International Journal of Heat and Fluid Flow最新文献_第10页

Pseudo three-dimensional topology optimization of chip heat sinks with various inlet–outlet arrangements 具有不同进出口排列的芯片散热器的伪三维拓扑优化

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-26 DOI: 10.1016/j.ijheatfluidflow.2024.109670

Jin Huang , Wanting Li , Bohao Chen , Kai Jiao , Qiuwang Wang , Cunlu Zhao

Topology optimization (TO) represents a significant advancement in heat sink design for microelectronic chips. Although two-dimensional (2D) TO is favored for its simplicity and lower computational cost, it lacks the accuracy of three-dimensional (3D) TO, omitting certain processes inherent to 3D models. This paper introduces a novel pseudo 3D TO model, which integrates a 2D thermo-fluid design layer with a 2D conductive base plate layer, specifically optimized for chip heat sink designs. Employing the variable density method, we establish a mathematical description of the pseudo 3D TO, incorporating governing equations for flow dynamics and temperature variations in both layers. A distinctive feature of this model is its consideration of thermal coupling in the dimension typically neglected by standard 2D TO models. We applied the pseudo 3D TO model to optimize heat sink structures across various inlet and outlet configurations, followed by rigorous analyses to compare flow and heat transfer performances. These comparisons offer critical insights into the advantages and trade-offs of each configuration. Ultimately, a 3D heat sink was reconstructed from the pseudo 3D optimization results, and a detailed numerical experiment was conducted to assess its thermal performance under realistic conditions, thereby validating the efficacy and reliability of the pseudo 3D TO model. The findings underscore the model’s potential in achieving efficient and practical heat sink designs, balancing accuracy and computational efficiency.

拓扑优化（TO）是微电子芯片散热器设计的一大进步。虽然二维拓扑优化因其简单性和较低的计算成本而受到青睐，但它缺乏三维拓扑优化的精确性，省略了三维模型固有的某些过程。本文介绍了一种新型伪三维 TO 模型，该模型集成了二维热流体设计层和二维导电底板层，专门针对芯片散热器设计进行了优化。利用变密度方法，我们建立了伪三维 TO 的数学描述，其中包含两层中流动动力学和温度变化的控制方程。该模型的一个显著特点是考虑了通常被标准二维 TO 模型忽略的维度上的热耦合。我们应用伪三维 TO 模型来优化各种入口和出口配置的散热器结构，然后进行严格的分析，比较流动和传热性能。这些比较为了解每种配置的优势和权衡提供了重要依据。最后，根据伪三维优化结果重建了三维散热器，并进行了详细的数值实验，以评估其在实际条件下的热性能，从而验证了伪三维 TO 模型的有效性和可靠性。研究结果强调了该模型在实现高效实用的散热器设计方面的潜力，同时兼顾了精确性和计算效率。

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引用次数: 0

Preparation and characterization of modified steel slag-based composite phase change materials 改性钢渣基复合相变材料的制备与表征

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-23 DOI: 10.1016/j.ijheatfluidflow.2024.109666

Chenhao Yang , Zekai Zhang , Haowen Yu , Nian Xu , Zucun Rui , Huaqiang Chu

In order to promote the resource utilization in steel slag and reduce the environmental hazards caused by steel slag, a steel slag-based composite phase change material was prepared in this experiment. Steel slag had a porous structure with good structural stability, which could be used to prepare composite phase change materials and applied in fields such as thermal energy storage and waste heat recovery. To enhance the adsorption capacity of steel slag on phase change materials, the impact of acid or alkali modifiers on steel slag was meticulously examined. The investigation revealed that the pore structure of the modified steel slag was markedly enhanced, accompanied by a notable improvement in adsorption capacity. Among the results, the adsorption rate of the acid washed modified steel slag for paraffin reached 35 %, with the phase change temperature and latent heat of phase change being 53 °C and 60 J/g. Acid washing had a significant impact on the pore structure of the steel slag, with the adsorption rate of the acid washed modified steel slag for paraffin being approximately twice that of the unmodified steel slag.

