International Journal of Refrigeration-revue Internationale Du Froid最新文献_第4页

Optimization of the regulation needle structure based on the flow regulation characteristic and flow loss mechanism 基于流量调节特性和流量损失机制的调节针结构优化

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-11 DOI: 10.1016/j.ijrefrig.2024.10.011

Yumeng Guo , Jingxian Zhang , Suxia Ma , Jiajie Zhang , Yaomiao Yan

The regulation needle is a key component of the variable ejector to guarantee the quality of flow control and improve ejector performance. However, the studies related to the variable ejector lack regulation needle structure optimization. In this paper, for both linear and arc-shaped nozzles, three different profiles of regulation needles: linear, elliptical, and parabolic types are optimized based on the flow regulation characteristic (FRC) and local flow loss mechanism. The calculation method of the variable nozzle FRC is established. The results show that for the arc-shaped nozzles when the bottom radius R_s of the regulation needle is 0.75 times throat radius R_t, a linear regulation needle with half-top angle α_s being 32° is recommended, which makes the FRC ideal, minimizes the entropy production and maximizes the pressure recovery ratio (PRR). For the linear nozzles equipped with the elliptical regulation needle, as the ratio of the height to the bottom radius of the regulation needle head (RHR) increases, the FRCs get closer to the ideal parabolic type, however, the entropy production increases and the PRR decreases. Therefore, the RHR is advised to be 3 for linear nozzles. The findings can serve as important guidance for optimizing variable ejector design.

调节针是可变喷射器的关键部件，可保证流量控制质量，提高喷射器性能。然而，有关可变喷射器的研究缺乏对调节针结构的优化。本文根据流量调节特性（FRC）和局部流量损失机理，对线形和弧形喷嘴的三种不同形状的调节针：线形、椭圆形和抛物线形进行了优化。建立了可变喷嘴 FRC 的计算方法。结果表明，对于弧形喷嘴，当调节针的底部半径 Rs 是喉管半径 Rt 的 0.75 倍时，推荐使用半顶角 αs 为 32° 的线性调节针，这使得 FRC 理想，熵产生最小，压力恢复比（PRR）最大。对于配备椭圆形调节针的线性喷嘴，随着调节针头高度与底部半径（RHR）之比的增加，FRC 越来越接近理想的抛物线型，但熵产生增加，PRR 下降。因此，建议线性喷嘴的 RHR 为 3。这些发现可作为优化变量喷射器设计的重要指导。

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引用次数: 0

Adaptive control for refrigeration via online identification 通过在线识别实现制冷自适应控制

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-11 DOI: 10.1016/j.ijrefrig.2024.10.004

Xiaorui Lu, Guanru Li, Chengbin Zhang

Vapor compression refrigeration systems (VCRS) occupy a crucial position in modern society and in the field of thermal sciences. However, the operation of VCRS is subjected to both external disturbances (dynamic-changing environment) and inherent system characteristics (coupling or nonlinear features), leading to issues like reduced refrigeration efficiency and significant fluctuations in cooling capacity. To address these challenges and enhance the adaptability of VCRS in dynamically changing environments, this study establishes a dynamic simulation model for VCRS based on the Switched Moving-Boundary method. The impact of external environmental disturbances on refrigeration performance is investigated, and continuous online identification methods are employed to elucidate its internal coupling characteristics and nonlinear features. The adaptive temperature control method is introduced, benefiting from the developed recursive least squares method with a forgetting factor for online identification, achieving precise model identification which facilities the real-time parameters tuning of adaptive controller. The results indicate that the hybrid paradigm of online identification and adaptive control algorithm not only effectively handles various disturbances but also reduces overshoot and IAE by 2–3 orders of magnitude compared to traditional PID controllers. Adaptive PID control maintains overshoot in the 10^–4 order of magnitude and IAE in the 10^–5 order of magnitude.

