Case Studies in Thermal Engineering最新文献_第3页

Optimizing cord pyramid solar distillers: A comprehensive study on square baffles, reflectors, and phase transition materials 优化绳状金字塔太阳能蒸馏器：方形挡板、反射器和相变材料综合研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-18 DOI: 10.1016/j.csite.2024.105304

Limited access to safe drinking water is a critical global issue, particularly in areas with inadequate infrastructure. Solar stills offer a promising alternative for such regions. This study investigates the influence of square baffles within a modified solar still design on its overall efficiency. Additionally, the integration of reflectors is explored to enhance both evaporation and condensation rates. Furthermore, the effectiveness of a paraffin wax phase change material (PCM) combined with silver nanoparticles is assessed within the modified still. Thermo-economic analyses are conducted to evaluate the economic feasibility of the proposed system. The findings demonstrate a significant improvement in distillation yield. The modified still with square baffles achieved a yield of 9800 mL/m².day compared to 3550 mL/m².day for the reference still, representing a 193 % increase. Moreover, incorporating the nano-PCM at an optimal configuration (25 cords) resulted in a further 265 % productivity increase for the modified still with both square baffles and reflectors. This configuration also achieved an efficiency of 63 %. Economic analysis revealed a minimal cost difference between the reference still (0.014 $/L) and the modified still with square baffles and nano-PCM (0.01 $/L). In terms of environmental impact, the modified still exhibited a lower annual CO₂ emission of 28.8 tons.

难以获得安全饮用水是一个严重的全球性问题，尤其是在基础设施不足的地区。太阳能蒸馏器为这些地区提供了一种前景广阔的替代方案。本研究探讨了改进型太阳能蒸馏器设计中方形挡板对其整体效率的影响。此外，还探讨了反射器的集成，以提高蒸发率和冷凝率。此外，还评估了石蜡相变材料（PCM）与纳米银颗粒在改进型蒸馏器中的效果。还进行了热经济分析，以评估拟议系统的经济可行性。研究结果表明，蒸馏产量有了显著提高。带方形挡板的改良蒸馏器的产量为 9800 mL/m2.天，而参考蒸馏器的产量为 3550 mL/m2.天，提高了 193%。此外，在最佳配置（25 绳）中加入纳米多孔质子交换膜后，带有方形障板和反射器的改良蒸馏器的产量进一步提高了 265%。这种配置的效率也达到了 63%。经济分析表明，参考蒸馏器（0.014 美元/升）与带方形挡板和纳米 PCM 的改良蒸馏器（0.01 美元/升）之间的成本差异极小。在环境影响方面，改进型蒸馏器的二氧化碳年排放量较低，仅为 28.8 吨。

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引用次数: 0

Simulation of behavior of solar panel in existence of nanomaterial as cooling system 模拟太阳能电池板在使用纳米材料作为冷却系统时的行为

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-18 DOI: 10.1016/j.csite.2024.105306

In current work, the productivity of a photovoltaic thermal (PVT) unit impacted by dust accumulation was improved using magnetic force. The magnetic force was implemented to a cooling duct with Y-shaped fins, while solar irradiation was included as heat sources in the equations. Dust effects were simulated by adjusting the optical properties. The addition of a thermoelectric generator (TEG) layer boosted the electrical output. The cooling fluid was a homogeneous water and iron oxide mixture. Dust accumulation led to a 9.3 % drop in thermal performance, but the use of magnetic force enhanced electrical efficiency. Higher concentrations of additives improved system performance, with a maximum gain of 15.88 % at the highest inlet velocity (V_inlet). Increasing V_inlet further improved thermal efficiency (η_th) by 10.96 %, photovoltaic efficiency (η_PV) by 1.16 %, and thermoelectric efficiency (η_TE) by 33.53 %. Moreover, the application of Lorentz force increased isothermal uniformity by approximately 5.91 %

