Case Studies in Thermal Engineering最新文献

{"title":"Thermally induced displacements and post-thermal shear behavior of soil-structure interfaces using a modified triaxial apparatus","authors":"Chunhong Li ,&nbsp;Sunan Cao ,&nbsp;Zhiwei Liu ,&nbsp;Yaohu Hao","doi":"10.1016/j.csite.2025.106454","DOIUrl":"10.1016/j.csite.2025.106454","url":null,"abstract":"<div><div>The mechanical behavior of energy pile–soil interfaces is significantly influenced by temperature variations, especially under cyclic thermal loading. This study presents an experimental investigation using a modified triaxial apparatus to evaluate the thermally induced structural displacement and subsequent shear behavior of sand–structure interfaces under in-service stress conditions, simulated by applying an initial shear stress. Three representative thermal cycles between 6 and 45 °C, two interface roughness conditions (smooth and rough), and two types of vertical loading: constant vertical stress and constant vertical stiffness were applied. The results show that cyclic thermal loading induced irreversible cumulative downward displacement along the shear direction, which tended to stabilize after several cycles. Displacement accumulation increased with temperature amplitude, and rough interfaces exhibited significantly larger value than smooth ones. Thermal displacement was also substantially lower under constant vertical stiffness conditions compared to constant vertical stress. Although peak shear strength remained largely unaffected by thermal cycling, interface shear stiffness increased significantly in all cases. For rough interfaces, this increase in stiffness markedly reduced the displacement required to reach peak shear stress, to approximately 33–80 % of the corresponding value at room temperature. In contrast, this reduction was minimal for smooth interfaces.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106454"},"PeriodicalIF":6.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-field energy release characteristics during shell-encapsulated Al/PTFE energetic powder deflagration reaction","authors":"Enling Tang,&nbsp;Jiameng Hou,&nbsp;Ruizhi Wang,&nbsp;Yafei Han,&nbsp;Chuang Chen,&nbsp;Mengzhou Chang,&nbsp;Kai Guo,&nbsp;Liping He","doi":"10.1016/j.csite.2025.106434","DOIUrl":"10.1016/j.csite.2025.106434","url":null,"abstract":"<div><div>With the evolution of battlefield environments and the shifting nature of mission objectives, there is a growing demand for non-thermal energy release from energetic materials. Characterizing the multi-physical-field response parameters and energy release behaviors of these materials during reaction processes has become critically important. In this study, Al/PTFE mixed energetic powders (26.5 %/73.5 % by mass) were investigated. The heat release of the Al/PTFE energetic powder was measured using an oxygen bomb calorimeter, and a self-constructed multi-field parameter testing system was employed to monitor various response parameters—including overpressure, acoustic signals, light flash, and electromagnetic emissions—during the deflagration of shell-encapsulated Al/PTFE energetic powders under varying charge mass and charge density conditions in a confined environment. The multi-field energy release characteristics were systematically analyzed. Experimental results demonstrated that the shell-encapsulated Al/PTFE energetic powders exhibited distinct multi-field responses. The intensities of overpressure, sound, light flash, and electromagnetic emissions increased with the charge mass but decreased as the charge density increased within the range of 0.6–0.8 g/cm³. The maximum energy released during the combustion reaction reached 14.3284 kJ/g. These findings provide a theoretical foundation for the design, performance optimization, and safety enhancement of high-energy materials, and hold potential application value in military engineering, aerospace propulsion, and disaster prevention systems. Furthermore, they lay the groundwork for future research on the influence of shell material and energetic particle sizes on multi-field energy release behavior.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106434"},"PeriodicalIF":6.