为了促进钢渣的资源化利用，减少钢渣对环境造成的危害，本实验制备了一种基于钢渣的复合相变材料。钢渣具有多孔结构，结构稳定性好，可用于制备复合相变材料，并应用于热能储存和余热回收等领域。为了提高钢渣对相变材料的吸附能力，实验细致研究了酸碱改性剂对钢渣的影响。研究发现，改性钢渣的孔隙结构明显改善，同时吸附能力也显著提高。其中，酸洗改性钢渣对石蜡的吸附率达到 35%，相变温度和相变潜热分别为 53 °C 和 60 J/g。酸洗对钢渣的孔隙结构有显著影响，酸洗改性钢渣对石蜡的吸附率约为未改性钢渣的两倍。

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引用次数: 0

Hydrothermal performance enhancement of heat sink using low flow-drag twisted blade-like fins 利用低流动阻力的扭曲叶片式散热片提高散热器的水热性能

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-22 DOI: 10.1016/j.ijheatfluidflow.2024.109669

Shoutong Ji, Cairang Huadan, Pan Qi, Zhenwei Liu, Ping Li

To prevent power equipment from breaking down due to overheating, an innovative design of twisted blade-like fins for heat sinks is proposed to enhance heat transfer efficiency and minimize pressure drop. The effects of the twist angle and different NACA airfoil cross-section of fins on the flow and heat transfer characteristics are investigated using numerical simulation methods over a Reynolds number range of 8548 to 34194. Comparing the twisted blade-like fins with cylindrical fins, the relative Nusselt number is 1.067–1.397, the relative friction coefficient is 0.528–1.339, and the hydrothermal performance factor (HTPF) is 1.155–1.552. The results demonstrate that the novel twisted blade-like fins substantially outperform cylindrical fins in terms of comprehensive thermal performance. Furthermore, the optimal design in the study is compared with the best design in similar studies, and the results show that the optimal twisted blade-like fins exhibit better advantages in drag reduction performance and HTPF. When Reynolds number is 34194, the twisted blade-like fins provide the highest HTPF of 1.552. The twisted blade-like fins stimulate spanwise and normalwise secondary flow, promoting fluid exchange between the wall and the channel core, thereby enhancing the heat transfer performance of the heat sink. Increasing the twist angle will improve heat transfer efficiency but increase pressure drop. Different cross-section shape can have different effects, and using NACA0009 airfoil cross-section yields better results in most cases. The twisted blade-like fins are effective in the field of heat transfer enhancement with low flow resistance of streamlined structure and strong heat transfer effect of secondary flow, greatly improving the comprehensive thermal performance of the heat sink.

为防止电力设备因过热而发生故障，提出了一种用于散热器的扭曲叶片状翅片的创新设计，以提高传热效率并最大限度地减少压降。在雷诺数为 8548 到 34194 的范围内，采用数值模拟方法研究了翅片的扭曲角度和不同 NACA 翼面截面对流动和传热特性的影响。将扭曲叶片状翅片与圆柱形翅片进行比较，发现相对努塞尔特数为 1.067-1.397，相对摩擦系数为 0.528-1.339，水热性能系数（HTPF）为 1.155-1.552。结果表明，新型扭曲叶片状翅片的综合热性能大大优于圆柱形翅片。此外，研究中的最优设计与类似研究中的最佳设计进行了比较，结果表明，最优的扭曲叶片状翅片在减阻性能和 HTPF 方面表现出更好的优势。当雷诺数为 34194 时，扭曲叶片状翅片的 HTPF 最高，达到 1.552。扭曲的叶片状鳍片可刺激跨向和法向二次流，促进壁面与通道芯之间的流体交换，从而提高散热器的传热性能。增大扭曲角度会提高传热效率，但会增加压降。不同的截面形状会产生不同的效果，在大多数情况下，使用 NACA0009 机翼截面会产生更好的效果。扭曲的叶片状翅片在热传导增强领域效果显著，流线型结构流阻小，二次流传热效果强，大大提高了散热器的综合热性能。

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引用次数: 0

Thermal-hydrodynamic analysis for internally interrupted-finned tubes: Experimental, numerical and performance study 内部间断翅片管的热流体力学分析：实验、数值和性能研究

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-22 DOI: 10.1016/j.ijheatfluidflow.2024.109665

