Case Studies in Thermal Engineering最新文献_第9页

Swirl-induced mixing improvement in absorber tubes of parabolic trough solar collectors 抛物面槽型太阳能集热器吸收管涡流诱导混合的改进

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107579

Anissa Ghomrassi , Salma Benzarti , Monia Chaabane , Hatem Mhiri , Hervé Bournot

In this study, for the first time, the working fluid is introduced into the absorber of the parabolic trough collector (PTC) through tangential inlets. This new configuration induces a swirl motion. Multiple tangential inlets are strategically positioned along the tube, including arrangements with one inlet, two inlets, three inlets and four inlets. Simulations are conducted at various Reynolds numbers (Re), from 2000 to 10000. The findings exhibit that a significant augmentation in heat transfer is observed, as the Nusselt number (Nu) nearly doubles when tangential injections are introduced compared to the smooth tube case. This is due to enhanced heat transfer resulting from vortex generation, rapid exchange, and improved mixing within the flow. Additionally, the mixing effect helps to balance the temperature distribution by reducing the disparity between the lower portion of the receiver tube, subjected to focused solar irradiation, and the upper portion, which mainly receives direct solar exposure. Furthermore, receiver tube equipped with one tangential inlet gives an average thermal performance factor (TPF) of 1,31. A new empirical correlation describing TPF in function of Re, inlets number and Swirls number is developed. This expression provides an accurate fit to the numerical data with a coefficient of determination R² = 0.9361 and an average prediction error below 3.9 %.

在本研究中，首次将工作流体通过切向入口引入抛物槽集热器（PTC）的吸收器。这种新的结构引起了涡流运动。多个切向入口沿管战略性地定位，包括一个入口、两个入口、三个入口和四个入口的布置。模拟在不同雷诺数（Re）下进行，从2000到10000。研究结果表明，当引入切向注入时，与光滑管情况相比，努塞尔数（Nu）几乎翻了一番，传热显著增加。这是由于涡流产生、快速交换和流动中混合改善导致的热传递增强。此外，混合效应通过减小受太阳聚焦照射的接收管下部与主要接受太阳直射的接收管上部之间的差异，有助于平衡温度分布。此外，配备一个切向入口的接收管的平均热性能因子（TPF）为1,31。建立了一种描述TPF与Re、入口数和旋流数之间关系的经验关系式。该表达式与数值数据拟合较好，决定系数R2 = 0.9361，平均预测误差小于3.9%。

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引用次数: 0

Comparative numerical analysis of various baffled heat exchangers with existence of baffle-to-shell clearance 考虑隔板与壳间隙的不同折流板换热器的数值比较分析

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107580

Lu Ma , Leigang Zhang , Baiqiang Zhang , Yuhui Chen , Bo Zhang , Ke Wang

The presence of baffle-to-shell clearance compromises shell side thermal efficiency of shell-and-tube heat exchangers (STHEs). This study investigates the effectiveness of sealing strips in mitigating flow maldistribution for the shell side of STHEs with such clearance. Periodic numerical models were established and validated for three typical STHE configurations: segmental, helical and trefoil-hole baffled exchangers. The effect of sealing strips under triangular and squared tube layout across typical baffle configurations was evaluated quantitatively with respect to shell-side performance. The sealing strips increased both heat transfer coefficient and pressure drop in segmental and helical configurations; however, their influence on trefoil-hole baffled exchangers was negligible. The comprehensive performance index, h(Δp)^−1/3, increased by 4.63–6.76 % and 2.09–4.12 % for segmental baffled STHEs with sealing strips in staggered and aligned tube arrangement, respectively. Whereas for corresponding helical configurations, the same index decreased by 23.01–26.62 % and 19.51–21.95 %, indicating the limited or even negative effect of sealing strips for helical baffles. The acceptability of sealing strips in helical and trefoil-hole baffled STHEs, especially for multiple-pass design and diverse operating conditions, warrants dedicated investigation.

