposed OPL-SWMC strategy demonstrates robust operational stability and improved dynamic performance, providing a practical and effective control solution for TCHP systems operating under wide temperature conditions.

跨临界二氧化碳热泵（TCHPs）被认为是一种高效、低碳的供暖和热水供应解决方案；然而，它们的性能高度依赖于环境温度和水温的广泛变化下的适当控制策略。在本研究中，首先对在原始控制策略下运行的TCHP系统进行了数值研究，环境温度范围为- 25°C至35°C，出水温度范围为30°C至70°C。在此基础上，提出了一种考虑分段出水温度和多重实际约束的最优排放压力库控制策略（OPL-SWMC）。通过优化水箱配置，实现循环加热和直接加热控制策略的统一，简化了系统运行和控制实施。通过模糊PID与传统PID控制器的对比研究，进一步评价了所提出的OPL-SWMC策略的有效性。结果表明，OPL-SWMC策略的最大性能系数（COP）为3.15，比原循环加热模式提高22.0%。此外，模糊PID控制器显著缩短了排气压力稳定至最优设定值的时间。与传统PID控制器相比，在环境温度为- 25℃、15℃和35℃时，沉降时间分别缩短了31.0%、22.3%和30.2%。总体而言，所提出的OPL-SWMC策略具有强大的运行稳定性和改进的动态性能，为在宽温度条件下运行的TCHP系统提供了实用有效的控制解决方案。

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引用次数: 0

Hygrothermal transfer mechanism and airflow distribution optimization design of fully indoor substations 全室内变电站湿热传递机理及气流分布优化设计

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.130032

Yaxin Shi , Di Wu , Haolin Lian , Chuanhao Zhao , Zhijian Liu , Shicong Zhang , Xinyan Yang

Fully indoor substations reduce the impact of severe climatic conditions such as wind, frost, rain, snow, and dust on the operation of electrical equipment. However, under the coupling effect of their unique structural characteristics and outdoor meteorological conditions, the phenomenon of “hygrothermal accumulation” is becoming increasingly prominent, and hygrothermal issues have become a key challenge threatening the safe and stable operation of the power grid. This paper adopts a method combining field measurements and numerical simulation to investigate the hygrothermal environment status and airflow distribution schemes for the capacitor room of a 110 kV fully indoor substation. The innovation of this study lies in revealing the thermal-humidity coupled transfer mechanism in the distinctive “small space, strong heat source” environment of a fully indoor substation's capacitor room and in establishing a computational model for the heat generation of electrical equipment. To address the issues of “airflow short-circuiting” and “airflow guidance”, optimization schemes involving the extension of exhaust outlets and the modification of louver structures are proposed. The results indicate that extending the outlet to above the disconnector rack via a duct can effectively resolve the problem of “airflow short-circuiting”. The optimal louver air inlet structure scheme is “louver aspect ratio of 0.8 and louver inclination angle of -45°”, which can reduce the average temperature in the capacitor operating area by 23.8% and increase the average air velocity by 84.4%. The research results provide a theoretical basis and engineering reference for the ventilation design of similar substations.

全室内变电站减少了风、霜、雨、雪、尘等恶劣气候条件对电气设备运行的影响。然而，在其独特的结构特征与室外气象条件的耦合作用下，“湿热积累”现象日益突出，湿热问题已成为威胁电网安全稳定运行的关键挑战。本文采用现场实测与数值模拟相结合的方法，对某110 kV全室内变电所电容器室的湿热环境状况及气流分布方案进行了研究。本研究的创新之处在于揭示了全室内变电所电容室独特的“小空间、强热源”环境下的湿热耦合传递机理，建立了电气设备产热计算模型。针对“气流短路”和“气流引导”问题，提出了延长排气口和修改百叶结构的优化方案。结果表明，通过风道将出口延伸至隔离架上方，可有效解决“气流短路”问题。最优百叶进气结构方案为“百叶长径比为0.8，百叶倾角为-45°”，可使电容器工作区域平均温度降低23.8%，平均风速提高84.4%。研究结果为类似变电站的通风设计提供了理论依据和工程参考。