在当前工作中，利用磁力提高了受灰尘积聚影响的光伏热（PVT）装置的生产率。磁力被应用于带有 Y 形翅片的冷却管道，而太阳辐照则作为热源被纳入方程中。通过调整光学特性来模拟灰尘的影响。热电发生器（TEG）层的加入提高了电力输出。冷却液为均匀的水和氧化铁混合物。灰尘的积累导致热性能下降了 9.3%，但磁力的使用提高了电效率。添加剂的浓度越高，系统性能越好，在最高进气速度（Vinlet）下的最大增益为 15.88%。提高 Vinlet 可进一步提高热效率（ηth）10.96%、光电效率（ηPV）1.16% 和热电效率（ηTE）33.53%。此外，洛伦兹力的应用还使等温均匀性提高了约 5.91 %。

引用次数: 0

Heat pump drying kinetics modeling and prediction for Lentinus edodes based on orthogonal experimental 基于正交实验的热泵干燥动力学建模与预测

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-18 DOI: 10.1016/j.csite.2024.105305

To accurately understand the moisture variation and drying characteristics of Lentinus edodes (L. edodes) during the drying process, the kinetics model of L. edodes with a wider application range was investigated. First, the heat pump drying kinetics model for L. edodes was fitted, verified and extended based on the orthogonal experimental data. Then, the expression of moisture ratio of L. edodes with respect to drying time, air supply temperature (AST), loading density (LD) and circulating air volume (CAV) was proposed, and interaction effects of the three key parameters on the drying time were studied based on the prediction model. The findings indicated a substantial agreement between the predicted and experimental values. The drying time could be shortened by increasing the air supply temperature and the circulating air volume or decreasing the loading density. Among these three factors, the AST had the greatest impact on drying time, followed by CAV and LD. For every 48 g/m² reduction in LD and 11.3 m³/h increase in CAV, the drying time could be reduced by 10.5–29.9 min. Similarly, increasing the AST by 1 °C and the CAV by 11.3 m³/h could decrease the drying time by 13.7–100.6 min. The research results are helpful to optimize the drying process, improve the drying efficiency, and provide guidance and references for practical production of L. edodes HPD.

为了准确了解 Lentinus edodes（L. edodes）在干燥过程中的水分变化和干燥特性，研究了适用范围更广的 L. edodes 动力学模型。首先，根据正交实验数据拟合、验证和扩展了热泵干燥 L. edodes 的动力学模型。然后，提出了菇类水分比与干燥时间、送风温度（AST）、装载密度（LD）和循环风量（CAV）的关系表达式，并根据预测模型研究了三个关键参数对干燥时间的交互影响。研究结果表明，预测值与实验值基本一致。通过提高送风温度和循环风量或降低装载密度，可以缩短干燥时间。在这三个因素中，AST 对干燥时间的影响最大，其次是 CAV 和 LD。LD 每减少 48 克/平方米，CAV 每增加 11.3 立方米/小时，干燥时间可缩短 10.5-29.9 分钟。同样，AST 增加 1 °C，CAV 增加 11.3 m3/h，干燥时间可减少 13.7-100.6 分钟。研究结果有助于优化干燥工艺，提高干燥效率，并为L. edodes HPD的实际生产提供指导和参考。

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引用次数: 0

Applied machine learning: Performance prediction of heat pipe with mesh wick 应用机器学习：网状芯热管的性能预测

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-18 DOI: 10.1016/j.csite.2024.105307

This study presents an investigation of a heat pipe with a mesh wick, utilizing machine learning (ML) techniques. The model including radial basis function interpolation (RBF), Kriging model (KRG), and the k-nearest neighborhood model (K-NN) were studied and compared. A set of training and validating populations were classified using a k-means clustering technique. The design variable included the geometric shape of heat pipe such as its diameter, the properties and percentage used of working fluid, and the temperature at the evaporator. The prediction case study included the heat transfer rate (q), and total difference temperature between evaporator and condenser section (ΔT). The prediction results found that the ΔT gave the most accurate indicator while the q is passable to applied. The Kriging model proved to be the most accurate, achieving an RMSE of 0.9896 and R² of 0.9149 for heat transfer rate prediction, and an RMSE of 0.1902 and R² of 0.9398 for total temperature difference prediction with 90 % training data. The second-best accuracy was achieved by the RBF model, with the linear, thin plate, and cubic spline kernels performing reasonably well.