O.H. Salem, Ahmed Hegazy, K. Yousef

The characteristics of fluid flow and heat transfer in an internally interrupted-finned tube were studied, experimentally and numerically, and a performance evaluation study was conducted in the present research. The numerical results were validated with the current experimental data as well as other published data, with a maximum deviation of 8.93 %. The effect of different key parameters like fin height, number of fin-rows, fin thickness and number of fins in each row on the thermal-hydrodynamic performance was explored. This study reveals that increasing both fin height and number of fin-rows raises the heat transfer coefficient and friction factor values, but fin thickness negligibly affects the performance. Notably, the average heat transfer coefficient value rises by 25.03 % if the fin height to diameter ratio is increased from 0.1786 to 0.4018, and by 21.4 % if the number of fins is increased from 2 to 6, compared to finless tubes under a mass flow rate of 0.39 kg/s, for three number of fins per row. Compared to the continuously finned tubes, the interrupted-finned tubes have higher heat transfer coefficient values if the interruption length is equal to or less than the fin length, while these values are reduced below that of the continuously finned if the interruption length is larger than the fin length. Clearly, when the interruption length is 3 times the fin length, the heat transfer coefficient value of the continuously finned tube is higher than that of the interrupted-finned one by 3.1 %, while the heat transfer coefficient value of the interrupted-finned tube is higher than that of the continuously finned one by 13.59 %, when the interruption length is reduced to one-third of the fin length. It is recommended using the interrupted-finned tubes over the smooth ones if the amount of mass flow rate flowing through both tubes is the same, but the use of interrupted-finned tubes is not recommended as opposed to smooth ones if both tubes are subjected to the same pressure drop across them.

本研究通过实验和数值方法研究了内部间断翅片管中的流体流动和传热特性，并进行了性能评估研究。数值结果与当前的实验数据以及其他已公布的数据进行了验证，最大偏差为 8.93%。研究还探讨了不同关键参数，如鳍片高度、鳍片排数、鳍片厚度和每排鳍片数量对热流体力学性能的影响。研究表明，增加翅片高度和翅片排数可提高传热系数和摩擦因数值，但翅片厚度对性能的影响微乎其微。值得注意的是，在质量流量为 0.39 千克/秒、每排翅片数量为 3 的条件下，如果翅片高度与直径之比从 0.1786 增加到 0.4018，平均传热系数值将比无翅片管提高 25.03%；如果翅片数量从 2 增加到 6，平均传热系数值将提高 21.4%。与连续翅片管相比，当间断长度等于或小于翅片长度时，间断翅片管的传热系数值较高，而当间断长度大于翅片长度时，传热系数值则低于连续翅片管。显然，当间断长度是翅片长度的 3 倍时，连续翅片管的传热系数值比间断翅片管的传热系数值高 3.1%，而当间断长度减小到翅片长度的三分之一时，间断翅片管的传热系数值比连续翅片管的传热系数值高 13.59%。如果流过两根管子的质量流量相同，建议使用间断翅片管，而不是光滑翅片管；但如果两根管子上的压降相同，则不建议使用间断翅片管，而不是光滑翅片管。

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引用次数: 0

Modulation of the local mass and heat transfer of turbulent double-diffusive convection under stable thermal stratifications 稳定热分层下湍流双扩散对流的局部质量和热量传递调制

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-21 DOI: 10.1016/j.ijheatfluidflow.2024.109636

S. Kenjereš , R. Roovers

We report on numerical studies of bounded double-diffusive turbulent convection, which involves the combined effects of concentration/solutal and thermal buoyancy forces. Our study focuses on an intermediate range of the characteristic non-dimensional numbers, specifically

1 0^{7} \leq {Ra}_{c} \leq 1 0^{9}

, and

0 \leq {Ra}_{θ} \leq 1 0^{6}

. We use fixed values for the concentration and temperature Prandtl numbers (i.e.

\Pr_{c} = 700

,

\Pr_{θ}

= 7), which approximately correspond to seawater properties. We apply wall-resolved Large Eddy Simulations (LES) and compare the obtained results with available Direct Numerical Simulations (DNS) in the literature. Our findings show an overall good agreement in predicting the global wall mass and heat transfer coefficients, achieved with significantly reduced computational costs. Furthermore, the local mass and heat transfer distributions reveal a high sensitivity to the strength of the vertically imposed stable thermal stratification. Finally, we present the vertical profiles of the long-term time-averaged first and second moments.

