Case Studies in Thermal Engineering最新文献_第6页

Preparation and mechanism analysis of a nano-reinforced environmentally friendly composite gel for coal spontaneous combustion prevention 用于防止煤炭自燃的纳米增强型环保复合凝胶的制备及其机理分析

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-10 DOI: 10.1016/j.csite.2024.105270

Coal spontaneous combustion (CSC) has consistently been a serious safety and environmental concern in the coal industry. A nano-reinforced environmentally friendly composite gel was prepared in this study for air-leakage plugging and CSC prevention. Polyacrylamide, polydopamine, sodium lignosulfonate, phytic acid, epigallocatechin gallate and carbon nanofibers were used as raw materials. The chemical composition, crystallization and morphological structure of the novel gel were characterized. The crosslinked gel of polyacrylamide and polydopamine play a role in moisturizing and encapsulation. The expanded gel formed a carbon layer, effectively isolating the coal surface from the air. The composite gel delayed the second stage of CSC by approximately 20 %. The average heat release during the combustion stage was reduced from 8910 J/g to 7027 J/g, representing a reduction of approximately 26.8 %. The absorption intensity of the typical combustion gas products, CO₂ and CO, significantly decreased, and the rising trend was slow below 430 °C. The ultimate pressure of the air leakage plugging was 1.27 kPa. Through analyzing the inhibition and plugging mechanisms of a composite gel, this study provides a more efficient and sustainable solution for inhibiting CSC in goaf, which can enhance production safety, reduce environmental pollution, and minimize losses.

煤炭自燃（CSC）一直是煤炭行业严重的安全和环境问题。本研究制备了一种纳米增强型环保复合凝胶，用于堵塞漏风和防止煤炭自燃。以聚丙烯酰胺、聚多巴胺、木质素磺酸钠、植酸、表没食子儿茶素没食子酸酯和纳米碳纤维为原料。对新型凝胶的化学成分、结晶和形态结构进行了表征。聚丙烯酰胺和聚多巴胺交联凝胶起到了保湿和包裹的作用。膨胀后的凝胶形成了碳层，有效地将煤表面与空气隔离。复合凝胶将 CSC 的第二阶段延迟了约 20%。燃烧阶段的平均放热量从 8910 焦耳/克降至 7027 焦耳/克，降幅约为 26.8%。典型燃烧气体产物 CO2 和 CO 的吸收强度明显降低，在 430 °C 以下上升趋势缓慢。漏气堵塞的极限压力为 1.27 kPa。本研究通过分析复合凝胶的抑制和堵塞机理，为抑制棉籽油中的 CSC 提供了一种更高效、更可持续的解决方案，可提高生产安全性、减少环境污染并最大限度地降低损失。

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引用次数: 0

Optimised prediction of tunnel fire heat release rate using the ResNet18_2CLSTM model with bagging for multimodal data 使用针对多模态数据的袋集 ResNet18_2CLSTM 模型优化隧道火灾热释放率预测

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-10 DOI: 10.1016/j.csite.2024.105268

Accurate predictions of HRR will improve preparedness and response strategies, enhance safety, and minimise damage in tunnel fires. In this study, a deep learning prediction model for HRR under multimodal data fusion is proposed. A multimodal dataset is first established to obtain flame images and flue gas time series data through model-scale tunnel fire experiments. During the model training process, ResNet18 was used to extract features from the flame image, and 2CLSTM was employed to understand the time series of the flame image features and flue gas features to establish the correlation with the HRR. It was evaluated that the error analyses of the measured and predicted values of the validation set yielded R² greater than 0.85, with errors and standard deviations less than 4 kW. And the model predicted better in the flame growth and decay phases. However, there is some deviation in the predictions near the peak HRR. To address this issue, the Bagging algorithm was introduced to optimise the model. The results show that the ResNet18_2CLSTM model with Bagging reduces the RMSE by 20.47 % and increases the R² by 4.64 % compared to the original model, and the accuracy is greatly improved.