蒸汽压缩制冷系统（VCRS）在现代社会和热科学领域占据着重要地位。然而，蒸汽压缩制冷系统的运行受到外部干扰（动态变化的环境）和系统固有特性（耦合或非线性特征）的双重影响，导致制冷效率降低和制冷量大幅波动等问题。为了应对这些挑战，提高 VCRS 在动态变化环境中的适应性，本研究基于交换移动边界法建立了 VCRS 的动态模拟模型。研究了外部环境干扰对制冷性能的影响，并采用连续在线识别方法阐明了其内部耦合特性和非线性特征。利用开发的带有遗忘因子的递归最小二乘法进行在线识别，引入了自适应温度控制方法，实现了精确的模型识别，为自适应控制器的实时参数调整提供了便利。结果表明，与传统的 PID 控制器相比，在线识别和自适应控制算法的混合范例不仅能有效处理各种干扰，还能将过冲和 IAE 降低 2-3 个数量级。自适应 PID 控制将过冲保持在 10-4 数量级，IAE 保持在 10-5 数量级。

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引用次数: 0

Energy and exergy analysis of a two-stage cascade vapor compression refrigeration system with modified system configuration 采用改进系统配置的两级串联蒸汽压缩制冷系统的能量和放能分析

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-10 DOI: 10.1016/j.ijrefrig.2024.10.013

Dave Nygeil G. Patiluna , Edgar Alan A. Donasco , Noel M. Hernandez , Junil Bien A. Mamalias , Rommel R. Viña

This study proposes a modification to the two-stage cascade vapor compression refrigeration system by adding internal heat exchangers that function as subcoolers and desuperheater. The influence of each internal heat exchanger proposed on the exergy destruction rate, exergy efficiency, compressor power consumption, ECOP, and COP of the system was investigated. Additionally, various refrigerant combinations were considered as working fluids to evaluate which combination is the most suitable for the proposed system. Mathematical models based on the principles of thermodynamics were established in Engineering Equation Solver (EES), a software used for energy and exergy analysis. The results reveal that the addition of specific internal heat exchangers causes either an increase or decrease in overall system performance, depending on the type of refrigerant combination used. Consequently, there exists an optimal system configuration for each refrigerant combination. Compared with the conventional two-stage cascade refrigeration system, the optimal system configurations in the present study exhibited higher overall system performance. A maximum increase in exergy efficiency, ECOP, and COP of 7.31 %, 9.8 %, and 7.3 %, respectively, can be observed with the refrigerant combination R450A/R404A. Additionally, the results of the exergy analysis identify that the HTC compressor, condenser, LTC compressor, and cascade condenser are the primary contributors to the exergy destruction rate within the system.

本研究提出了一种对两级串联蒸汽压缩制冷系统的改进方法，即增加内部热交换器，作为过冷器和减温器。研究了所提出的每种内部热交换器对系统的放能破坏率、放能效率、压缩机功耗、ECOP 和 COP 的影响。此外，还考虑了各种制冷剂组合作为工作流体，以评估哪种组合最适合所提议的系统。根据热力学原理在工程方程求解器（EES）中建立了数学模型，该软件用于能量和放能分析。结果表明，根据所使用的制冷剂组合类型，增加特定的内部热交换器会导致系统整体性能的提高或降低。因此，每种制冷剂组合都有一个最佳系统配置。与传统的两级串联制冷系统相比，本研究中的最佳系统配置表现出更高的整体系统性能。制冷剂组合 R450A/R404A 的放能效率、ECOP 和 COP 的最大增幅分别为 7.31%、9.8% 和 7.3%。此外，放能分析结果表明，HTC 压缩机、冷凝器、LTC 压缩机和级联冷凝器是造成系统内放能破坏率的主要因素。

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引用次数: 0

Meshing pair geometry of the intersecting-axis internally geared screw compressor 相交轴内齿轮螺杆压缩机的网格对几何形状

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-10 DOI: 10.1016/j.ijrefrig.2024.10.012

Dantong Li, Zhilong He, Xiaoqian Chen, Chongzhou Sun, Kai Ma, Chuang Wang, Ziwen Xing

The Intersecting-Axis Internally Geared Screw Compressor (IISC) is an emerging advanced positive displacement machine showing the potential to greatly broaden the application of screw compressor technology. The core component of the IISC is an internally geared meshing pair with the intersecting-axis gearing, while its design methodology has not been disclosed yet. To fill the gap, this paper established the geometry model for the meshing pair and discussed the influence of its core parameters on geometric performance. First, the generation model of meshing pairs was presented, and the complete parameters set of meshing pairs was defined. The established model was verified by a meshing pair manufactured by 3D printing and CNC techniques. Next, the geometric analysis model of IISCs was established such as working volume and leakage channels, which was verified by commercial 3D software. Using the analysis model, the mesh pair parameters (rotor profile, cone angle, wrap angle, and L/D ratio) were discussed to reveal the design methodology of IISCs. Finally, the variable-pitch technology was discussed, and a novel variable-pitch method was proposed to further enhance the performance of IISCs. This paper could effectively guide the design of IISCs to further promote the development of the screw compressor technology.