我们报告了对有界双扩散湍流对流的数值研究，这种对流涉及浓度/溶解力和热浮力的综合影响。我们的研究侧重于特征非维数的中间范围，特别是 107≤Rac≤109 和 0≤Raθ≤106。我们使用浓度和温度普朗特尔数的固定值（即 Prc=700, Prθ = 7），这大致符合海水的特性。我们应用了壁面分辨大涡流模拟（LES），并将获得的结果与文献中的直接数值模拟（DNS）进行了比较。我们的研究结果表明，在预测全局壁面质量和传热系数方面，两者总体上非常一致，而且计算成本大大降低。此外，局部质量和传热分布显示出对垂直施加的稳定热分层强度的高度敏感性。最后，我们展示了长期时间平均第一矩和第二矩的垂直剖面。

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引用次数: 0

Visual boiling experimental research based on lateral liquid supply structure 基于横向供液结构的可视沸腾实验研究

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-21 DOI: 10.1016/j.ijheatfluidflow.2024.109664

Fei Li, Guodong Xia, Ran Li

The high heat transfer coefficient and critical heat flux density of thin liquid film boiling provide new ideas for enhancing boiling heat transfer, but the bottom-up liquid supply method limits its further application and development. This study is based on the experimental research results of previous researchers and adds lateral liquid supply while maintaining a lower liquid level. And thin liquid film boiling experiments were conducted on the surface of silicon under low subcooling conditions (subcooling degree: 5 K). The obtained curves were compared with the results of smooth copper surface in pool boiling experiments. Among them, thin liquid film boiling exhibits excellent HTC and higher CHF (12.26 W/cm²·K and 191.63 W/cm², respectively). Then, the bubble behavior and flow characteristics of thin liquid film boiling bubbles were visualized and the heat transfer mechanism was analyzed. The experimental results indicate that the lateral liquid supply boiling structure designed in this study has great potential for application.

薄液膜沸腾的高传热系数和临界热通量密度为增强沸腾传热提供了新思路，但自下而上的供液方式限制了其进一步应用和发展。本研究在前人实验研究成果的基础上，在保持较低液面的前提下，增加了横向供液。并在低过冷度条件下（过冷度：5 K）在硅表面进行了薄液膜沸腾实验。所得曲线与光滑铜表面的池沸腾实验结果进行了比较。其中，薄液膜沸腾表现出优异的 HTC 和更高的 CHF（分别为 12.26 W/cm2-K 和 191.63 W/cm2）。然后，观察了薄液膜沸腾气泡的行为和流动特性，并分析了其传热机理。实验结果表明，本研究设计的横向供液沸腾结构具有很大的应用潜力。

引用次数: 0

Influence of inclined magnetic field on mixed convective cross flow across a cylinder with uniform heat flux condition 倾斜磁场对均匀热通量条件下圆柱体上混合对流横流的影响

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-21 DOI: 10.1016/j.ijheatfluidflow.2024.109648

Rupam Saha, B. Hema Sundar Raju

This numerical study delves into the interplay between inclined magnetohydrodynamic flow and mixed convective heat transfer in a cylindrical geometry under uniform heat flux condition. The study employs a quasi-static model, where the fluid is flowing in a cross-stream regime, satisfies the Boussinesq approximation. A higher-order finite difference scheme is adopted to discretize the non-linear Navier–Stokes and energy equations, followed by a stable pseudo-time iterative technique. This study reveals that a lower Richardson number and interaction parameter are sufficient to induce vortex shedding under positive magnetic angles that can not be achieved in case of aligned magnetic field. Increasing the strength of magnetic field tends to restore the symmetric flow structure from the buoyancy-driven asymmetric one, contingent upon the magnetohydrodynamic flow orientations. The coefficients of viscous and pressure drag, average Nusselt number become non-monotonic for the aligned magnetic field, whereas it becomes strictly monotonic for other positive magnetic inclination angles at each Richardson number. Interestingly, increasing magnetic inclination angle allows to augment the total drag coefficient and overall heat transfer drastically. Critical interaction parameter is determined for average Nusselt number at various Richardson and Reynolds numbers under aligned magnetic field. The heat transfer is significantly more enhanced under uniform heat flux condition compared to constant wall temperature condition. The enhanced heat transfer achieved through magnetic field integration and modified thermal conditions has significant potential for applications such as electronic cooling, solar collectors, material processing, and more.