对 HRR 的准确预测将改善隧道火灾的准备和应对策略，提高安全性，并将损失降到最低。本研究提出了一种多模态数据融合下的 HRR 深度学习预测模型。首先建立多模态数据集，通过模型尺度的隧道火灾实验获取火焰图像和烟气时间序列数据。在模型训练过程中，使用 ResNet18 提取火焰图像特征，并使用 2CLSTM 理解火焰图像特征和烟道气体特征的时间序列，从而建立与 HRR 的相关性。经评估，验证集的测量值和预测值的误差分析得出 R2 大于 0.85，误差和标准偏差小于 4 千瓦。模型在火焰增长和衰减阶段的预测效果较好。然而，在峰值 HRR 附近的预测值存在一些偏差。为解决这一问题，引入了 Bagging 算法来优化模型。结果表明，采用 Bagging 算法的 ResNet18_2CLSTM 模型与原始模型相比，均方根误差降低了 20.47 %，R2 提高了 4.64 %，准确度大大提高。

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引用次数: 0

Research on multi-energy coupled preheating system of city gate station based on Modelica simulation 基于 Modelica 仿真的城门站多能源耦合预热系统研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-10 DOI: 10.1016/j.csite.2024.105279

Natural gas depressurization at city gate stations can cause hydrate formation, necessitating preheating before pressure regulation. To reduce the high energy consumption of traditional city gate station preheating processes, this study introduces four novel multi-energy coupled systems: photovoltaic-air source heat pump (PV-ASHP), solar thermal-combined heat and power-ASHP (ST-CHP-ASHP), CHP-ASHP, and ASHP system, with a typical city gate station in Shanghai taken as the research case. Dynamic energy simulation systems were developed in Dymola software to evaluate the proposed systems from energy, environmental, and economic perspectives, conducting a comparison with conventional boiler preheating systems, including sensitivity analysis of energy prices on system economics. Results indicate PV-ASHP has the lowest annual total cost (ATC) and shortest discounted payback period, while ATC values for ST-CHP-ASHP, CHP-ASHP, and ASHP increase by 6.4 %, 9.6 %, and 12.6 %, respectively. ST-CHP-ASHP and PV-ASHP demonstrate advantages in primary energy rate and carbon emissions, with ST-CHP-ASHP performing slightly better than PV-ASHP. Currently, PV-ASHP demonstrates the highest development potential. If photovoltaic feed-in tariffs remain constant, and natural gas prices decrease by over 12.5 % or CHP feed-in tariffs increase by over 38.4 %, ST-CHP-ASHP becomes more economically viable. This research provides valuable insights for retrofitting China's existing city gate station preheating systems.

城市门站的天然气减压会导致水合物的形成，因此需要在压力调节前进行预热。为了降低传统城门站预热过程的高能耗，本研究以上海典型的城门站为研究案例，介绍了四种新型多能源耦合系统：光伏-空气源热泵（PV-ASHP）、太阳能光热-热电联产-ASHP（ST-CHP-ASHP）、热电联产-ASHP 和 ASHP 系统。利用 Dymola 软件开发了动态能源仿真系统，从能源、环境和经济角度对拟议系统进行评估，并与传统锅炉预热系统进行比较，包括能源价格对系统经济性的敏感性分析。结果表明，PV-ASHP 的年总成本（ATC）最低，贴现投资回收期最短，而 ST-CHP-ASHP、CHP-ASHP 和 ASHP 的 ATC 值分别增加了 6.4%、9.6% 和 12.6%。ST-CHP-ASHP 和 PV-ASHP 在一次能源利用率和碳排放量方面都具有优势，其中 ST-CHP-ASHP 的表现略好于 PV-ASHP。目前，PV-ASHP 的发展潜力最大。如果光伏发电上网电价保持不变，而天然气价格下降超过 12.5%，或热电联产上网电价上涨超过 38.4%，ST-CHP-ASHP 在经济上就更加可行。这项研究为改造中国现有的城门站预热系统提供了宝贵的见解。

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引用次数: 0

An insight into the combustion analysis of low carbon alcohol infused ternary fuel blends operated by varying the compression ratios 通过改变压缩比对注入低碳酒精的三元混合燃料的燃烧分析进行深入研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.csite.2024.105251