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引用次数: 0

Numerical simulation study on the mechanism and characteristics of gas quenching granulation of molten steel slag 钢渣气淬造粒机理及特性的数值模拟研究

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.129904

Jiayu Zhu , Shuzhong Wang , Jun Zhao , Zhiyong Bai , Ruibin Xue , Qingyuan Wang , Zizhao Wang

Driven by global carbon neutrality goals, the waste heat recovery and resource utilization of molten steel slag is a key pathway for the steel industry to achieve energy conservation and emission reduction. As the most promising key technology, gas quenching granulation still faces industrial challenges such as unclear breakup mechanisms and difficulties in controlling particle size and cooling rate. This paper innovatively establishes a 3D gas quenching model that, for the first time, integrates liquid film breakup with subsequent particle flight and cooling by coupling the VOF to DPM with the energy transport equation and considering the temperature-dependent viscosity, thereby enabling more realistic simulation of the dynamic granulation and heat transfer characteristics of steel slag. The study reveals the granulation mechanism wherein the liquid film destabilizes due to the gas liquid velocity difference and ultimately granulates into droplets through perforation breakup and ligament breakup. The granulation characteristics are jointly determined by the gas-to-slag kinetic energy ratio, melt resistance, and impingement geometry. Notably, increasing the vertical distance between outlets is far more detrimental to granulation than increasing the horizontal distance, and CO₂ is a superior quenching medium to air, while adding water vapor deteriorates granulation quality. Furthermore, particle temperature drop is proportional to flight velocity, while both are inversely proportional to particle size, with smaller particles achieving higher flight velocities and faster cooling. Finally, an empirical correlation for predicting the Sauter Mean Diameter is established through dimensional analysis, and an optimal process window is proposed, providing a theoretical reference for the quantitative prediction of the gas quenching granulation process and the synergistic optimization of process parameters.

在全球碳中和目标的推动下，钢渣余热回收与资源化利用是钢铁行业实现节能减排的重要途径。气淬造粒作为最具发展前景的关键技术，在工业上仍面临破碎机理不清、粒度控制和冷却速度控制困难等挑战。本文创新性地建立了三维气淬模型，通过将VOF与DPM耦合，结合能量输运方程，并考虑温度依赖的粘度，首次将液膜破碎与后续颗粒的飞行和冷却结合起来，从而更真实地模拟钢渣的动态造粒和传热特性。研究揭示了液膜因气液速度差而失稳，最终通过穿孔破裂和韧带破裂成粒成滴的制粒机理。制粒特性由气渣动能比、熔体阻力和撞击几何形状共同决定。值得注意的是，增加出口之间的垂直距离远比增加水平距离对造粒的危害更大，并且CO2是优于空气的淬火介质，而加入水蒸气会使造粒质量恶化。此外，颗粒温度下降与飞行速度成正比，而两者与颗粒尺寸成反比，颗粒越小，飞行速度越高，冷却速度越快。最后，通过量纲分析建立了预测Sauter平均直径的经验相关性，并提出了最优工艺窗口，为气淬造粒工艺的定量预测和工艺参数的协同优化提供了理论参考。

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引用次数: 0

Multi-objective optimization of porous structure with non-uniform pore distribution for transpiration cooling with phase change 相变蒸腾冷却非均匀孔隙结构的多目标优化