本数值研究深入探讨了在均匀热通量条件下，圆柱几何体中倾斜磁流体与混合对流传热之间的相互作用。研究采用了准静态模型，流体在横流状态下流动，满足布森斯克近似。采用高阶有限差分方案对非线性纳维-斯托克斯方程和能量方程进行离散计算，然后采用稳定的伪时间迭代技术。研究表明，在正磁场角下，较低的理查森数和相互作用参数足以诱发涡旋脱落，而在对齐磁场情况下则无法实现。磁场强度的增加往往会从浮力驱动的非对称流动结构恢复到对称流动结构，这取决于磁流体力学流动方向。对齐磁场的粘性和压力阻力系数、平均努塞尔特数变得不单调，而在每个理查森数下，其他正磁倾角的粘性和压力阻力系数、平均努塞尔特数变得严格单调。有趣的是，增加磁倾角可以大幅提高总阻力系数和总传热。在对齐磁场下，确定了不同理查德森数和雷诺数下平均努塞尔特数的临界相互作用参数。与恒定壁温条件相比，均匀热通量条件下的传热明显更强。通过磁场集成和修改热条件实现的强化传热在电子冷却、太阳能集热器、材料加工等应用中具有巨大潜力。

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引用次数: 0

Study on flow non-uniformity and design of tapered manifold inlet structure of manifold microchannels 分流微通道流量不均匀性研究与锥形分流入口结构设计

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-19 DOI: 10.1016/j.ijheatfluidflow.2024.109645

Yuan-Sheng Lin , Kai Chen , Han-Bing Ke , Yong-Hui Xie

Effective cooling of electronic equipment in the integrated control system is critical. Manifold microchannel (MMC) liquid cooling technology has many advantages, but the non-uniform distribution of coolant limits its heat transfer performance. This study analyzed the non-uniformity of MMC heat sinks through numerical simulations. A tapered manifold inlet structure was proposed to improve flow uniformity. Additionally, since numerical simulations are computationally intensive, a temperature prediction method for MMC heat sink based on a reduced-order model was proposed. The results show that the tapered manifold inlet structure can improve the flow uniformity, and the improvement is more obvious with the increase of the taper angle. The average relative error (RE) and the average maximum absolute error (MAE) of the reduced-order model are 0.00406 % and 0.78 K respectively, which indicates that the reduced-order model can predict the temperature distribution of MMC heat sink quickly and accurately.

有效冷却集成控制系统中的电子设备至关重要。歧管微通道（MMC）液体冷却技术有很多优点，但冷却剂的不均匀分布限制了它的传热性能。本研究通过数值模拟分析了 MMC 散热器的不均匀性。研究提出了一种锥形歧管入口结构，以改善流动的均匀性。此外，由于数值模拟的计算量很大，因此提出了一种基于降阶模型的 MMC 散热器温度预测方法。结果表明，锥形分流板入口结构可以改善流动均匀性，而且随着锥角的增大，改善效果更加明显。减阶模型的平均相对误差（RE）和平均最大绝对误差（MAE）分别为 0.00406 % 和 0.78 K，表明减阶模型可以快速准确地预测 MMC 散热器的温度分布。

引用次数: 0

Experimental study on dynamic flow and heat transfer performance of silicon-based microchannel under variable thermal load 变热负荷下硅基微通道的动态流动和传热性能实验研究

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-18 DOI: 10.1016/j.ijheatfluidflow.2024.109663

Meiyong Li , Yunyi Wang , Ding Wang , Jiayu Wang , Limei Shen

The issue of high power density in chips has become one of the bottlenecks restricting the improvement of chip performance. Silicon-based microchannel heat sinks (Si-MCHS) can guide the cooling fluid close to the chip junction, significantly enhancing the cooling capability. Due to the rapid changes in chip power consumption, understanding the flow and heat transfer performance of Si-MCHS, especially their dynamic heat transfer performance, is crucial. This paper introduces the fabrication of Si-MCHS and experimentally tests its static and dynamic performance. The microchannels can handle a maximum thermal flux of 71.3 W/cm2. It was found that the temperature response process of Si-MCHS mirrors that of a first-order system’s step response or zero-input response. Upon a sudden change in power consumption, the thermal response can reach 90 % of the steady-state temperature difference (ΔT) within 4 s and 50 % ΔT within 1 s. Increasing the pump speed significantly reduces the response time, while different power step changes have minimal impact on the response time. Consequently, we have formulated a graded flow rate control strategy based on the flow and heat transfer performance of Si-MCHS, which achieves effective flow rate control.