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive analysis of key design parameters affecting the efficiency of flat plate solar thermal collectors","authors":"Ekrem Özden ,&nbsp;Mehmet Numan Kaya","doi":"10.1016/j.csite.2025.106458","DOIUrl":"10.1016/j.csite.2025.106458","url":null,"abstract":"<div><div>This study investigates key parameters affecting solar thermal collector efficiency through both simulation and experimental validation. A TRNSYS model was used and validated against experimental data from two solar thermal collectors tested under various conditions, showing strong agreement between predicted and measured values, with a maximum deviation of approximately 4 %. The investigation systematically analyzes key design parameters: flow rate, inlet water temperature, ambient temperature, pipe diameter, absorptance, emissivity, plate-to-glass gap, and insulation materials and thickness. The results indicate that the best performance occurs at flow rates between 175 and 225 kg/h, with a peak efficiency of 81.2 % at 175 kg/h, and ambient temperatures of 30–34 °C, achieving an efficiency of 84.1 % at 34 °C. The absorptance ratio exhibits a linear relationship with collector efficiency, increasing from 48.4 % at 0.60 absorptance to 81.2 % at 0.95 absorptance, while emissivity negatively affects efficiency, showing an 8.3 % reduction when increased from 0.05 to 0.40, but its impact is less significant than the positive effect of absorptance. Furthermore, simulations of various insulation materials with thermal conductivity coefficients ranging from 0.015 to 0.050 W/m·K demonstrated higher efficiencies at greater thicknesses; however, improvements beyond 45 mm were minimal. Finally, a plate-to-glass gap of 13 mm achieved maximum efficiency among tested gaps.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106458"},"PeriodicalIF":6.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of multi-branch fin inserts for improved thermal response in latent heat storage systems: A numerical approach","authors":"Tuqa Abdulrazzaq ,&nbsp;Hussein Togun ,&nbsp;Jasim M. Mahdi ,&nbsp;Hayder I. Mohammed ,&nbsp;Farhan Lafta Rashid ,&nbsp;Abbas Fadhil Khalaf ,&nbsp;Ali E. Anqi ,&nbsp;Abdellatif M. Sadeq","doi":"10.1016/j.csite.2025.106464","DOIUrl":"10.1016/j.csite.2025.106464","url":null,"abstract":"<div><div>Latent heat thermal energy storage (LHTES) offer a promising solution, but the inherently low thermal conductivity of their storage materials, known as phase change materials (PCMs), impedes thermal response rates. This study numerically explores the impact of multi-branch fin configurations on melting and solidification performance in a fixed-volume LHTES system, aiming to optimize the trade-off between increased fin surface area for improved heat transfer and potential flow constraints from excess fins obstructing convective PCM motion. A transient Two-dimensional (2D) model using the enthalpy-porosity approach simulates the phase change of the PCM around cylindrical tube-fin arrangements. Four cases are compared: plain fins, two-branch fins, four-branch fins, and five-branch fins, all with constant total fin volumes. Results show that multi-branch fins initially enhance melting rates due to increased heat transfer area, but declining returns arise beyond a threshold. At 325 K inlet temperature, the PCM with two-branch, three-branch, and four-branch fins melted completely within 60 min versus 90 min for plain fins, reducing melting time by 33.9 %, 37.1 %, and 44.9 %, respectively. However, the five-branch case provided marginal further improvement due to excessive fin crowding restricting molten PCM flow. Similar trends occurred during solidification, with multi-branch fins reducing solidification times by 18.3–29.0 %. This work guides identifying an optimal fin configuration that balances heat transfer enhancement and unimpeded convection. This approach prevents diminishing returns typically observed when implementing excessive fin volume arrangements.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106464"},"PeriodicalIF":6.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the impact of intermittent heating control strategy system on greenhouse thermal environment","authors":"Mingzhi Zhao, Yingjie Liu, Zheng Han, Chun Chang, Daorina Bao, Rasakhodzhaev Bakhramzhan Sabirovich, Akhadou Jobir","doi":"10.1016/j.csite.2025.106451","DOIUrl":"https://doi.org/10.1016/j.csite.2025.106451","url":null,"abstract":"The heating imbalance in solar-powered heating greenhouses (SHG) severely constrains both energy supply efficiency and crop yield. This study proposes the principle of Thermal Intermittent Heating (TIH), unveiling the differentiated regulatory mechanisms by which the duty cycle (&lt;mml:math altimg=\"si1.