相交轴内啮合螺杆压缩机（IISC）是一种新兴的先进容积式机器，显示出极大拓宽螺杆压缩机技术应用领域的潜力。IISC 的核心部件是带有相交轴齿轮的内齿轮啮合副，但其设计方法尚未公开。为填补这一空白，本文建立了啮合副的几何模型，并讨论了其核心参数对几何性能的影响。首先，介绍了啮合副的生成模型，并定义了啮合副的完整参数集。通过三维打印和数控技术制造的网格对验证了所建立的模型。接着，建立了 IISC 的几何分析模型，如工作容积和泄漏通道，并通过商用 3D 软件进行了验证。利用分析模型，讨论了网格对参数（转子轮廓、锥角、包角和长径比），从而揭示了 IISC 的设计方法。最后，讨论了变桨距技术，并提出了一种新型变桨距方法，以进一步提高 IISC 的性能。本文可有效指导 IISC 的设计，进一步推动螺杆压缩机技术的发展。

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引用次数: 0

Research progress of sorption materials in rotary desiccant wheel system{fr}Progrès de la recherche sur les matériaux de sorption dans le système de roue de dessiccation rotative 旋转干燥轮系统中吸附材料的研究进展{fr}Progrès de la recherche sur les matériaux de sorption dans le système de roue de dessiccant rotative

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-10 DOI: 10.1016/j.ijrefrig.2024.10.009

Xueping Tang , Yunfeng Wang , Jingkang Liang , Ming Li

The rotary desiccant wheel has garnered significant attention for its substantial sorption capacity and continuous regeneration mechanism. The performance of the desiccant wheel depends on two key factors: the structural parameters and the sorption material. The sorption material has a more significant impact, as optimizing this component not only enhances the sorption capacity but also lowers the regeneration temperatures, thereby mitigating the high energy consumption associated with regenerating the desiccant wheel. Such optimization further enables the integration of low-grade heat sources into the rotary desiccant wheel system. Therefore, it is essential to modify or develop stable, efficient, low-temperature regeneration desiccant wheel sorption materials. This paper reviews research on sorption materials in desiccant wheels from four perspectives: conventional, composite, nanoporous, and polymeric materials. It summarizes the latest research progress, focusing on the sorption properties, regeneration temperatures, advantages, and limitations of each material type. It concludes by analyzing the current application status and future development trends of these materials in desiccant wheels. Although some advanced materials demonstrate superior performance, practical applications remain limited. Therefore, ideal sorption materials should exhibit not only high sorption capacity but also reusability, stability, manageability, and cost-effectiveness, underscoring the need for continued research into the development of advanced materials.

旋转干燥轮因其强大的吸附能力和连续再生机制而备受关注。干燥轮的性能取决于两个关键因素：结构参数和吸附材料。吸附材料的影响更大，因为优化该部件不仅能提高吸附能力，还能降低再生温度，从而减少与干燥剂轮再生相关的高能耗。这种优化还能进一步将低品位热源整合到旋转干燥轮系统中。因此，改造或开发稳定、高效、低温再生干燥剂轮吸附材料至关重要。本文从传统材料、复合材料、纳米多孔材料和聚合物材料四个方面回顾了干燥剂轮吸附材料的研究。它总结了最新的研究进展，重点介绍了每种材料的吸附特性、再生温度、优势和局限性。最后分析了这些材料在干燥剂轮中的应用现状和未来发展趋势。尽管一些先进材料表现出卓越的性能，但实际应用仍然有限。因此，理想的吸附材料不仅要具有高吸附能力，还要具有可重复使用性、稳定性、可管理性和成本效益，这就强调了继续研究开发先进材料的必要性。

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引用次数: 0

A gray-box model for unitary air conditioners developed with symbolic regression 用符号回归法开发的单元式空调灰箱模型

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-09 DOI: 10.1016/j.ijrefrig.2024.10.008