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.130027

Yatong Zhao, Fei He, Taolue Liu

Performance prediction and structure optimization are key issues for transpiration cooling with liquid-vapor phase change in aerospace engineering applications. Based on accurate coupled simulation of hypersonic airflow and transpiration cooling process, this study establishes an efficient data-driven collaborative optimization framework to perform multi-objective optimization of the pore layout in the transpiring cooling structure to achieve higher cooling efficiency, lower temperature non-uniformity and lower injection pressure. Firstly, the influencing mechanism of porous structural parameters on cooling performance is systematically analyzed. The results indicate that an appropriate permeability gradient enhances stagnation point cooling and overall temperature uniformity, and the permeability gradient significantly affects the internal two-phase flow pressure distribution inside the porous structure. Meanwhile, the reasonable segment length design can further optimize the two-phase flow path. Through multi-objective optimization, the optimal structural parameters are identified, and the superior cooling performance and enhanced flow and heat transfer mechanisms of the optimal model are revealed. The results indicate that the optimal model improves stagnation point cooling efficiency by 8.6%, reduces surface temperature non-uniformity by 22.8%, decreases the maximum pressure drop by 54.4%, and forms a thicker coolant film. This study provides new insights into the structural optimization of aerospace thermal protection.

在航空航天工程中，液-气相变蒸腾冷却的性能预测和结构优化是关键问题。基于高超声速气流与蒸腾冷却过程的精确耦合模拟，建立了高效的数据驱动协同优化框架，对蒸腾冷却结构孔隙布置进行多目标优化，以实现更高的冷却效率、更低的温度不均匀性和更低的喷射压力。首先，系统分析了多孔结构参数对冷却性能的影响机理。结果表明，适当的渗透率梯度可以提高滞止点冷却和整体温度均匀性，渗透率梯度对多孔结构内部两相流压力分布有显著影响。同时，合理的段长设计可以进一步优化两相流路。通过多目标优化，确定了最优结构参数，揭示了最优模型优越的冷却性能和强化的流动传热机理。结果表明，优化后的模型使驻点冷却效率提高8.6%，表面温度不均匀性降低22.8%，最大压降降低54.4%，冷却液膜厚度增加。该研究为航天热防护结构优化提供了新的思路。

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引用次数: 0

Efficient encapsulation of metal-based phase change materials and their direct electro-thermal conversion performance 金属基相变材料的高效封装及其直接电热转换性能

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.130043

Mingjian Xu , Xiaojie Guo , Chenwu Shi , Peihang Li , Junfeng Shen , Hao Wang , Shuyan Zhu , Deqiu Zou

Direct electro-thermal conversion integrates electric-thermal conversion materials with thermal storage materials, showing great prospects in accommodation of clean energy. Metal-based phase change materials (PCMs) with high electrical conductivity, thermal conductivity, and heat storage density, have remained underexplored due to inefficient encapsulation strategies. Herein, we report the first implementation of metal-based PCMs for electro-thermal conversion under different encapsulation strategies. Firstly, a single-layer encapsulation strategy was developed by compacting metallic Sn with carbon-based materials, forming shape-stabilized composite PCMs (SSCPCMs) with low-metal-content. To improve encapsulation efficiency and structural stability, two-stage encapsulation strategy was designed to construct high–metal-loading SSCPCMs with dual-layer structure. The inner layer contains high-content Sn and carbon-based materials, while the outer layer encapsulates it using carbon-based materials and Sn@void@SiO₂–carbon black microcapsules (MEPCMs), compared with Sn@void@SiO₂ MEPCMs. This design not only improves encapsulation efficiency but also imparts latent heat storage capability to the shell for the first time, enabling cooperative heat storage between the inner and outer layers. During sintering, partially molten Sn infiltrates the interface, forming a continuous and dense metallic bonding layer upon cooling. The SSCPCMs exhibit excellent heat storage density (294.59 J/cm³), electro-thermal conversion efficiency (95.9% at 1.8 V) and a rapid heating rate. This study provides an effective route to advance metal-based PCMs for direct electro-thermal systems, offering new opportunities for clean energy storage and sustainable thermal management.