To address the growing scarcity and rising costs of fossil fuels, researchers are exploring alternative energy sources that can mimic the conventional fuels. This study focused on ternary fuel blends made from waste fried oil (WFO) biodiesel, methanol, and diesel. To enhance their stability, 10, 20, and 30 ml of n-butanol per litre of ternary blends are added. The blends were tested in a variable compression ratio (VCR) engine under peak load conditions. The experiments are carried out by varying the compression ratio (CR) of the engine from 16:1 to 18:1. The results showed that increasing the CR improved combustion for all fuel blends. Among the ternary blends, B30M20D50 outperformed pure diesel in terms of combustion characteristics. When compared to diesel, B30M20D50 yielded 5.08 %, 5.31 %, and 4.59 % higher P_max at CR 16:1, 17:1, and 18:1, respectively. Under the same conditions, NHRR outperformed diesel by 1.46 %, 3.12 %, and 2.44 %, respectively. While ternary blends with up to 20 % methanol exhibited stable combustion, higher methanol concentrations led to erratic rise in the coefficient of variation. The interdependency analysis revealed a strong correlation between the combustion parameters for the B20M30D50 blend across different compression ratios.

为解决化石燃料日益稀缺和成本不断上涨的问题，研究人员正在探索可模拟传统燃料的替代能源。这项研究的重点是用废弃油炸生物柴油、甲醇和柴油制成的三元燃料混合物。为了提高其稳定性，每升三元混合燃料中分别添加了 10、20 和 30 毫升正丁醇。在峰值负荷条件下，在可变压缩比（VCR）发动机中对这些混合物进行了测试。实验中，发动机的压缩比（CR）从 16:1 变为 18:1。结果表明，提高压缩比可以改善所有混合燃料的燃烧。在三元混合燃料中，B30M20D50 的燃烧特性优于纯柴油。与柴油相比，在 CR 为 16:1、17:1 和 18:1 时，B30M20D50 的 Pmax 分别高出 5.08%、5.31% 和 4.59%。在相同条件下，NHRR 的性能分别比柴油高 1.46 %、3.12 % 和 2.44 %。甲醇含量不超过 20% 的三元共混物表现出稳定的燃烧，而甲醇浓度越高，变异系数上升越不稳定。相互依存关系分析表明，不同压缩比的 B20M30D50 混合燃料的燃烧参数之间存在很强的相关性。

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引用次数: 0

Multi-objective topology optimization and numerical investigation of heat sinks based on triply periodic minimal surface lattices 基于三周期极小曲面网格的散热器多目标拓扑优化和数值研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.csite.2024.105255

In thermal management applications, such as heat sinks (HSs) for electronic devices, cellular materials have extensively been employed. In recent years, there has been a growing attention towards employing topology optimization for enhancing hydraulic and heat transfer performance of HSs by optimizing their topology. The utilization of triply periodic minimal surface (TPMS) based structures presents distinctive prospects for customizing the design and performance of HSs. However, their potential remains unexplored in the context of customizing additively manufactured porous optimized HSs. Consequently, there is a need for research aimed at examining their coupled hydraulic and thermal performance. Density mapping approaches are used to build a variable density TPMS-based HSs from the output of topology optimization by applying the TPMS level-set equations that relate relative density and the level-set constant. In this work, a relative density mapping methodology is applied to thermo-fluid optimization problem to design a TPMS-based convective cooling system. An in-house MATLAB code was developed to perform a multi-objective topology optimization. After that, uniform and variable density (mapped from topology optimization results) TPMS-based HSs are analyzed using Star-CCM + CFD software to investigate their hydraulic and heat transfer performance. An experimental setup was established, and the numerical results were validated using uniform TPMS-based heat sinks. Results showed that incorporating TPMS with topology optimization has a great potential in thermal management applications as pressure drop across the heat sink was reduced while maintaining the performance.

在热管理应用中，如电子设备的散热器（HS），蜂窝材料已被广泛采用。近年来，人们越来越关注采用拓扑优化技术，通过优化散热器的拓扑结构来提高其水力和传热性能。基于三重周期性最小表面（TPMS）结构的应用为定制化 HS 的设计和性能带来了独特的前景。然而，在定制添加制造的多孔优化 HS 方面，其潜力仍有待开发。因此，有必要对其水力和热力耦合性能进行研究。密度映射法通过应用与相对密度和水平常数相关的 TPMS 水平设定方程，从拓扑优化的输出中构建基于 TPMS 的可变密度 HS。本研究将相对密度映射方法应用于热流体优化问题，以设计基于 TPMS 的对流冷却系统。我们开发了一套内部 MATLAB 代码，用于执行多目标拓扑优化。之后，使用 Star-CCM + CFD 软件分析了基于 TPMS 的均匀和变密度（根据拓扑优化结果映射）对流冷却系统，以研究其水力和传热性能。建立了实验装置，并使用基于均匀 TPMS 的散热器验证了数值结果。结果表明，将 TPMS 与拓扑优化相结合在热管理应用中具有巨大的潜力，因为在保持性能的同时，散热器上的压降得以降低。