折流板与壳间隙的存在会影响管壳式换热器的壳侧热效率。本研究探讨了密封条在具有这种间隙的STHEs壳体侧缓解流动不均匀分布的有效性。建立并验证了三种典型STHE结构：节段式、螺旋式和三叶孔折流板交换器的周期性数值模型。对典型折流板配置下三角形管和方形管布置下密封条对壳侧性能的影响进行了定量评价。密封条增加了段形和螺旋形的换热系数和压降；然而，它们对三叶草孔挡板换热器的影响可以忽略不计。采用错开密封条和排列密封条的节段折流板换热器，其综合性能指标h（Δp）-1/3分别提高了4.63 ~ 6.76%和2.09 ~ 4.12%。而对于相应的螺旋结构，该指标分别降低了23.01 ~ 26.62%和19.51 ~ 21.95%，说明密封条对螺旋挡板的作用有限甚至是负面的。在螺旋和三叶孔挡板sts中，密封条的可接受性，特别是在多通道设计和不同的操作条件下，需要进行专门的研究。

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引用次数: 0

Turbulent natural convection in isothermally heated open-ended building shafts: Numerical analysis of ventilation performance 等温加热开放式建筑竖井中的湍流自然对流：通风性能的数值分析

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107553

Maram Ammar , Charbel Ziade , Aram Yeretzian , Fadl Moukalled , Issam Lakkis

We investigate buoyancy-driven ventilation in open-ended building shafts whose walls are isothermally heated, aiming to quantify passive removal of warm, polluted air from pedestrian-level urban canyons. Three-dimensional RANS CFD simulations (SST

k - ω

) are carried out for a 36 m building containing a central shaft of height

H = 32

m with square cross-sections

b = 2

, 3, and 4 m and wall–ambient temperature differences

Δ T = 10,

20, 3 0^{\circ} C

, corresponding to

R a \approx 2.9 \times 1 0^{13}

-

7.6 \times 1 0^{13}

(turbulent regime). A sensitivity study comparing far-field boundaries modeled as stationary walls versus zero gauge pressure outlets shows that the resulting mass flow rates differ by less than 10 %. The flow remains developing along the shaft and exhibits inlet separation with a delayed reattachment in wider shafts; three zones are identified: recirculation, core-flow, and boundary-dominated. Predicted mass flow rates span 3.76

- -

16.63 kg/s

, with ventilation effectiveness (mass flow per unit heat input) 0.179–0.645 kg/kJ; increasing

b

improves effectiveness, whereas increasing

Δ T

enhances heat transfer faster than mass flow, reducing effectiveness. Partial validation against Churchill–Chu correlations for an isothermal vertical plate shows average Nusselt numbers within

\leq 15

% over most of the plate length. Two simplified models (a stack model with losses and a 1-D model) capture trends but underpredict 3-D effects tied to corner dynamics and entry recirculation; accuracy improves when the stack model uses a friction factor inferred from wall shear. From the CFD data, we propose building-scale correlations for the average Nusselt number, effective friction factor, and entry length as functions of Rayleigh number and aspect ratio

b / H

, to guide preliminary design of passively ventilated shafts in urban settings.

我们研究了开放式建筑竖井的浮力驱动通风，其墙壁是等温加热的，旨在量化从行人水平的城市峡谷中被动去除温暖的污染空气。三维RANS CFD模拟（SST k−ω）是对一个36米建筑进行的，该建筑的中心轴高度为H=32 m，横截面为b=2、3和4 m，墙体-环境温差ΔT=10、20、30°C，对应于Ra≈2.9×1013−7.6×1013（湍流区）。一项灵敏度研究比较了远场边界模型为固定壁面和零表压力出口，结果表明质量流率相差不到10%。流动沿轴继续发展，在较宽的轴上表现出进口分离和延迟再附着；确定了三个区域：再循环、核心流和边界主导。预测质量流量范围为3.76 ~−16.63kg/s，通风效率（单位热量输入质量流量）为0.179 ~ 0.645 kg/kJ；增加b提高效率，而增加ΔT比质量流更快地增强传热，降低效率。对等温垂直板的Churchill-Chu相关性的部分验证表明，在大部分板长上，平均努塞尔数≤15%。两种简化模型（含损失的叠加模型和一维模型）捕捉了趋势，但低估了与拐角动态和入口再循环相关的三维效应；当叠加模型使用从壁面剪力推断出的摩擦系数时，精度得到了提高。根据CFD数据，我们提出了平均努塞尔数、有效摩擦系数和入口长度作为瑞利数和纵横比b/H函数的建筑尺度相关性，以指导城市被动通风竖井的初步设计。