Shahzad Yousaf , Craig R. Bradshaw , Rushikesh Kamalapurkar , Omer San

In this paper, we present the development of a gray-box model for unitary air conditioning equipment that can be trained with as little as 5 data points with higher accuracy on test data. The model utilizes the same model inputs as is typical in building energy simulation, and is accurate. While black-box models require large data sets to deliver accurate results, white-box models require higher computational and engineering efforts along with detailed knowledge of the system, and are often difficult to obtain. The model presented here addresses a hybrid solution that is a steady-state, component-based, gray-box model that requires inputs from the source and sink fluids and rated performance of the specific piece of equipment, only. The basic physics of a vapor compression cycle are captured in individual component models for the heat exchangers, compressor, and expansion valve. These components are generalized to eliminate refrigerant-side inputs. A key addition is the development of correlations for the overall heat transfer coefficient times surface area (UA) obtained from Symbolic Regression (SR). The model successfully predicts the cooling capacity, coefficient of performance (COP), and sensible heat ratio (SHR) for three state-of-the-art variable speed, split-system, air conditioning systems with capacities of 12.3(3.5), 14(4), and 17.6(5) kW(tons), achieving a mean absolute percentage error (MAPE) of less than 3.4%. These results suggest that the gray-box model can be useful in predicting the performance of similar systems in the future, which could be valuable for energy management and optimization purposes.

在本文中，我们介绍了针对单元式空调设备开发的灰盒模型，该模型只需 5 个数据点即可进行训练，并且在测试数据上具有更高的准确性。该模型使用的模型输入与建筑能耗模拟中典型的模型输入相同，并且非常准确。黑盒模型需要大量的数据集才能提供准确的结果，而白盒模型则需要更多的计算和工程设计工作以及详细的系统知识，而且通常很难获得。本文介绍的模型是一种混合解决方案，它是一种基于组件的稳态灰盒模型，只需要输入源流体和汇流体以及特定设备的额定性能。蒸汽压缩循环的基本物理原理可通过热交换器、压缩机和膨胀阀的单个组件模型来实现。对这些组件进行了概括，以消除制冷剂方面的输入。一个关键的新增功能是开发了从符号回归（SR）中获得的整体传热系数乘以表面积（UA）的相关性。该模型成功地预测了三种最先进的变速分体式空调系统的制冷量、性能系数 (COP) 和显热比 (SHR)，制冷量分别为 12.3(3.5)、14(4) 和 17.6(5) 千瓦（吨），平均绝对百分比误差 (MAPE) 小于 3.4%。这些结果表明，灰盒模型可用于预测未来类似系统的性能，这对能源管理和优化很有价值。

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引用次数: 0

Experimental performance of avocado seed oil as a bio-based phase change material for refrigeration applications 牛油果籽油作为生物基相变材料在制冷应用中的实验性能

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-09 DOI: 10.1016/j.ijrefrig.2024.10.006

Juan Francisco Nicolalde , Javier Martinez-Gómez , Víctor H. Guerrero , Andrés Chico-Proano

Bio-based phase change materials (BPCMs) derived from agro-industrial residues represent an ecofriendly alternative for refrigeration applications. In this work, a BPCM was obtained by steam extraction from avocado seed and studied as a suitable cold thermal energy storage system. First, differential scanning calorimetry was used to determine that the solid-liquid phase transition occurred from -27°C to 15°C. This temperature range is of interest for the conservation different food products. The study aimed to determine the best distribution of the material, which was stored in plastic packaging bags, and placed in an insulated polystyrene thermal container. Two configurations were evaluated: (i) four bags of 75 mL, (ii) two bags of 75 mL and one of 150 mL. The temperatures of the avocado seed oil, and of the air inside the container, were measured during 6 to 8 h. It was concluded that, despite working with the same amount of avocado seed oil (300 mL) in different experiments, there was a better performance when the same volume of material was distributed in each wall. Furthermore, the utilization of avocado seed oil allowed to maintain low temperatures, suitable for food preservation during two additional hours. In the same way, in a yogurt storage experimentation of 8 h, the utilization of the avocado oil enhanced the temperature preservation by 6°C on the phase change range from 4°C to 14°C. While compared to water, the temperature difference was evaluated showing a good performance of the BPCM and an important stability on the temperature heating rate.