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:mo linebreak=\"goodbreak\" linebreakstyle=\"after\"&gt;∅&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;) governs thermal dynamics in both aerial greenhouse environments and subsurface soil layers. Under the greenhouse thermal environment conditions, the operational mode with &lt;mml:math altimg=\"si1.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:mo linebreak=\"goodbreak\" linebreakstyle=\"after\"&gt;∅&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; = 0.67 (control scheme (2,1)) demonstrates optimal thermal stratification adaptation through an 8-h heating/4-h intermittent cycle. This configuration achieved the highest Comprehensive Energy Energy Efficiency Index (COP) of 88.7 % in the fourth layer (group maximum), along with minimal thermal fluctuations indicated by &lt;mml:math altimg=\"si2.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;σ&lt;/mml:mi&gt;&lt;mml:mi&gt;T&lt;/mml:mi&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; (2.82 °C) and &lt;mml:math altimg=\"si3.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;C&lt;/mml:mi&gt;&lt;mml:mi&gt;V&lt;/mml:mi&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; (11.12 %). The strategy effectively compensates for thermal dissipation in upper zones caused by buoyant airflow (48 % elevation in mean temperature), while preventing excessive top-layer overheating observed in continuous heating (&lt;mml:math altimg=\"si1.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:mo linebreak=\"goodbreak\" linebreakstyle=\"after\"&gt;∅&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; = 1) scenarios, which exhibited 128 % surge in &lt;mml:math altimg=\"si2.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;σ&lt;/mml:mi&gt;&lt;mml:mi&gt;T&lt;/mml:mi&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;. Within the soil layer (0.1–0.2m depth), this &lt;mml:math altimg=\"si1.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:mo linebreak=\"goodbreak\" linebreakstyle=\"after\"&gt;∅&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; value synchronously optimizes thermal penetration intensity and stability: The first-layer COP reached 182.39 (&lt;mml:math altimg=\"si4.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:mover accent=\"true\"&gt;&lt;mml:mi&gt;T&lt;/mml:mi&gt;&lt;mml:mo&gt;‾&lt;/mml:mo&gt;&lt;/mml:mover&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; = 19.72 °C) with &lt;mml:math altimg=\"si2.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;σ&lt;/mml:mi&gt;&lt;mml:mi&gt;T&lt;/mml:mi&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; merely 1.85 °C, where heating duration precisely matched the soil's thermal diffusion period (6–8 h). Whereas &lt;mml:math altimg=\"si1.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:mo linebreak=\"goodbreak\" linebreakstyle=\"after\"&gt;∅&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; = 1 induced 197 % surge in soil &lt;mml:math altimg=\"si2.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;σ&lt;/mml:mi&gt;&lt;mml:mi&gt;T&lt;/mml:mi&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; (5.51 °C vs. optimal condition), and &lt;mml:math altimg=\"si1.svg\"&gt;&lt;mml:mrow&gt;&lt;mml:mo linebreak=\"goodbreak\" linebreakstyle=\"after\"&gt;∅&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt; = 0.13 resulted in 22.6 % reduction in deep-layer temperature mean. The study demonstrates COP's capacity to quantify heter","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"51 1","pages":"106451"},"PeriodicalIF":6.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144289811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A calibration procedure for simulation models of rural residential buildings using monthly energy bills: A case study in Zhejiang, China","authors":"Yuanyuan Wei ,&nbsp;Song He ,&nbsp;Ping Huang ,&nbsp;Yuechen Duan ,&nbsp;Bart Julien Dewancker ,&nbsp;Luyao Zhou","doi":"10.1016/j.csite.2025.106463","DOIUrl":"10.1016/j.csite.2025.106463","url":null,"abstract":"<div><div>Building energy simulation (BES) is crucial for planning energy-efficient retrofits in rural Chinese residences, yet its accuracy is often limited by insufficient calibration data. This study develops a practical and efficient model calibration procedure that combines monthly electricity bills with a multi-objective genetic algorithm to improve BES reliability under low-data