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引用次数: 0

Study on the temperature variation characteristics of subway vehicles interior fire based on realistic scenarios 基于真实场景的地铁车辆内部火灾温度变化特征研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107523

Yan Huo , Xin Tian , Yong Sun , Ruonan Li , Gaowan Zou , Xueyan Xu

Subway vehicle fire incidents pose significant safety challenges, making it crucial to understand temperature variation characteristics. Realistic fire scenarios in subway vehicles involve dynamic door opening and air conditioning ventilation, both of which greatly impact temperature variations. However, existing research has not addressed the impact of these factors. This paper addresses this gap by proposing three predictive models for temperature variation. First, a 150 kW fire source experiment is analyzed across 6 scenarios, revealing that the maximum temperature rise may occur either before or after door opening, indicating that models for before and after door opening should be studied independently. Second, CFD simulations are conducted across 70 scenarios to analyze temperature variations, identifying fire source location, fire source power, and air conditioning ventilation speed as key factors influencing temperature variation in realistic fire scenarios. Third, based on the simulation data and key factors, a maximum temperature rise model, a maximum temperature difference model, and a temperature attenuation model are proposed to predict interior temperature variations in realistic fire scenarios. Finally, comparisons between these models and experimental results showed root mean square errors of 10.5 °C and 9.07 °C for the maximum temperature rise and attenuation models, respectively, with the experimental data for the maximum temperature difference also complying with the model's range. This paper provides a theoretical basis for accurately predicting temperature variation in realistic subway vehicle fire scenarios, offering meaningful insights for improving fire safety measures and emergency response strategies.

地铁车辆火灾事故带来了重大的安全挑战，因此了解温度变化特征至关重要。地铁车辆火灾的真实场景涉及动态开门和空调通风，两者对温度变化的影响都很大。然而，现有的研究并没有解决这些因素的影响。本文通过提出三种温度变化的预测模型来解决这一差距。首先，对150kw火源实验进行了6个场景的分析，发现最大温升可能出现在开门前，也可能出现在开门后，因此需要独立研究开门前和开门后的模型。其次，对70个场景进行CFD模拟，分析温度变化，确定火源位置、火源功率和空调通风速度是影响真实火灾场景温度变化的关键因素。第三，基于模拟数据和关键因素，提出了预测真实火灾场景下室内温度变化的最大温升模型、最大温差模型和温度衰减模型。最后，将这些模型与实验结果进行比较，最大温升模型和衰减模型的均方根误差分别为10.5°C和9.07°C，最大温差的实验数据也符合模型的范围。本文为准确预测地铁车辆火灾真实场景下的温度变化提供了理论依据，为完善消防安全措施和应急响应策略提供了有意义的见解。

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引用次数: 0

Double-encapsulated phase change material microcapsules with paraffin shell for PV cooling: Experimental and performance analysis 光伏冷却用石蜡壳双封装相变材料微胶囊：实验与性能分析