芯片的高功率密度问题已成为制约芯片性能提高的瓶颈之一。硅基微通道散热器（Si-MCHS）可以引导冷却液靠近芯片结点，显著提高冷却能力。由于芯片功耗的快速变化，了解 Si-MCHS 的流动和传热性能，尤其是其动态传热性能至关重要。本文介绍了 Si-MCHS 的制作方法，并对其静态和动态性能进行了实验测试。微通道可处理的最大热通量为 71.3 W/cm2。研究发现，Si-MCHS 的温度响应过程反映了一阶系统的阶跃响应或零输入响应。增加泵速可显著缩短响应时间，而不同功率阶跃变化对响应时间的影响微乎其微。因此，我们根据 Si-MCHS 的流量和传热性能制定了分级流量控制策略，从而实现了有效的流量控制。

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引用次数: 0

A MOPSO-based design optimization on molten salt steam generator forced circulation system under off-design conditions 非设计条件下基于 MOPSO 的熔盐蒸汽发生器强制循环系统优化设计

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2024-11-17 DOI: 10.1016/j.ijheatfluidflow.2024.109659

Jiaming Tian, Biao Li, Bo Ren, Yueshe Wang

The concentrating solar power (CSP) technologies have been demonstrated their effectiveness in providing ancillary services for peak regulation in power systems with high penetration of renewable energy. Investigating control mechanisms of a forced circulation mode applied in the steam generator, which a shell-and-tube heat exchanger, in the CSP plant is imperative for swift adaptation to its off-design operating conditions. This study aims to develop a predictive model for the hydrodynamics of a molten salt steam generator in a forced circulation mode, integrating heat transfer and phase change through the lumped parameter method. Additionally, a solution approach is proposed based on multi-objective particle swarm optimization (MOPSO) to achieve thermal-economic optimization designs of the steam generator under varying off-design conditions. Optimization analyses are conducted separately for the constant load and the off-design conditions, considering variables such as molten salt flow rate, steam-water circulation flow rate, number of baffles, and tube diameter of the heat exchanger. The results reveal that during the prolonged operation at low evaporation rates, employing an evaporator with more baffles and a larger tube diameter of 20 mm leads to favorable outcomes. Conversely, meticulous design considerations are imperative when planning for sustained high evaporation rates due to the significant impact of the number of baffles on both efficiency and economic costs. At a load of 215 t/h, the adding of two baffles results in an approximate increase of $20 million in operational costs by nearly and an improvement in efficiency by 0.01. Additionally, a fitting formula is provided to offer recommendations on optimal mass flow rates that maximize effectiveness and minimize economic costs for varying evaporation demands under off-design conditions, thereby assisting engineers in optimizing peak regulation operations.

聚光太阳能发电（CSP）技术在为可再生能源渗透率较高的电力系统提供调峰辅助服务方面的有效性已得到证实。为了迅速适应非设计运行条件，研究 CSP 电站蒸汽发生器（管壳式热交换器）强制循环模式的控制机制势在必行。本研究旨在为强制循环模式下的熔盐蒸汽发生器建立流体力学预测模型，通过集合参数法整合传热和相变。此外，还提出了一种基于多目标粒子群优化（MOPSO）的求解方法，以实现蒸汽发生器在不同非设计条件下的热经济优化设计。考虑到熔盐流速、蒸汽-水循环流速、挡板数量和换热器管径等变量，分别对恒定负荷和非设计工况进行了优化分析。结果表明，在低蒸发率的长时间运行中，采用具有更多挡板和更大管径（20 毫米）的蒸发器会带来有利的结果。相反，由于挡板数量对效率和经济成本都有显著影响，因此在规划持续高蒸发率时，必须进行细致的设计考虑。在负荷为 215 吨/小时的情况下，增加两块挡板可使运营成本增加近 2000 万美元，效率提高 0.01。此外，还提供了一个拟合公式，针对非设计条件下的不同蒸发需求，提出了最佳质量流量的建议，以实现效率最大化和经济成本最小化，从而帮助工程师优化调峰操作。

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引用次数: 0