直接电热转换将电热转换材料与蓄热材料相结合，在容纳清洁能源方面具有广阔的前景。具有高导电性、高导热性和高储热密度的金属基相变材料（PCMs）由于封装策略效率低下，一直未得到充分开发。在此，我们报告了在不同封装策略下首次实现电热转换的金属基pcm。首先，将金属锡与碳基材料压实，形成低金属含量的形状稳定复合PCMs （SSCPCMs）。为了提高封装效率和结构稳定性，设计了两阶段封装策略，构建具有双层结构的高金属负载sscpcm。与Sn@void@SiO2 mepcm相比，内层含有高含量的Sn和碳基材料，外层采用碳基材料和Sn@void@SiO2 -炭黑微胶囊（mepcm）封装。这种设计不仅提高了封装效率，而且首次赋予了外壳潜热储存能力，实现了内层和外层的协同储热。烧结过程中，部分熔融锡渗入界面，冷却后形成连续致密的金属结合层。sscpcm具有优异的储热密度（294.59 J/cm3）、1.8 V时的电热转换效率（95.9%）和快速升温速率。该研究为推进金属基pcm用于直接电热系统提供了有效途径，为清洁能源储存和可持续热管理提供了新的机会。

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引用次数: 0

Numerical study on the integration of three-dimensional n-decane/air rotating detonation combustor and supersonic turbine stage 三维正癸烷/空气旋转爆震燃烧室与超声速涡轮级集成的数值研究

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.129857

Wei Zhang , Ningbo Zhao , Xiaofeng Shao , Hongtao Zheng

The integration of rotating detonation combustors (RDCs) with supersonic turbines is of considerable interest due to its considerable potential for enhancing performance and enabling compact designs. However, the internal fluid dynamics of three-dimensional RDC-supersonic turbine systems remain insufficiently understood, which hinders efficient integration. To bridge this gap, this study conducts three-dimensional numerical simulations of this integrated system to investigate the flow field structure, turbine stage performance, and aerodynamic and thermal loads on turbine blades. It is indicated that the complex shock wave system composed of leading-edge shock waves, reflected shock waves, λ shock waves, and trailing-edge shock waves is induced due to the interaction between oblique shock waves and turbine cascade. The propagation direction of different rotating detonation waves dominates the flow deflection at the inlet of the nozzle guide vanes, and the maximum velocity angle variation in the upstream and downstream regions of the oblique shock wave reaches 27.78%. Moreover, the separation zone in the turbine cascade dynamically evolves with the circumferential propagation of rotating detonation waves. The rotating detonation inflow conditions result in a complex oscillation state where the total pressure at the rotor inlet and turbine performance parameters exhibit superposition of low-frequency and high-frequency oscillations. Compared to misaligned mode, aligned mode reduces turbine stage total pressure loss and improves stagnation isentropic efficiency. For nozzle guide vanes and rotor blades, instantaneous aerodynamic and thermal loads substantially exceed time-averaged values. These loads concentrate on guide vane surfaces contacting the oblique shock wave, while localizing primarily on pressure surfaces and leading edges of rotor blades. This study can provide useful insights for the research of rotating detonation turbine engines.

旋转爆震燃烧室（rdc）与超音速涡轮的集成由于其在提高性能和实现紧凑设计方面的巨大潜力而引起了相当大的兴趣。然而，三维rdc -超声速涡轮系统的内部流体动力学仍然不够清楚，这阻碍了高效集成。为了弥补这一空白，本研究对该集成系统进行了三维数值模拟，研究了流场结构、涡轮级性能以及涡轮叶片的气动和热负荷。研究表明，斜激波与涡轮叶栅的相互作用导致了由前缘激波、反射激波、λ激波和尾缘激波组成的复杂激波系统。不同旋转爆震波的传播方向主导了喷管导叶入口处的流动偏转，斜激波上下游区域的最大速度角变化达到27.78%。涡轮叶栅内的分离区随着旋转爆震波的周向传播而动态演化。旋转爆震流入条件导致转子进口总压和涡轮性能参数呈现低频和高频振荡叠加的复杂振荡状态。与不对准模式相比，对准模式降低了涡轮级总压损失，提高了滞止等熵效率。对于喷嘴导叶和转子叶片，瞬时气动和热负荷大大超过时间平均值。这些载荷集中在与斜激波接触的导叶表面，而主要集中在转子叶片的压力面和前缘。该研究可为旋转爆震涡轮发动机的研究提供有益的见解。