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107556

Yue Liu , Tianen Chen , Xinyu Song , Lin Han , Fanbin Meng , Shifeng Wang

Energy is indispensable in modern society. Solar Photovoltaic (PV) technology has gained increasing popularity due to its notable power generation advantages. However, PV modules face a critical “temperature-efficiency” contradiction during energy conversion: only about 20 % of solar radiation is converted into electricity, while the remaining energy accumulates as heat, leading to significant performance degradation. To address this issue, our experiment employs a novel cooling technology-phase-change microcapsule cooling. By utilizing the heat absorption and release during the phase transition of the microcapsules, the temperature of PV modules is effectively regulated. Furthermore, the phase-change microcapsules designed in this work innovatively introduce paraffin as a secondary shell material, which improves thermal cycling stability. After 200 thermal cycles, the enthalpy loss remains negligible, with a retained enthalpy of 188.8 J/g. The microcapsules were applied to the back of PV modules, and field tests were conducted in Lhasa (91°06′ E, 29°36′ N). The results show a maximum temperature reduction of 16 °C (average: 4.66 °C) on the front side and 15 °C (average: 4.33 °C) on the back side, along with an increase in Pmax (P_max) of up to 11.11 % (average: 4.55 %). This study not only advances the development of bio-inspired encapsulation techniques for novel phase-change microcapsules, but also provides an innovative thermal-management solution for PV modules operating in extreme environments.

能源在现代社会是不可或缺的。太阳能光伏（PV）技术由于其显著的发电优势而越来越受欢迎。然而，光伏组件在能量转换过程中面临着一个关键的“温度-效率”矛盾：只有大约20%的太阳辐射被转化为电能，而剩余的能量积累为热量，导致性能显著下降。为了解决这个问题，我们的实验采用了一种新的冷却技术——相变微胶囊冷却。利用微胶囊相变过程中的热量吸收和释放，可以有效调节光伏组件的温度。此外，本文设计的相变微胶囊创新性地引入了石蜡作为二次壳材料，提高了热循环的稳定性。经过200个热循环后，焓损失仍然可以忽略不计，保留焓为188.8 J/g。将微胶囊应用于光伏组件背面，并在拉萨（91°06′E, 29°36′N）进行现场试验。结果表明，前侧面最大温度降低了16°C（平均4.66°C），背面最大温度降低了15°C（平均4.33°C）， Pmax （Pmax）增加了11.11%（平均4.55%）。该研究不仅推动了新型相变微胶囊仿生封装技术的发展，而且为光伏组件在极端环境下的运行提供了一种创新的热管理解决方案。

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引用次数: 0

Influence of transverse fire locations on hot smoke movement and critical driving force of bifurcated tunnel fire under forced ventilation 火灾横向位置对强制通风条件下分叉隧道火灾热烟运动及临界驱动力的影响

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107596

Binrui Li , Hongqing Zhu , Baolin Qu , Xin Li , Jingxin Wang

Fire hazard on both sides of tunnel is significantly higher than in the middle, and the tunnel walls and bifurcation areas significantly affect the flow of hot smoke and subsequent effective control, causing serious fire hazards. The smoke movement and critical ventilation threshold to prevent smoke backlayering in bifurcated tunnel fire are studied. The results show that when the fire occurs in the bifurcation area, the hot smoke generated is more difficult to be completely suppressed. When the distance between the fire and the side wall of the tunnel decreases from 9 m to 1 m, the slope k gradually decreases from 2.365 to 1.708 and V shows a “decreasing-increasing-decreasing”. When the distance between the fire source and the side wall of the tunnel is 3 m, the maximum intercept b is −1.181. The hot smoke at H4 is more difficult to be completely suppressed. For smoke movement, the side wall of the main tunnel limits free diffusion and promotes smoke shock and asymmetric flow. As the fire gradually approaches the side wall, the dominant factor of smoke movement changes from bifurcation flow to the limiting and guiding effect of the side wall of the tunnel. Combined with the theoretical formula, the forced ventilation driving force to prevent smoke backlayering at different transverse fire locations is deduced. This study provides insights for tunnel fire prevention and control by examining hot smoke movement and management under realistic engineering conditions.