从农用工业残留物中提取的生物基相变材料（BPCM）是制冷应用中的一种生态友好型替代品。在这项工作中，通过从鳄梨种子中进行蒸汽提取获得了一种 BPCM，并将其作为一种合适的冷热能储存系统进行了研究。首先，使用差示扫描量热法确定了固液相转变发生在 -27°C 至 15°C。这一温度范围对保存不同的食品具有重要意义。研究的目的是确定材料的最佳分布，材料储存在塑料包装袋中，并放置在一个隔热的聚苯乙烯保温容器中。对两种配置进行了评估：(i) 四袋 75 毫升，(ii) 两袋 75 毫升和一袋 150 毫升。结果表明，尽管在不同的实验中使用了相同数量的鳄梨籽油（300 毫升），但如果在每个壁中分配相同数量的材料，则效果更好。此外，使用鳄梨籽油可以保持低温，适合在额外的两个小时内保存食物。同样，在酸奶储存 8 小时的实验中，在 4°C 至 14°C 的相变范围内，牛油果油的使用使温度保存提高了 6°C。与水相比，温差评估显示 BPCM 性能良好，对温度升温速率具有重要的稳定性。

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引用次数: 0

Performance analysis and multi-objective optimization for an integrated air separation, power generation, refrigeration and ice thermal storage system based on the LNG cold energy utilization 基于液化天然气冷能利用的空分、发电、制冷和冰蓄冷一体化系统的性能分析和多目标优化

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-07 DOI: 10.1016/j.ijrefrig.2024.07.008

Xu Zheng , Ji Zhang , Yan Li , Zhihao Zhang , Jikai Lu , Ning Mei , Zhixiang Zhang , Han Yuan

Against the backdrop of escalating resource depletion and the urgent quest for alternative sources, liquefied natural gas (LNG) is increasingly gaining prominence as a sustainable solution, particularly in refrigeration applications. However, its underutilization results in wasted resources. To efficiently harness the released cold energy from LNG gasification, this study proposes an integrated system comprising air separation, power generation, refrigeration, and ice thermal storage. The system undergoes optimization using the non-dominated sorting genetic algorithm II (NSGA-II) to determine the optimal operating parameters. The optimized system is comprehensively analyzed from energy, exergy, economic, and environmental perspectives. Results show that the system, with a 70t/h LNG capacity, achieves an energy efficiency of 42.52% and an exergy efficiency of 48.09%. Economically, the system incurs a cost of approximately 0.0711 $/kWh and can mitigate over 1.4504*10⁷kg of CO₂ emissions. Compared to traditional LNG utilization systems, the integrated system demonstrates a 22.32% improvement in energy efficiency, a 7.69% enhancement in exergy efficiency, and a cost reduction of 0.0049 $/kWh. In summary, this technologically advanced and economically viable system offers a significant alternative to optimize LNG cold energy utilization.

在资源日益枯竭和急需寻找替代资源的背景下，液化天然气（LNG）作为一种可持续的解决方案，尤其是在制冷应用中，正日益受到重视。然而，对液化天然气的利用不足会造成资源浪费。为了有效利用液化天然气气化过程中释放的冷能，本研究提出了一个由空气分离、发电、制冷和冰蓄热组成的集成系统。该系统采用非支配排序遗传算法 II（NSGA-II）进行优化，以确定最佳运行参数。从能量、放能、经济和环境角度对优化后的系统进行了全面分析。结果表明，该系统的液化天然气产能为 70t/h，能效为 42.52%，放能效为 48.09%。在经济上，该系统的成本约为 0.0711 美元/千瓦时，可减少超过 1.4504*107 千克的二氧化碳排放量。与传统的液化天然气利用系统相比，集成系统的能效提高了 22.32%，放能效率提高了 7.69%，成本降低了 0.0049 美元/千瓦时。总之，这个技术先进、经济可行的系统为优化液化天然气冷能利用提供了一个重要的替代方案。

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引用次数: 0

Numerical investigation on scroll compressor with intermediate discharge valve for VRF annual performance promotion 带中间排气阀涡旋式压缩机的数值研究，用于提升 VRF 年度性能

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-06 DOI: 10.1016/j.ijrefrig.2024.10.005

Minghong Yang , Shuangquan Shao

Over-compression of scroll compressor in variable refrigerant flow (VRF) system is a common problem in improving system efficiency because it operates in part load conditions for most of the year. By introducing intermediate discharge valves (IDVs) to allow gas bypass from compression chamber to discharge side during compression process, the over-compression loss can be eliminated. In this study, the characteristics of compression process in IDV compressor are analysed and the effects of IDV port location and port size on compressor efficiency are discussed based on the validated high fidelity scroll compressor model. It is found that the IDVs could be able to adjust gas bypass process in different compression ratio conditions and maintain high efficiency over wider compression ratio range than that of non-IDV compressor. In addition, the VRF system model is integrated to verify the system performance improvement by IDV compressor. It is found that VRF system performance is significantly improved in cooling conditions with the IEER enhanced by 23.9 %, while limited improvement is obtained in heating conditions as the operating compression ratios are relatively higher.