本研究利用机器学习（ML）技术对带有网状芯的热管进行了研究。研究并比较了包括径向基函数插值（RBF）、克里金模型（KRG）和 k 近邻模型（K-NN）在内的模型。使用 k-means 聚类技术对一组训练群体和验证群体进行了分类。设计变量包括热管的几何形状（如直径）、工作流体的性质和使用比例以及蒸发器的温度。预测案例研究包括传热速率（q）以及蒸发器和冷凝器部分的总温差（ΔT）。预测结果表明，ΔT 是最准确的指标，而 q 则是可应用的指标。克里金模型被证明是最准确的，在 90% 的训练数据下，传热速率预测的 RMSE 为 0.9896，R2 为 0.9149；总温差预测的 RMSE 为 0.1902，R2 为 0.9398。RBF 模型的准确度次之，线性、薄板和三次样条线核的准确度也相当不错。

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引用次数: 0

Electromagnetic-thermal-mechanical performance of novel interior permanent magnet motor 新型内部永磁电机的电磁-热-机械性能

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-17 DOI: 10.1016/j.csite.2024.105259

To mitigate the challenges of magnetic leakage and iron loss in the rotor of interior permanent magnet (IPM) motors, this article proposes a novel rotor structure that eliminates the bilateral bridge, relying solely on a central bridge to maintain rotor strength. This design reduces the overall bridge width of the rotor, thereby decreasing magnetic leakage and improving torque. The novel rotor features a distinctive design that combines high silicon steel sheets and low silicon steel sheets. High silicon steel sheets are used on the rotor's surface to minimize iron loss, while low silicon steel sheets are used internally to ensure rotor strength. This design takes advantage of the high silicon steel's low iron loss while mitigating its brittleness and saturation issues. The article describes the method for producing this combined rotor. Mechanical and electromagnetic property tests are conducted on both high and low silicon steel sheets, resulting in stress-strain curves, B-H curves, and iron loss characteristics. Finally, the rotor stress is calculated. The analysis indicates that this novel motor can reduce magnetic leakage, increase torque by 7.5 %, improve efficiency by 0.18 %, decrease rotor iron loss by 36.2 %, and lower rotor temperature by 3.9 % compared to the original motor.

为了减轻内部永磁（IPM）电机转子中的漏磁和铁损问题，本文提出了一种新型转子结构，该结构取消了双边桥，仅依靠中央桥来维持转子强度。这种设计减小了转子的整体桥宽，从而减少了漏磁，提高了转矩。新型转子采用了独特的设计，将高硅钢片和低硅钢片结合在一起。转子表面使用高硅钢片，以尽量减少铁损，而内部则使用低硅钢片，以确保转子强度。这种设计利用了高硅钢的低铁损优势，同时减轻了其脆性和饱和问题。文章介绍了生产这种组合转子的方法。文章对高硅钢片和低硅钢片进行了机械和电磁特性测试，得出了应力-应变曲线、B-H 曲线和铁损特性。最后，计算了转子应力。分析表明，与原来的电机相比，这种新型电机可以减少漏磁，增加 7.5 % 的扭矩，提高 0.18 % 的效率，减少 36.2 % 的转子铁损，降低 3.9 % 的转子温度。

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引用次数: 0

Heat transfer enhancement using ternary hybrid nanofluid for cross-viscosity model with intelligent Levenberg-Marquardt neural networks approach incorporating entropy generation 利用包含熵生成的智能 Levenberg-Marquardt 神经网络方法，使用三元混合纳米流体提高交叉粘度模型的传热性能

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-16 DOI: 10.1016/j.csite.2024.105290

Thermal heat transfer analysis of trihybrid nanofluids using an intelligent Levenberg-Marquardt neural network (ANN-LMA) approach, with a focus on entropy generation, has been conducted. The flow equations were modeled in Cartesian coordinates and simplified using dimensionless variables. Partial differential equations were converted into ordinary differential equations through appropriate similarity transformations. These ordinary differential equations were then solved using the finite element method applied to a data set evaluated from (ANN-LMA) approach. This dataset can be input into MATLAB to generate predicted solutions for flow patterns. The ANN-LMA technique was employed to evaluate the efficiency of heat transfer characteristics for nanofluids in various scenarios. Incorporating carbon nanotubes (both single-wall (SWCNT) and multi-wall (MWCNT)) along with iron oxide in water, the study demonstrates their effectiveness in enhancing heat transfer. These nanofluids have broad industrial applications, such as in coolant enhancement, cancer therapy, and solar radiation management, and show promising results. This study specifically examines the flow properties of water-based CNT cross-trihybrid nanofluids over a convectively heated surface, leveraging their unique characteristics. Improvements in heat transfer are achieved through the introduction of dissipative heat, thermal radiation, and external heat sources or sinks. The performance of the computational solver was assessed using error histograms, regression analyses, and Mean Squared Error (MSE) results. The physical significance of the designed factors is graphically depicted and discussed in detail. It was found that radiative heat increases surface heat energy through substantial accumulation, thereby enhancing heat transfer properties, while dissipative heat, due to Joule dissipation and other external sources, significantly raises the fluid temperature.