隧道两侧的火灾危险性明显高于中间，隧道壁面和分岔区域对热烟的流动及后续有效控制影响较大，造成严重的火灾危险性。研究了分叉隧道火灾中烟气的运动规律和防止烟气反分层的临界通风阈值。结果表明，当火灾发生在分岔区域时，产生的热烟更难被完全抑制。当火灾与隧道侧壁的距离从9 m减小到1 m时，斜率k从2.365逐渐减小到1.708，V呈现“减小-增大-减小”的趋势。当火源与隧道侧壁距离为3 m时，最大截距b为−1.181。H4的热烟更难被完全抑制。对于烟的运动，主隧道侧壁限制了烟的自由扩散，促进了烟的激波和不对称流动。随着火灾逐渐逼近侧壁，烟雾运动的主导因素由分岔流变为巷道侧壁的限制和引导作用。结合理论公式，推导了不同横向火源位置防止烟反层的强制通风驱动力。本研究通过对实际工程条件下热烟运动和管理的研究，为隧道火灾的防治提供了新的思路。

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引用次数: 0

Study on the influence of oil jet angle on oscillatory flow and heat transfer non-uniformity in piston dual cooling galleries 油射流角度对活塞双冷却腔内振荡流动和换热不均匀性影响的研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107531

Bo Yu, Xiwen Deng, Jilin Lei

Oscillatory cooling is an effective technology for enhancing piston heat transfer. However, traditional designs often overlook the non-uniformity of piston surface temperature caused by intake air cooling. A computational fluid dynamics (CFD) model was developed for a diesel piston with a dual cooling gallery, incorporating various cooling oil jet angles, to investigate how variations in jet angle influence internal flow and heat transfer non-uniformity. The results show that the right gallery exhibits less variation in heat transfer than the left. As the distance between the galleries increased, the amplitude of the instantaneous heat transfer coefficient gradually decreased, with a minimal variation of only 11.91 % observed under the R-d10(−2°) condition. When d = 10 mm, the sample standard deviation of the steady-state heat transfer coefficient on the right oil gallery reaches its minimum value of 56, while the overall variation of the coefficient is 156 W/(m²·K), indicating a more uniform heat transfer distribution. Based on the simulation data, a correlation was established to describe the relationship among jet angle, engine speed, distance, and fluid charge ratio. The fitting errors were 4.0 % for the left gallery and 11.1 % for the right gallery. The predictive model developed in this study supports the optimization of injection strategies and structural parameters, providing a theoretical basis for the heat transfer enhancement design of internal oil galleries in high efficiency diesel engine pistons.

振荡冷却是提高活塞传热的有效技术。然而，传统的设计往往忽略了进气冷却引起的活塞表面温度的不均匀性。建立了考虑不同冷却油喷射角度的双冷却廊柴油活塞计算流体动力学（CFD）模型，研究了喷射角度变化对活塞内部流动和传热不均匀性的影响。结果表明，右侧走廊的传热变化小于左侧走廊。随着通道间距离的增加，瞬时换热系数的幅值逐渐减小，在R-d10（−2°）条件下，瞬时换热系数的幅值变化最小，仅为11.91%。当d = 10 mm时，右侧油廊稳态传热系数的样本标准差达到最小值56，而该系数的总体变化量为156 W/(m2·K)，表明传热分布更为均匀。基于仿真数据，建立了喷流角与发动机转速、距离和充液比之间的关系式。左腔的拟合误差为4.0%，右腔的拟合误差为11.1%。本研究建立的预测模型支持了喷射策略和结构参数的优化，为高效柴油机活塞内部油腔强化传热设计提供了理论依据。

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引用次数: 0

Theoretical confirmation of temperature gradient characteristics in concrete bridges through refined thermal analysis 混凝土桥梁温度梯度特性的精细化热分析理论验证