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引用次数: 0

Utilizing numerical techniques for modeling radiating Casson nanofluid flow with thermophoretic phenomenon on a heated stretching surface 利用数值技术为受热拉伸表面上具有热泳现象的辐射卡松纳米流体流动建模

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.csite.2024.105206

This work aims to use mathematical modeling to investigate the mechanics of heat and mass transport in dissipative Casson nanofluid flows over a linear rough sheet. This study considers various elements such as thermal radiation, magnetic fields, heat generation, the varied properties of porous media, and the thermophoretic impact. Besides that, it looks into the variations in viscosity, diffusivity, and thermal conductivity, as well as the energy dissipation from viscous internal friction and fluid temperature modifications. The method involves coming up with and changing the boundary layer equations into a group of linked nonlinear ordinary differential equations that use variables that do not have any dimensions. The foundation of the solution strategy for these equations is the Hermite collocation method (HCM), which is renowned for its precision and adaptability. It offers an organized approach to solving the complex differential equations, allowing for accurate numerical solutions. The use of graphical representations ensures thorough data analysis and clarity, while also providing insightful information about the computed outcomes. The code validation method uses numerical comparisons with recent research to confirm the algorithm’s accuracy and dependability, as well as its resilience in comparison to the existing literature. Important conclusions from the study show that thermal boundary layers and nanofluid velocity decrease with increases in the porosity parameter, slip parameter, and magnetic field parameter.

这项研究旨在利用数学建模来研究线性粗糙薄片上的耗散卡松纳米流体流动中的热量和质量传输力学。这项研究考虑了各种因素，如热辐射、磁场、热量产生、多孔介质的不同特性以及热泳影响。此外，它还研究了粘度、扩散率和热导率的变化，以及粘滞内摩擦和流体温度变化产生的能量耗散。该方法包括提出边界层方程，并将其转换为一组使用无尺寸变量的关联非线性常微分方程。这些方程求解策略的基础是赫尔墨特配位法（HCM），该方法以其精确性和适应性而闻名。它为复杂微分方程的求解提供了一种有条理的方法，允许精确的数值求解。图形表示法的使用确保了彻底的数据分析和清晰度，同时还提供了有关计算结果的深刻信息。代码验证方法采用与最新研究进行数值比较的方式，以确认算法的准确性和可靠性，以及与现有文献相比的适应性。研究得出的重要结论表明，热边界层和纳米流体速度随着孔隙度参数、滑移参数和磁场参数的增加而降低。

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引用次数: 0

Variable density and heat generation impact on chemically reactive carreau nanofluid heat-mass transfer over stretching sheet with convective heat condition 不同密度和发热量对对流热条件下拉伸片上化学反应卡络纳米流体传热的影响

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.csite.2024.105260

The present study focuses on the physical significance of heat generation and chemical reaction on Carreau nanofluid with convective heat conditions. Heat transfer is characterized using convective boundary conditions. The governing partial differential equations (PDEs) are transformed into ordinary differential equations (ODEs) by using well define stream functions and similarity transformations. Using a shooting methodology, the Keller-box method with Newton Raphson scheme is used to elaborate the numerical solutions of physical phenomena. Utilizing a similar technique to find the impact of physical parameter such as the production of heat

δ

, the rate of reaction

Λ

, Biot numbers

γ

, Brownian motion variable

N_{b}

, the thermophoresis parameters

N_{t}

, the Weissenberg quantity

We

, Prandtl number

\Pr

, and Lewis number

L_{e}

on velocity profile, temperature profile and mass transmission profile are determined graphically. The skin-friction coefficient

- f^{″} (0)

, local Nusselt

- θ^{'} (0)

, and Sherwood numbers

- ϕ^{'} (0)

are analyzed numerically. Increment in fluid velocity and slip temperature are depicted with high Biot number. Maximum magnitude of fluid temperature and fluid concentration function are depicted at high value of temperature dependent density. The magnitude of heat and mass transportation enhanced with maximum choice of Brownian motion.