采用智能 Levenberg-Marquardt 神经网络（ANN-LMA）方法对三混合纳米流体进行了传热分析，重点关注熵的产生。流动方程以直角坐标建模，并使用无量纲变量进行简化。通过适当的相似变换，将偏微分方程转换为常微分方程。然后使用有限元法对这些常微分方程进行求解，并将其应用于通过（ANN-LMA）方法评估的数据集。该数据集可输入 MATLAB，生成流动模式的预测解。ANN-LMA 技术用于评估各种情况下纳米流体的传热特性效率。将碳纳米管（包括单壁碳纳米管（SWCNT）和多壁碳纳米管（MWCNT））与氧化铁一起加入水中，这项研究证明了它们在增强传热方面的有效性。这些纳米流体具有广泛的工业应用前景，如用于增强冷却剂、癌症治疗和太阳辐射管理，并显示出良好的效果。本研究利用水基碳纳米管交叉三元杂化纳米流体的独特特性，专门研究了它们在对流加热表面上的流动特性。通过引入散热、热辐射和外部热源或散热器，实现了热传递的改善。计算求解器的性能通过误差直方图、回归分析和平均平方误差 (MSE) 结果进行了评估。对设计因素的物理意义进行了详细的图示和讨论。研究发现，辐射热通过大量积累增加了表面热能，从而提高了传热性能，而焦耳耗散和其他外部热源导致的耗散热则显著提高了流体温度。

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引用次数: 0

Predicting temperature of a Li-ion battery under dynamic current using long short-term memory 利用长短期记忆预测动态电流下锂离子电池的温度

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-16 DOI: 10.1016/j.csite.2024.105246

The growing energy demands of modern society have led to an increased reliance on secondary batteries, particularly lithium-ion (Li-ion) batteries, due to their superior energy density and power output. These batteries perform most effectively and safely within a specific temperature range, making it essential to develop accurate models for predicting temperature variations under diverse operational and environmental conditions. In particular, it is crucial to forecast temperature changes resulting from random and dynamic current fluctuations, reflecting real-world usage scenarios while considering the surrounding battery system environment. In this study, we employed a long short-term memory (LSTM) network to develop a surrogate model capable of predicting the battery’s core temperature over time, given varying current loads and heat transfer coefficients. The LSTM model demonstrated remarkable accuracy, achieving an average prediction accuracy of 99% in simulating temperature changes induced by arbitrary currents.

现代社会对能源的需求日益增长，导致人们越来越依赖二次电池，尤其是锂离子（Li-ion）电池，因为它们具有卓越的能量密度和功率输出。这些电池在特定的温度范围内能最有效、最安全地工作，因此必须开发精确的模型来预测不同操作和环境条件下的温度变化。特别是，预测随机和动态电流波动导致的温度变化至关重要，这反映了真实世界的使用场景，同时也考虑到了周围的电池系统环境。在这项研究中，我们采用了长短期记忆（LSTM）网络来开发一个替代模型，该模型能够在电流负载和传热系数不断变化的情况下预测电池核心温度随时间的变化。LSTM 模型的准确度非常高，在模拟任意电流引起的温度变化时，平均预测准确率达到 99%。

引用次数: 0

CFD investigation on flowing and discharging characteristics of airborne Halon 1301 fire-extinguishing agent at varied altitudes 不同高度下空气中哈龙 1301 灭火剂流动和排放特性的 CFD 研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-16 DOI: 10.1016/j.csite.2024.105293