conditions. A case study on a typical rural dwelling in Zhejiang Province was conducted. Nine key parameters—relating to envelope performance, equipment efficiency, and heating schedules—were selected to capture major modeling uncertainties. Calibration followed ASHRAE Guideline 14, targeting a Normalized Mean Bias Error (NMBE) of ≤5 % and a Coefficient of Variation of the Root Mean Square Error (CV(RMSE)) of ≤15 %. Results showed that NMBE was reduced from 12.775 % to 0.108 %, and CV(RMSE) from 21.294 % to 11.054 %, confirming the procedure's effectiveness. The proposed approach enables accurate BES calibration using low-resolution data, bridging the gap between limited field data and the need for reliable energy modeling. It offers a scalable, cost-effective solution to support large-scale retrofit planning in rural settings.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106463"},"PeriodicalIF":6.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy-economy analysis of a novel spiral channeled conical turbulator inserted within the parabolic trough solar collector absorber tube","authors":"Sarminah Samad ,&nbsp;Salman Saeidlou ,&nbsp;Ibrahim Mahariq ,&nbsp;Naoufel Kraiem ,&nbsp;Ali Alamry ,&nbsp;Priya A. Hoskeri ,&nbsp;S.P. Ghoushchi","doi":"10.1016/j.csite.2025.106462","DOIUrl":"10.1016/j.csite.2025.106462","url":null,"abstract":"<div><div>This study introduces a novel spiral channeled conical turbulator (SCCT) to enhance the hydrothermal and economic performance of a parabolic trough solar collector. Key design parameters, including spiral channel width (1–3 mm) and pitch (1–9 mm), are investigated, and the results are compared to those of a plain conical turbulator (PCT) and plain absorber tube. The inclined surfaces of the PCT and SCCT induce a strong radial flow, significantly improving heat transfer. Heat transfer and friction coefficients exhibit a direct correlation with spiral channel pitch but an inverse relationship with channel width. The PCT achieves the highest heat transfer enhancement, up to 550 % over a plain tube. However, the SCCT's aerodynamic geometry, enabled by its spiral channels, reduces pressure drop, yielding a higher and optimal performance evaluation criterion (PEC) compared to the PCT. The SCCT achieves a maximum PEC of 3.05 at a channel pitch of 5 mm and a width of 3 mm. This results in a 375 % improvement in heat transfer and a 280 % increase in the friction coefficient compared to plain absorber tubes. Economically, the PCT outperforms, with a levelized cost of energy (LCOE) of 0.405$/kWh and a payback time of 2.7 years. These results indicate that PCT is the optimal choice for heat transfer and economic performance, while SCCT is superior from a hydrothermal perspective.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106462"},"PeriodicalIF":6.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144254449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study on combustion process of hydrogenated catalytical biodiesel sprays under methanol-air premixed atmosphere","authors":"Wenli Gao ,&nbsp;Guojia Jia ,&nbsp;Tiemin Xuan ,&nbsp;Zhixia He","doi":"10.1016/j.csite.2025.106461","DOIUrl":"10.1016/j.csite.2025.106461","url":null,"abstract":"<div><div>Methanol's low reactivity impedes its application as a renewable fuel in compression-ignition (CI) engines. This study investigates the viability of methanol as a low-reactivity fuel (LRF) in hydrogenated catalytic biodiesel (HCB)-assisted dual-fuel (DF) combustion under reactivity-controlled compression ignition (RCCI) conditions. Using Reynolds-Averaged Navier–Stokes (RANS) simulations, the effects of varying methanol concentrations on ignition characteristics and flame structure are quantified. The results reveal that both single-fuel (SF) and DF spray combustion exhibit a two-stage ignition process, though this phenomenon is weaker in SF combustion. Moreover, ambient methanol and temperature variations significantly influence both low- and high-temperature combustion. The sensitivity of low-temperature combustion decreases once the premixed methanol equivalence ratio (<span><math><mrow><msub><mi>φ</mi><mi>m</mi></msub></mrow></math></span>) reaches 0.5, whereas the induction time continues to increase with higher methanol content. Additionally, the flame kernel location and peak heat-release rate are closely linked to regions of maximal formaldehyde (CH₂O) consumption. Following HCB injection cessation, high-temperature combustion, characterized by rapid CH₂O depletion, dominates the spray interior. In DF operation, substantial premixed methanol combustion occurs, with OH and C₂H₂ diffusing into fuel-lean zones. These insights into HCB-methanol RCCI interactions inform optimization of operational parameters for controlled ignition and efficient energy release, advancing methanol's viability as a clean CI engine fuel.