本研究的重点是对流热条件下 Carreau 纳米流体的发热和化学反应的物理意义。热传导采用对流边界条件。通过使用定义明确的流函数和相似变换，将支配偏微分方程（PDE）转换为常微分方程（ODE）。利用拍摄方法，采用牛顿-拉斐森方案的凯勒方框法来阐述物理现象的数值解。利用类似技术，以图形方式确定了热量产生δ、反应速率Λ、比奥特数γ、布朗运动变量 Nb、热泳参数 Nt、魏森伯格量 We、普朗特数 Pr 和路易斯数 Le 等物理参数对速度曲线、温度曲线和质量传输曲线的影响。对摩擦系数 -f″(0)、局部努塞尔特数 -θ′(0)和舍伍德数 -j′(0)进行了数值分析。流体速度和滑移温度随 Biot 数的增大而增加。流体温度和流体浓度函数的最大值取决于高温度密度值。在选择最大布朗运动时，热量和质量的传输量会增大。

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引用次数: 0

A study of the relationship between human thermal comfort and negative emotions in quarantine environments 隔离环境中人体热舒适度与负面情绪之间关系的研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.csite.2024.105253

The thermal environment is closely related to emotion. The thermal environment affects emotional experiences and can enhance them by adjusting its parameters. This study examines three common negative emotions—boredom, anxiety, and irritability—in a controlled environment. We experimentally investigated how these emotions affect thermal sensation, thermal comfort, and physiological parameters under varying temperature and humidity conditions. Results indicated that emotions significantly influenced thermal sensation (TSV) and thermal comfort (TCV) under moderate to high humidity conditions, demonstrating how temperature and humidity moderate the relationship between emotion and thermal comfort. Changes in physiological parameters further reveal how the interaction between emotion and environmental conditions affects physiological responses. A regression model was created using the response surface method to analyze thermal comfort in relation to temperature and humidity under different emotions, identifying the optimal indoor conditions as 22.8 °C and 46.7 % humidity. These findings help reduce negative emotions, improve thermal comfort, enhance our understanding of human thermal comfort, and provide scientific guidance for managing negative emotions during public health emergencies.

热环境与情绪密切相关。热环境会影响情绪体验，并能通过调整参数增强情绪体验。本研究在受控环境中研究了三种常见的负面情绪--烦恼、焦虑和烦躁。我们通过实验研究了在不同的温度和湿度条件下，这些情绪如何影响热感觉、热舒适度和生理参数。结果表明，在中高湿度条件下，情绪会明显影响热感觉（TSV）和热舒适度（TCV），这说明了温度和湿度如何调节情绪与热舒适度之间的关系。生理参数的变化进一步揭示了情绪与环境条件之间的相互作用如何影响生理反应。利用响应面法建立了一个回归模型，分析了不同情绪下温度和湿度与热舒适度的关系，确定了最佳室内条件为 22.8 °C、46.7 % 湿度。这些发现有助于减少负面情绪，改善热舒适度，加深我们对人体热舒适度的理解，并为在公共卫生突发事件中管理负面情绪提供科学指导。

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引用次数: 0

Combustion characteristics of low-concentration coal mine gas with metal fiber burners 使用金属纤维燃烧器的低浓度煤矿瓦斯燃烧特性

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.csite.2024.105256

Coal mine gas with methane concentration lower than 30 % is regarded as low-concentration gas. Currently, both domestically and internationally, coal mine gas with methane concentration ranging from 10 % to 30 % is mainly used for power generation. However, it is not easy to safely combust and treat coal mine gas with methane concentration below 10 %, which is typically directly emitted into the atmosphere, leading to energy wastage and environmental pollution. Metal fiber burners are a type of porous medium burner, suitable for fully premixed combustion, enabling the safe utilization of low-concentration gas within the explosive range. In this study, a direct combustion experimental system was designed to investigate the combustion characteristics of low-concentration coal mine gas with metal fiber burners. The results show that with an increase in the porosity and thickness of the metal fiber woven fabric, the range of area heat release rate expands, and the load adjustment ratio increases, enlarging the range of stable combustion. Single-layer woven fabric burner ignite more easily, followed by double-layer woven fabric burner, while non-woven fabric burner are the least prone to ignition. The results also indicate that when using metal fiber burners to combust low-concentration gas, the emissions of NO_x and CO in the flue gas remain at lower levels.