To investigate the functioning mechanism of cruise altitude on transportation and discharging dynamics of onboard fire-extinguishants, a numerical model coupling the vaporization and flowing process is established for the Halon 1301-N₂ multi-component two-phase flow inside the onboard fire-extinguishing system based on computational fluid dynamics. Flowing and transportation parameters are simulated and compared for Halon 1301 at 0 m, 3000 m, 6000 m and 12000 m. Moreover, the peak discharging fluid pressure, velocity and density are also analyzed to evaluate the impact of altitude on discharging dynamics of Halon 1301. Notably, the maximum discharging velocity at 3000 m, 6000 m and 12000 m are reduced by 4 %, 9 % and 15 % relative to that at 0 m; the maximum discharging fluid pressure and density at 12000 m are respectively reduced by 32 % and 12 % relative to those at 0 m. High altitude is unraveled to inhibit the vaporization of Halon 1301 and lower the discharging efficiency at the pipeline outlet, consequently lowering the diffusion efficiency and effective concentration of Halon 1301 in the protected area and further weakening the fire-suppression effectiveness. The unveiled insights afford guidance for the optimization of fire-extinguishing systems to improve the fire-fighting capability of airplanes at high altitudes.

为了研究巡航高度对机载灭火剂运输和排放动力学的作用机理，基于计算流体动力学建立了机载灭火系统内哈龙 1301-N2 多组分两相流的汽化和流动耦合数值模型。此外，还分析了排放流体的峰值压力、速度和密度，以评估海拔高度对哈龙 1301 排放动力学的影响。值得注意的是，与 0 米高度相比，3000 米、6000 米和 12000 米高度的最大放电速度分别降低了 4%、9% 和 15%；与 0 米高度相比，12000 米高度的最大放电流体压力和密度分别降低了 32%和 12%。高海拔抑制了哈龙 1301 的汽化，降低了管道出口的排放效率，从而降低了哈龙 1301 在保护区的扩散效率和有效浓度，进一步削弱了灭火效果。这些见解为优化灭火系统，提高飞机在高空的灭火能力提供了指导。

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引用次数: 0

The effect of solar thermal energy storage on natural gas heating systems: An experimental and techno-economic investigation 太阳能热储对天然气供热系统的影响：实验和技术经济调查

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-15 DOI: 10.1016/j.csite.2024.105287

This study investigates the storage of solar thermal energy using thermal oils in Kilis, Türkiye, a region characterized by high solar potential. Both experimental and modeling studies were conducted. Mobiltherm 605 and PO Heat Transfer Oil 32 were tested as alternatives to commonly used oils. PO Heat Transfer Oil 32 was introduced to the literature for the first time. The impact of operating temperature, water flow rate, and outdoor temperature on the efficiency of stored thermal energy in the water heating system was examined. The findings revealed that system efficiency averaged 42 % at a nighttime outdoor temperature of 9 °C but decreased to 36 % at 13.5 °C. Efficiency was also 36 % at a flow rate of 0.7 m/s, decreasing to 24 % at 0.24 m/s. Mobiltherm 605 cooled down later than PO 32 in the thermal tank, indicating a higher heat transfer coefficient for PO 32. Based on experimental data, a model of the thermal storage system was developed, and its techno-economic feasibility was assessed. Using this model, a techno-economic analysis was performed and the potential for this clean energy to reduce reliance on natural gas combi boilers for heating was discussed. For a building with a maximum indoor-outdoor temperature difference of 20 °C and a heating requirement of 467 kWh over 14 h, the thermal energy cost was estimated to be $0.029/kWh. This implementation reduced carbon emissions by 130 kg/day. The total equipment cost for the thermal storage system, with a U-type Vacuum Tube Collector (U-VTC) area of approximately 380 m², was $295,697. In conclusion, both Mobiltherm 605 and PO Heat Transfer Oil 32 demonstrated comparable price/performance ratios relative to common oils.