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106461"},"PeriodicalIF":6.4,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study of a cool roof and double-glazing window coupled to an air-cavity under a tropical Mexican climate","authors":"Y. Olazo-Gómez ,&nbsp;I. Hernández-López ,&nbsp;I. Zavala-Guillén ,&nbsp;I. Hernández-Pérez ,&nbsp;D. García-Pérez","doi":"10.1016/j.csite.2025.106372","DOIUrl":"10.1016/j.csite.2025.106372","url":null,"abstract":"<div><div>This research presents a numerical study of the conjugate heat transfer in an air cavity with a concrete slab roof and a window on the east facade. We considered three different window configurations: a single clear glass window (C1), a double clear glass window (C2), and a double glass window with an inner clear glass and an outer reflective glass (C3), as well as three different types of roofs: gray roof, white roof, and black roof. Because both the conventional windows and roofs show high thermal energy gains that increase the energy dependence associated with using air conditioning equipment in buildings in tropical climates, we compared all cases regarding heat gains and temperature obtained under tropical weather conditions of Merida, Yucatan, Mexico. The results showed that WR is the option with the lowest temperature value at the inner surface of the roof (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>R</mi><mo>,</mo><mi>i</mi><mi>n</mi></mrow></msub></math></span> <span><math><mrow><mo>&lt;</mo><mn>39</mn></mrow></math></span> <!--> <!-->°C). In addition, the C3-WR configuration reduced energy transmission through the facades by up to 5693.1 Wh, prevented the emission of 74.3 kg of CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>, and lowered electricity consumption costs by 13.2 USD/kWh compared to the C1-GR base case on the warmest day.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106372"},"PeriodicalIF":6.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical investigation on thermal efficiency and resistance of high-temperature thermosiphons using dimensionless method","authors":"Haojie Zhang ,&nbsp;Zhuqian Zhang ,&nbsp;Lixin Yang ,&nbsp;Yueyi Li ,&nbsp;Heyao Li ,&nbsp;Yuchen Zhou","doi":"10.1016/j.csite.2025.106391","DOIUrl":"10.1016/j.csite.2025.106391","url":null,"abstract":"<div><div>Exploring the thermal characteristics of high-temperature heat pipes (HTHPs) requires a detailed analysis of how each parameter affects their heat transfer efficiency. The hydrodynamic and thermophysical properties of working fluids flow are related to structural parameters of HTHPs, and some variables are combined into dimensionless numbers by means of rational physical relationships. Analyzing the thermal behavior of HTHPs using dimensionless numbers provides certain advantages over a straightforward parametric approach. In this study, a theoretical model of the high-temperature thermosiphon (HTT) is developed based on the heat transfer mechanisms inherent in its operation. By establishing differential equations and substituting some experimental data, the numerical calculation is made in the MATLAB codes. The computational results are utilized to assess the influence of the length-diameter ratio, Bond number, and Jakob number on the thermal performance of the HTTs. The correlation between the structural and thermophysical characteristics of HTTs is ascertained by investigating the circulation of working fluid. Utilizing this correlation, three dimensionless numbers M₁, M₂, and M₃ are derived. The effect of these dimensionless numbers on the thermal performance is further clarified by the computational analysis. It is found that three dimensionless numbers are effective for guiding the analysis of the thermal performance, a smaller M₃ number contributes to enhancing the heat transfer efficiency of the HTTs.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"73 ","pages":"Article 106391"},"PeriodicalIF":6.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144254604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}