Case Studies in Thermal Engineering最新文献

{"title":"Intelligent graphene-integrated solar thermal absorber: Artificial intelligence-driven discovery of a high-efficiency petal architecture for renewable energy applications","authors":"Abdulkarem H.M. Almawgani, Abdulrhman Alshaabani, Bo Bo Han, Mohamad A. Alawad, Ashish Baldania, Tabish Ali Fatihi, Yogesh Sharma, Shobhit K. Patel","doi":"10.1016/j.csite.2026.108031","DOIUrl":"https://doi.org/10.1016/j.csite.2026.108031","url":null,"abstract":"With the continuously increasing power demand across modern electrical and industrial systems, the development of efficient power supplementation technologies has become essential. This research presents a novel machine-learning-optimized solar absorber designed for advanced renewable energy applications. The proposed absorber features a petal-shaped geometry with a multilayer configuration composed of Chromium (Cr), Gallium Arsenide (GaAs), and Tin Nitride (TiN). Broadband solar absorption performance is evaluated through detailed bandwidth analysis, revealing a peak absorption of 98.68% at 700 nm and an average absorption of 92.67% across a wide spectral range extending up to 2800 nm (overall rate). Furthermore, the absorber demonstrates strong polarization insensitivity, ensuring stable performance under varying incident angles and across atmospheric regions from ultraviolet to near-infrared (UV–NIR). Machine learning techniques are employed to optimize the structural parameters, achieving a high optimization efficiency of 0.99. Owing to its broadband absorption, polarization-independent behavior, and high efficiency, the proposed solar absorber is well suited for renewable energy harvesting and industrial heating applications.","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"19 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147681294","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 of microwave heating and scale-up challenges in dielectric reactor systems","authors":"Jaedeuk Park, Seolha Lim, Yunseo Cho, Sunil Kwon, Ji Hoon Park, Young-Woo You, Jin Hee Lee","doi":"10.1016/j.csite.2026.108027","DOIUrl":"https://doi.org/10.1016/j.csite.2026.108027","url":null,"abstract":"","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"4 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147619878","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":"Effect of Cooling Rate on Pore Structure and Mechanical Properties of Shale Wellbore during Formation Heat Exchange Driven by Drilling Fluid Circulation","authors":"Wangji Ding, Jiakun Guo, Haicheng She","doi":"10.1016/j.csite.2026.108023","DOIUrl":"https://doi.org/10.1016/j.csite.2026.108023","url":null,"abstract":"To reveal the thermal shock damage mechanism and influence law of cooling rate on the pore structure and mechanical properties of shale wellbore induced by drilling fluid circulation during formation heat exchange process, a drilling fluid circulation temperature transfer model was established to quantify the cooling rate characteristics under different well depths and circulation times. Then, the shale samples were subjected to variable cooling rate heat treatment in an intelligent high-temperature furnace. The microscopic pore evolution and mechanical property deterioration were analyzed by combining SEM, NMR and triaxial compression tests. The results show that: (1) SEM image processing combined with pore morphological parameters enables the classification of pores and fractures as well as the quantification of porosity; (2) NMR-based <ce:italic>T</ce:italic><ce:inf loc=\"post\">2</ce:inf>-pore radius conversion and spectral area comparison established a correlation model for pore volume and expansion rate characterization; (3) A higher cooling rate results in a increased pore volume, a greater number of strip-shaped fractures, and accelerated transformation of micro-mesopores to macropores (with a weak thermal expansion effect). Meanwhile, higher porosity triggers more severe deterioration of shale shear strength and elastic modulus, accompanied by faster propagation of micro-mesoscopic fractures; (4) A statistical damage model with the expansion rate as the damage variable is established, and a corresponding shale statistical damage constitutive model is further developed. The predicted values are in good agreement with the experimental results, which can effectively quantify the evolution law of mechanical damage, and provide key theoretical models and calculation method support for the prediction of thermal shock damage of shale wellbore under the drilling fluid circulation condition in deep engineering.","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"276 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147630024","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":"Reduction of the HVAC system size in School Buildings through Earth-to-Air Heat Exchangers (EAHE)","authors":"D. D’Agostino, N. Kouki, F. Minelli, F. Minichiello, A. Vityi","doi":"10.1016/j.csite.2026.108025","DOIUrl":"https://doi.org/10.1016/j.csite.2026.108025","url":null,"abstract":"","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"2 