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引用次数: 0

Enhanced heat-moisture transfer and thermal mitigation of wet multistage meridian units for high temperature exhaust gas 高温废气湿式多级子午线装置增强热湿传递和热缓解

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.130021

Ya’nan Zhang , Baochao Xie , Shiqiang Chen , Fengtian Lin , Xiaodi Xing

Efficient mitigation of thermal hazards, which are caused by high-temperature exhaust gas from diesel internal combustion engines for power generation, has long been a challenge in the industry. Overcoming this technical bottleneck requires enhancing heat and moisture transfer. Furthermore, the development of optimized control equipment. In response, this study proposes wet meridian units composite technology and establishes wet multistage meridian units (W2MU) experimental system. On this system, saline with the salinity of 38.5 ± 0.1 g/L and the temperature of 26 ± 0.5 °C was prepared. Under the total water-to-gas ratio of 3:1, five-stage uniform spray experiment (each stage with a water-gas ratio of 0.6:1) were conducted to obtain variations of exhaust gas temperature across six measurement points. Experimental results show that the overall cooling efficiency of W2MU reached 82.03%, with the first stage contributing 87.16% of total temperature drop. The Number of Transfer Units (NTU), cited from classic heat and moisture transfer equations, failed to predict actual cooling efficiency. Under the condition of high-temperature, the failure was between numerical predictions and experimental data, which reached up to 86.8%. The classic equations are unable to affect liquid film and its dynamic renewal on heat and moisture transfer process. To quantify those effects, a correlation between inlet temperature and liquid film renewal frequency is established, and NTU calculation is revised accordingly. After the correction term of NTU was determined by numerical iteration, it is proposed that a heat and moisture transfer enhancement calculation model coupled with Le-NTU. This proposition of W2MU guides for the management of diesel engine exhaust cooling and optimizes airflow waste heat recovery in industry application.

长期以来，有效缓解由柴油内燃机发电产生的高温废气造成的热危害一直是行业面临的挑战。克服这一技术瓶颈需要加强热量和水分的传递。此外，优化控制设备的开发。为此，本研究提出湿经络单元复合技术，建立湿多级经络单元（W2MU）实验系统。在该体系上制备了盐度为38.5±0.1 g/L、温度为26±0.5℃的生理盐水。在总水气比为3:1的条件下，进行5级均匀喷雾实验（每级水气比为0.6:1），得到6个测点的废气温度变化情况。实验结果表明，W2MU的整体冷却效率达到82.03%，其中第一级降温贡献率为87.16%。从经典的热湿传递方程中引用的传递单位数（NTU）无法预测实际的冷却效率。在高温条件下，数值预测和实验数据之间的破坏率高达86.8%。经典方程无法影响液膜及其动态更新对热湿传递过程的影响。为了量化这些影响，建立了进口温度与液膜更新频率之间的相关性，并相应地修改了NTU计算。通过数值迭代确定NTU的修正项后，提出了一种耦合Le-NTU的热湿传递增强计算模型。W2MU的这一主张为柴油机排气冷却管理提供指导，并在工业应用中优化气流余热回收。

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引用次数: 0

Optimal coupling of solar and geothermal energy sources for driving an organic Rankine cycle 驱动有机朗肯循环的太阳能和地热能的最佳耦合