本研究调查了在图尔基耶的基利斯使用导热油储存太阳热能的情况，该地区的太阳能潜力很高。研究同时进行了实验和建模。Mobiltherm 605 和 PO 导热油 32 作为常用导热油的替代品接受了测试。PO 导热油 32 是首次出现在文献中。研究了工作温度、水流量和室外温度对水加热系统中存储热能效率的影响。研究结果表明，当夜间室外温度为 9 °C 时，系统效率平均为 42%，但当温度为 13.5 °C 时，系统效率降至 36%。流速为 0.7 米/秒时，效率也为 36%，流速为 0.24 米/秒时，效率降至 24%。在保温箱中，Mobiltherm 605 的冷却时间比 PO 32 晚，这表明 PO 32 的传热系数更高。根据实验数据，开发了一个蓄热系统模型，并对其技术经济可行性进行了评估。利用该模型进行了技术经济分析，并讨论了这种清洁能源在减少对天然气联合锅炉供热依赖方面的潜力。对于一栋室内外最大温差为 20 °C、14 小时供暖需求为 467 千瓦时的建筑，热能成本估计为 0.029 美元/千瓦时。这一实施方案减少了 130 千克/天的碳排放量。蓄热系统的设备总成本为 295 697 美元，U 型真空管集热器（U-VTC）的面积约为 380 平方米。总之，与普通油相比，美孚 605 和 PO 导热油 32 的性价比相当。

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引用次数: 0

Entropy optimization of MHD second-grade nanofluid thermal transmission along stretched sheet with variable density and thermal-concentration slip effects 具有可变密度和热浓度滑移效应的 MHD 二级纳米流体沿拉伸片热传导的熵优化

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-15 DOI: 10.1016/j.csite.2024.105288

The goal of present investigation is to explore the influence of exponential variable density and entropy optimization on second-grade nanofluid heating efficiency and mass-concentration transmission along extended surface using external magnetic-field and temperature-concentration slip effects. To enhance the motion of nanoparticles and thermal efficiency, the influence of exponential form of temperature-based density on magnetically charged second-grade nanomaterial is main novelty of this research. For higher temperature difference, the entropy optimization is used. The defined formulation of stream functions and similarities are used to convert leading second-grade nanofluid model into ordinary differential form. The efficient Keller box method and Newton Raphson technique are applied to compute numerical results. The final algebraic equations are solved through global matrix for unknown physical quantities. The consequence of all physical constraints on velocity/U profile, temperature/θ field, concentration/ϕ shapes, skin friction coefficient, Nusselt and Sherwood number are analyzed pictorially and numerically. The following range of parameters 0.1 ≤

ξ

≤ 2.0, 0.0 ≤

n

≤ 1.2, 0.1 ≤

E_{c}

≤ 2.0, 0.07 ≤

P_{r}

≤ 7.0, 0.01 ≤

N_{t}

≤ 0.8, 0.01 ≤

N_{b}

≤ 0.9 is used. It is found that velocity field increases with maximum amplitude as variable density, magnetic force and temperature-slip constraint. It is noted that the slip behavior in temperature field and concentration field are increased with convective boundary conditions. It is depicted that local Nusselt quantity and local Sherwood quantity increases as buoyancy force and Prandtl coefficient increases.

本研究的目标是利用外部磁场和温度-浓度滑移效应，探索指数变密度和熵优化对二级纳米流体加热效率和质量-浓度沿扩展表面传输的影响。为了提高纳米粒子的运动和热效率，基于温度的指数形式密度对带磁二级纳米材料的影响是本研究的主要创新点。对于更高的温差，采用了熵优化。利用定义的流函数公式和相似性将领先的二级纳米流体模型转换为常微分形式。采用高效的 Keller box 方法和 Newton Raphson 技术计算数值结果。通过全局矩阵求解未知物理量的最终代数方程。对速度/U 曲线、温度/θ 场、浓度/j 形状、表皮摩擦系数、努塞尔特数和舍伍德数等所有物理约束条件的后果进行了图像和数值分析。使用的参数范围如下 0.1 ≤ ξ ≤ 2.0, 0.0 ≤ n ≤ 1.2, 0.1 ≤ Ec ≤ 2.0, 0.07 ≤ Pr ≤ 7.0, 0.01 ≤ Nt ≤ 0.8, 0.01 ≤ Nb ≤ 0.9。结果发现，随着密度、磁力和温度-滑移约束条件的变化，速度场以最大振幅增加。注意到温度场和浓度场的滑移行为在对流边界条件下有所增加。随着浮力和普朗特系数的增加，局部努塞尔特量和局部舍伍德量也随之增加。

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引用次数: 0