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107572

Yin-Gang Wang , Xiong-Jun He , Qiong Nie , Zhi-Yuan Cheng

Bridge temperature gradient models are critical for assessing temperature effects, with their shape and magnitude remaining a central concern in the engineering community. Existing thermal modeling exhibits limitations in accounting for radiative heat exchange between a bridge and its environment, particularly in distinguishing thermal contributions from sunlit versus shaded ground areas. To address this gap, this study innovatively develops an algorithm that dynamically tracks changes in radiative view factors from bridge surfaces to ground shadows. Through refined thermal analysis of a conventional concrete box girder using one-month measured weather data, key findings include: 1) The shape of vertical temperature gradient (VTG) shows the closest alignment with both exponential curves and 5th-order parabolas specified in bridge design codes, with a marginally better fit for the former; 2) The VTG “zero” point typically occurs at around 1.2 m girder depth; 3) Bridge orientation induces significant VTG variations up to 3.4 °C, with east-west alignments exhibiting maximum gradients while north-south orientations showing minimum values in the Northern Hemisphere; 4) Notably, the diurnal temperature range exerts greater influence on VTG than solar radiation, potentially challenging the conventional consensus that solar radiation is the dominant factor.

桥梁温度梯度模型对于评估温度效应至关重要，其形状和大小仍然是工程界关注的中心问题。现有的热模拟在计算桥梁与其环境之间的辐射热交换方面存在局限性，特别是在区分阳光照射与阴影地面区域的热贡献方面。为了解决这一差距，本研究创新地开发了一种算法，可以动态跟踪从桥梁表面到地面阴影的辐射视图因子的变化。通过使用一个月的实测天气数据对传统混凝土箱梁进行精细的热分析，主要发现包括：1)垂直温度梯度（VTG）的形状与桥梁设计规范中规定的指数曲线和五阶抛物线最接近，前者的拟合程度略高；2) VTG“零点”点一般发生在梁深1.2 m左右；(3)在3.4°C范围内，桥的方向引起了显著的VTG变化，在北半球，东西方向的梯度最大，而南北方向的梯度最小；4)值得注意的是，日温差对VTG的影响大于太阳辐射，这可能会挑战太阳辐射是主导因素的传统共识。

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引用次数: 0

A rapid slope stability assessment method based on slope size parameters and the slope shape influence factor 基于坡面尺寸参数和坡形影响因子的边坡稳定性快速评价方法

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107502

Huan Liu, Ze Liu

The evaluation of slope stability is an essential part of safe infrastructure design. Still, standard limit-equilibrium methods as well as finite element methods require substantial computational resources and large amounts of soil data to determine slope stability, which is unrealistic for preliminary design and screening of large areas. This paper fills this gap by constructing a geometry-based framework that decouples the effects of slope shape from material properties, enabling quick and accurate stability evaluation. The suggested approach presents the dimensionless slope shape influence (SSI), determined, and an equivalent height (EH) parameter (H). The δ_H∗ relation does not involve any iterative computations, and the δ-H∗ relationship can be expressed physically consistent with the rigorous limit equilibrium theory by taking the factor of safety (FS) as FS = δ × f_std(H∗). The method, implemented in the ICSS-XSlope software, achieves 2.4 % accuracy compared with conventional analyses and runs more than 1000 times faster. Nine case studies demonstrate that it performs very well in validation with numerous limit-equilibrium methods (average errors: 0.41 % vs. Morgenstern-Price and 2.45 % vs. Janbu). The major findings are that groundwater remarkably destabilizes slopes by lowering the three by 26.2 percent under high pore pressure (r u = 0.5) and by 15.5 percent under moderate seismic loading (a w = 0.1). The combined effect of both factors produces compounded stability reduction. The significance of this work lies in providing engineers with a physics-based, geometry-centric tool that bridges empirical design charts and high-fidelity numerical models, making it highly suitable for preliminary design, parametric studies, regional landslide susceptibility mapping, and rapid field assessments where computational resources and detailed soil data are limited.