可变制冷剂流量（VRF）系统中涡旋压缩机的过压缩是提高系统效率的一个常见问题，因为它一年中的大部分时间都是在部分负荷条件下运行的。通过引入中间排气阀（IDV），在压缩过程中允许气体从压缩腔旁通到排气侧，可以消除过压缩损失。本研究分析了 IDV 压缩机压缩过程的特点，并根据经过验证的高保真涡旋压缩机模型讨论了 IDV 端口位置和端口大小对压缩机效率的影响。研究发现，与非 IDV 压缩机相比，IDV 压缩机能够在不同压缩比条件下调节气体旁路过程，并在更宽的压缩比范围内保持高效率。此外，还集成了 VRF 系统模型，以验证 IDV 压缩机对系统性能的改善。结果发现，VRF 系统在制冷条件下的性能得到了显著改善，IEER 提高了 23.9%，而在制热条件下，由于运行压缩比相对较高，性能改善有限。

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引用次数: 0

Influence of irregular fiber filling on the performance of hollow fiber membrane modules for cold water production 不规则纤维填充对用于冷水生产的中空纤维膜组件性能的影响

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-05 DOI: 10.1016/j.ijrefrig.2024.09.029

Weichao Yan, Chuanjun Yang, Yu Zhang, Yahui Liu, Yilin Liu, Xin Cui, Xiangzhao Meng, Liwen Jin

The countercurrent hollow fiber membrane-based evaporative water cooler (MEWC) offers an eco-friendly and compact solution for cold water generation. This study introduces a random sequential addition algorithm to model the real-world irregular fiber filling within the MEWC. Inspired by the honeycomb structure, the developed 3-D numerical model adopts a calculation unit featuring a hexagonal prism comprising multiple fibers. Validation against experimental data reveals an average relative error of 2.81 % concerning outlet water temperature. The effects of fiber filling patterns (regular layout and random layout) on the velocity and temperature fields of the MEWC are investigated. Comparisons of outlet water temperature, cooling efficiency, consumptive electric power ratio, and heat and mass transfer resistance composition between these layouts under various operating conditions are conducted. The results indicate that the random layout fosters severe channeling effect and large flow dead zones, impairing air side heat and moisture transfer. The random layout exhibits over 15.9 % reduction in cooling efficiency and 36.3 % decrease in consumptive electric power ratio compared to the regular layout. Irregular fiber filling leads to a notable 158.6 % increase in air side heat transfer resistance and a 35.9 % rise in mass transfer resistance. Although irregular filling compromises the cooling performance, it demonstrates potential for energy savings under certain conditions. Design schemes should be carefully tailored to meet specific application requirements by considering these trade-offs.

基于逆流中空纤维膜的蒸发式水冷却器（MEWC）为冷水生产提供了一种环保、紧凑的解决方案。本研究引入了一种随机顺序添加算法，以模拟真实世界中 MEWC 内的不规则纤维填充。受蜂巢结构的启发，所开发的三维数值模型采用了一个由多根纤维组成的六角棱柱为特征的计算单元。根据实验数据进行验证后发现，出口水温的平均相对误差为 2.81%。研究了纤维填充模式（规则布局和随机布局）对 MEWC 的速度场和温度场的影响。比较了这些布局在不同运行条件下的出水温度、冷却效率、消耗功率比以及传热和传质阻力组成。结果表明，随机布局会产生严重的通道效应和较大的流动死区，影响空气侧的热量和水分传递。与常规布局相比，随机布局的冷却效率降低了 15.9%，消耗功率比降低了 36.3%。不规则纤维填充导致空气侧传热阻力显著增加 158.6%，传质阻力增加 35.9%。虽然不规则填充会影响冷却性能，但在某些条件下却具有节能潜力。应通过考虑这些权衡因素，精心定制设计方案，以满足特定的应用要求。

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引用次数: 0