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.130036

Dimitra Gonidaki, Evangelos Bellos, Kosmas A. Kavadias, John K. Kaldellis

The present study concerns the design and simulation of a hybrid Organic Rankine cycle (ORC) powered by solar and geothermal energy. The system is designed for maximized geothermal source utilization through partial evaporation. A dynamic simulation is performed considering the climate conditions of Athens, Greece, and hexane as the working medium in the system. The hybrid ORC is evaluated for four medium-grade geothermal water temperatures, 100 °C, 120 °C, 140 °C, and 160 °C, and six solar collecting areas from 100 to 600 m² and its performance is compared with the corresponding standalone solar and geothermal systems. The results show that the hybrid system achieves higher annual electricity production across the majority of examined cases, with a maximum increase of 8.1% over the separate systems, and a lower Levelized Cost of Energy (LCOE), ranging from 0.037 €/kWh to 0.119 €/kWh. A multi-criteria analysis is also conducted to identify the optimal solar collecting area for each geothermal source by minimizing the distance to the ideal solution on a Pareto front defined by two objectives: maximum electricity production and minimum LCOE. The findings highlight that source hybridization under a careful design is a solution of high potential for the development of effective and sustainable units for electricity generation.

本研究涉及太阳能和地热能驱动的混合有机朗肯循环（ORC）的设计和模拟。该系统旨在通过部分蒸发来最大限度地利用地热资源。以希腊雅典的气候条件为条件，以己烷为工质，进行了系统的动态模拟。在100°C、120°C、140°C和160°C 4种中等地热水温度和100 ~ 600 m2 6个太阳能集热面积下，对混合ORC进行了评价，并与独立的太阳能和地热系统进行了性能比较。结果表明，在大多数测试案例中，混合动力系统实现了更高的年发电量，与单独系统相比，最大增幅为8.1%，且平均能源成本（LCOE）较低，范围为0.037欧元/千瓦时至0.119欧元/千瓦时。还进行了多标准分析，通过最小化帕累托前沿的理想解决方案的距离来确定每个地热源的最佳太阳能收集区域，该解决方案由两个目标定义：最大发电量和最小LCOE。研究结果强调，在精心设计下的源杂交是开发有效和可持续发电装置的高潜力解决方案。

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引用次数: 0

Fabric-based all-in-one evaporator for high-performance solar desalination: An analytic hierarchy process evaluation 基于织物的高性能太阳能脱盐一体化蒸发器：层次分析法评价

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.129998

Fangzhou Liu , Xiangjun Liu , Qianqian Liu , Cheng Shao , Meng An , Jianshi Sun , Xiongfei Zhu , Chunfang Guo , Shouhang Li

Solar-driven interfacial evaporation (SDIE) is a promising technology for addressing the global freshwater shortage. Traditional evaporators in SDIE systems consist of separate components, which complicates the structure and limits large-scale applications. Here, an all-in-one evaporator is designed based on weaving technology, integrating all the functions of SDIE into a single structure. The integrated SDIE consists of foam strips and ramie yarns. The lightweight foam strips are thermally resistant and exhibit high efficiency in photothermal conversion, while ramie yarns effectively absorb seawater. The performance of the all-in-one SDIE is enhanced by optimizing the weaving structure and adjusting the diameter of the foam strips. The indoor tests show that the optimized evaporator can achieve a high evaporation rate of ∼1.56 kg/m²/h under 1 sun, with an efficiency of ∼90%. The SDIE can also generate clean water stably in outdoor experiments. Moreover, the analytic hierarchy process (AHP) was first introduced to evaluate the performance of solar evaporators. It can incorporate several performance descriptors and make the evaluation quantitative. The AHP evaluation shows that our all-in-one evaporator exhibits extraordinary holistic performance and has great potential in scalable applications.