边坡稳定性评价是基础设施安全设计的重要组成部分。然而，标准的极限平衡法和有限元法需要大量的计算资源和大量的土壤数据来确定边坡的稳定性，这对于大面积的初步设计和筛选是不现实的。本文通过构建一个基于几何的框架来填补这一空白，该框架将斜坡形状的影响与材料特性解耦，从而实现快速准确的稳定性评估。建议的方法给出了无量纲坡度影响（SSI）、确定的和等效高度（EH）参数(H)。δH∗关系不涉及任何迭代计算，δ-H∗关系可以用安全系数FS = δ × f_std（H∗）在物理上符合严格极限平衡理论。该方法在ICSS-XSlope软件中实现，与传统分析相比，准确率达到2.4%，运行速度提高1000倍以上。九个案例研究表明，它在许多极限平衡方法的验证中表现得非常好（平均误差：0.41% vs. Morgenstern-Price, 2.45% vs. Janbu）。主要发现是地下水在高孔隙压力（r u = 0.5）和中等地震荷载（a w = 0.1）下显著降低了26.2%和15.5%的边坡失稳。这两种因素共同作用产生复合稳定性降低。这项工作的意义在于为工程师提供了一个基于物理的、以几何为中心的工具，它将经验设计图表和高保真的数值模型连接起来，使其非常适合于初步设计、参数研究、区域滑坡易感性制图以及计算资源和详细土壤数据有限的快速现场评估。

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引用次数: 0

Model-free real-time MRT temperature inversion: hybrid adaptive differential evolution with local refinement 无模型实时MRT温度反演：局部细化的混合自适应差分进化

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.csite.2025.107594

Kaihua Zhang , Lingling Hua , Yufang Liu

Multispectral Radiation Thermometry (MRT) enables precise non-contact temperature measurement, critical for aerospace thermal protection systems and metal heat treatment monitoring. The underdetermined radiative transfer equation complicates temperature-emissivity decoupling, with traditional methods relying on a priori emissivity assumptions, often leading to systematic errors. To address these limitations, this study proposes a hybrid adaptive differential evolution algorithm with local refinement (HADE-LR), supported by a reference-temperature model that stabilizes the inversion process. Key innovations include: (1) Latin hypercube sampling for initial population construction to optimize parameter space exploration; (2) an adaptive variational-crossover operator to enhance global search efficiency; and (3) a three-stage local optimizer combining Nelder-Mead simplex, L-BFGS-B quasi-Newton, and damped Newton methods for high-precision solutions. Numerical simulations across six emissivity models achieved a maximum temperature relative error of 0.4513 % at 1800 K. Validation on silicon carbide and alloy steel further shows inversion errors below 0.44 % under noise levels up to 5 %, with emissivity curves closely matching measurements. The algorithm operates without emissivity-model assumptions, supports extended emissivity bounds, and achieves real-time performance with an average computation time of 0.14 s. These results highlight the robustness, efficiency, and broad applicability of HADE-LR for high-temperature MRT.

多光谱辐射测温（MRT）能够实现精确的非接触式温度测量，对于航空航天热保护系统和金属热处理监控至关重要。传统的方法依赖于先验的辐射率假设，而欠定的辐射传递方程使温度-发射率解耦变得复杂，常常导致系统误差。为了解决这些局限性，本研究提出了一种带有局部细化的混合自适应差分进化算法（HADE-LR），该算法由一个稳定反演过程的参考温度模型支持。关键创新包括：(1)拉丁超立方体采样用于初始种群构建，优化参数空间探索；(2)自适应变分交叉算子，提高全局搜索效率；(3)结合了高精度解的Nelder-Mead单纯形、L-BFGS-B准牛顿法和阻尼牛顿法的三级局部优化器。6种发射率模型的数值模拟结果表明，在1800k时的最大温度相对误差为0.4513%。在碳化硅和合金钢上的验证进一步表明，在噪声水平高达5%的情况下，反演误差低于0.44%，发射率曲线与测量结果非常吻合。该算法无需假设发射率模型，支持扩展发射率边界，平均计算时间为0.14 s，实现了实时性。这些结果突出了HADE-LR在高温MRT中的鲁棒性、效率和广泛适用性。

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