甲烷浓度低于 30% 的煤矿瓦斯被视为低浓度瓦斯。目前，国内外主要将甲烷浓度在 10%-30% 之间的煤矿瓦斯用于发电。然而，甲烷浓度低于 10% 的煤矿瓦斯不易安全燃烧和处理，通常直接排放到大气中，造成能源浪费和环境污染。金属纤维燃烧器是一种多孔介质燃烧器，适合全预混燃烧，可安全利用爆炸范围内的低浓度瓦斯。本研究设计了一个直接燃烧实验系统，以研究金属纤维燃烧器对低浓度煤矿瓦斯的燃烧特性。结果表明，随着金属纤维编织物孔隙率和厚度的增加，面积放热率范围扩大，负荷调节比增大，扩大了稳定燃烧的范围。单层编织物燃烧器更容易着火，其次是双层编织物燃烧器，而无纺布燃烧器最不容易着火。结果还表明，使用金属纤维燃烧器燃烧低浓度气体时，烟气中的氮氧化物和一氧化碳排放量保持在较低水平。

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引用次数: 0

A two-dimensional thin film structure with spectral selective emission capability suitable for high-temperature environments 适用于高温环境、具有光谱选择性发射能力的二维薄膜结构

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.csite.2024.105261

Spectral selective emission materials, characterized by their high emission efficiency within specific wavelength ranges, play a crucial role in various fields such as infrared stealth and radiative cooling. In this study, leveraging the tunneling effect of ultrathin metal layers and the impedance matching principle, we designed a one-dimensional multilayer thin film structure composed of Mo/Ge/Al. This design successfully achieved spectral selective emission within the 3–14 μm infrared spectrum range, showcasing superior high-temperature infrared stealth capabilities. Research findings indicate that the infrared atmospheric window (ε_{3–5 μm} = 0.40, ε_{8–14 μm} = 0.30) maintains a low emissivity within the temperature range from room temperature to 400 °C, while high emissivity in non-infrared atmospheric windows (ε_{5–8 μm} = 0.81) enables radiative cooling. The use of high emissivity in the non-infrared atmospheric window reduced the surface temperature of this structure by 15.3 °C compared to untreated Si substrate under similar heating conditions. The temperature reduction was 34.1 °C when compared to a Si substrate coated with a 200 nm Al film. This straightforward and easily scalable structure not only presents novel solutions for applications in infrared stealth and radiative cooling but also holds vast potential for diverse fields including military, aerospace, and industrial manufacturing, injecting fresh impetus and possibilities into technological advancement.

光谱选择性发射材料具有在特定波长范围内发射效率高的特点，在红外隐身和辐射冷却等多个领域发挥着重要作用。在这项研究中，我们利用超薄金属层的隧道效应和阻抗匹配原理，设计了一种由 Mo/Ge/Al 组成的一维多层薄膜结构。这一设计成功实现了 3-14 μm 红外光谱范围内的光谱选择性发射，展示了卓越的高温红外隐身能力。研究结果表明，红外大气窗（ε3-5 μm = 0.40，ε8-14 μm = 0.30）在室温到 400 ℃ 的温度范围内保持了低发射率，而非红外大气窗的高发射率（ε5-8 μm = 0.81）则实现了辐射冷却。在类似的加热条件下，与未经处理的硅基底相比，在非红外大气窗口中使用高发射率可使该结构的表面温度降低 15.3 °C。与涂有 200 纳米铝膜的硅基板相比，温度降低了 34.1 °C。这种简单易行、易于扩展的结构不仅为红外隐身和辐射冷却应用提供了新的解决方案，而且在军事、航空航天和工业制造等不同领域也蕴藏着巨大的潜力，为技术进步注入了新的动力和可能性。

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引用次数: 0