太阳能驱动界面蒸发（SDIE）是解决全球淡水短缺的一项有前途的技术。传统的SDIE系统蒸发器由独立的部件组成，结构复杂，限制了大规模应用。在这里，我们设计了一种基于编织技术的一体机蒸发器，将SDIE的所有功能集成到一个单一的结构中。一体化SDIE由泡沫条和苎麻纱组成。轻质泡沫条耐热，光热转化效率高，苎麻纱吸收海水效果好。通过优化编织结构和调整泡沫条直径，提高了一体式SDIE的性能。室内试验表明，优化后的蒸发器在1个太阳下的蒸发速率可达~ 1.56 kg/m2/h，效率可达~ 90%。在室外实验中，SDIE也能稳定地生成干净的水。在此基础上，首次引入层次分析法（AHP）对太阳能蒸发器的性能进行评价。它可以包含多个性能描述符，并使评估量化。AHP评价表明，我们的一体机蒸发器表现出非凡的整体性能，在可扩展的应用中具有巨大的潜力。

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引用次数: 0

Comparative study on flow boiling characteristics of R1336mzz(Z) and R141b in a microchannel R1336mzz(Z)与R141b在微通道内流动沸腾特性的对比研究

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.applthermaleng.2026.129963

Zixuan Wang , Qi Peng , Xiaoqin Sun , Li Jia , Jie Li , Liaofei Yin

A numerical investigation was conducted to assess the feasibility of the environmentally friendly refrigerant R1336mzz(Z) in microchannel heat sinks as a substitute for R141b. The flow boiling characteristics were investigated at varying heat fluxes (q = 20–40 kW/m²) and mass fluxes (G = 300–600 Kg/(m²·S)) in a microchannel with 0.5 mm hydraulic diameter and 20 mm length. The transition of flow pattern from bubbly to annular was found to occur for both refrigerants. Increased heat flux significantly accelerated flow pattern evolution, whereas higher mass flux delayed the accumulation of vapor. R141b presented enhanced thermal performance under lower mass fluxes with a maximum improvement of 9.56%, whereas R1336mzz(Z) exhibited superior boiling heat transfer potential under elevated heat fluxes together with greater mass fluxes. Moreover, R1336mzz(Z) consistently showed 24.68% lower overall pressure drop than R141b and maintained more stable two-phase flow pattern at elevated heat fluxes. Furthermore, the flow boiling characteristics of both refrigerants were analyzed using dimensionless numbers such as boiling number (Bo), capillary number (Ca), and weber number (We), and the overall thermal-hydraulic performance was quantitatively evaluated by the performance evaluation criterion (PEC). This study also evaluated the performance based on commonly used correlations, revealing the effectiveness of the correlation proposed by Basu et al. in accurately predicting the heat transfer coefficients for both R141b and R1336mzz(Z), with the mean absolute errors of 12.5% and 12.03%, respectively. The results confirmed that R1336mzz(Z) exhibited superior overall thermal-hydraulic performance under medium-to-low heat fluxes and could serve as a green replacement for R141b in microchannel heat sinks.

通过数值研究，评估了环保制冷剂R1336mzz(Z)在微通道散热器中替代R141b的可行性。在水力直径为0.5 mm、长度为20 mm的微通道中，研究了不同热通量（q = 20 ~ 40 kW/m2）和质量通量（G = 300 ~ 600 Kg/(m2·S)）下的流动沸腾特性。发现两种制冷剂的流型都发生了由气泡流向环形流的转变。热通量的增加显著地加速了流型的演变，而质量通量的增加则延迟了蒸汽的积累。R141b在较低的质量通量下表现出较好的热性能，最大改善率为9.56%，而R1336mzz(Z)在较高的热通量和较大的质量通量下表现出较好的沸腾换热潜力。R1336mzz(Z)总体压降始终比R141b低24.68%，在高热通量条件下保持更稳定的两相流型。采用沸腾数（Bo）、毛细管数（Ca）和韦伯数（We）等无因次数分析了两种制冷剂的流动沸腾特性，并采用性能评价准则（PEC）对两种制冷剂的整体热工性能进行了定量评价。本研究还基于常用的相关性对性能进行了评估，结果表明Basu等人提出的相关性在准确预测R141b和R1336mzz(Z)的换热系数方面是有效的，平均绝对误差分别为12.5%和12.03%。结果表明，R1336mzz(Z)在中低热通量条件下具有优越的整体热工性能，可作为R141b微通道散热器的绿色替代品。

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引用次数: 0