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147619879","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-objective optimization and numerical analysis of ammonia-diesel dual-fuel engine combustion and emissions based on RSM-NSGA-Ⅲ-TOPSIS approach","authors":"Dongli Tan, Zhaoyang Li, Guangyu Ma, Mingzhang Pan, Zibin Yin, Yixue Sun, Zhaoxiong Chen, Jiangde Lin, Zhiqing Zhang","doi":"10.1016/j.csite.2026.107996","DOIUrl":"https://doi.org/10.1016/j.csite.2026.107996","url":null,"abstract":"","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"22 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2026-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147598083","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":"Failure probability model for LPG spherical tanks under multi-pool fire coupling","authors":"Jie Wang ,&nbsp;Mingguang Zhang ,&nbsp;Xudong Yang ,&nbsp;Zhen Miao ,&nbsp;Zequan Zhu ,&nbsp;Shuang Wang ,&nbsp;Xingmin Cui","doi":"10.1016/j.csite.2026.107921","DOIUrl":"10.1016/j.csite.2026.107921","url":null,"abstract":"<div><div>Pressurized spherical tanks in chemical industrial parks represent high-risk nodes due to their high-energy contents and susceptibility to catastrophic domino effects. However, the synergistic thermal-mechanical response of these tanks under multiple-pool fire coupling remains insufficiently characterized, posing significant challenges for quantitative risk assessment. In this paper, statistics on typical accidents and probabilistic event tree analysis were utilized to investigate potential domino accident pathways for LPG spherical tanks. The results indicate that leakage is the predominant initiating event, with fire serving as the primary catalyst for escalation, resulting in an average accident chain length of 1.18. To address the lack of failure criteria for thermal radiation coupling, an isosceles triangle layout was established to simulate the thermal response of tanks (1000–5000 m³) under both single and coupled fire conditions. The simulations reveal that structural failure is consistently initiated at the gas-liquid interface due to localized thermal softening. While thermal radiation coupling significantly accelerates the failure sequence, larger tanks exhibit higher thermal inertia, which delays internal pressurization and extends the safety window. The failure time criteria and a failure probability model were developed. Validation results confirm a model deviation of less than 6%, demonstrating better predictive accuracy compared to traditional models and providing a robust, conservative baseline for the safety management of LPG spherical tanks.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"80 ","pages":"Article 107921"},"PeriodicalIF":6.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387424","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-efficient optimization of radiant floor heating systems via random forest-based surrogate models and evolutionary algorithms","authors":"Erkan Sami Kokten ,&nbsp;Mutlu Tekir","doi":"10.1016/j.csite.2026.107931","DOIUrl":"10.1016/j.csite.2026.107931","url":null,"abstract":"<div><div>Radiant floor heating systems (RFHS) are among the modern heating solutions that provide high energy efficiency and thermal comfort due to their low-temperature operating principle. However, in systems using flooring materials such as wood and laminate flooring, numerous design and operational parameters can influence surface temperature and heat flux. This makes system design a complex optimization problem. In this study, an integrated optimization approach has been developed to increase the energy efficiency of RFHS with parquet flooring, minimizing surface heat flux while also meeting thermal comfort and material safety constraints. First, ANSYS-based thermal analyses were conducted for various water temperatures, ambient temperatures, pipe spacing, parquet thickness, and material thermal conductivity values, resulting in a comprehensive dataset. Using the numerical data obtained, Random Forest (RF) based predictive models capable of accurately estimating surface temperature and surface heat flux were developed. The trained RF models were integrated with a Genetic Algorithm (GA) to solve a highly constrained optimization problem. The results obtained showed that the flooring material has a decisive effect on system performance. Furthermore, considering that theoretically optimal solutions providing very low heat flux could lead to slow heating problems in practice, a scenario analysis was conducted based on the water temperature-ambient temperature difference. The scenario analysis results revealed that this temperature difference is a critical balancing parameter between the system's heating response and energy consumption. Thus, the study offers a comprehensive decision support framework that evaluates not only theoretical optimums but also practical operating conditions. The developed Random Forest-based surrogate model demonstrated high predictive accuracy with an R² value of 0.992 and a Mean Absolute Percentage Error (MAPE) value of 4.21%. Furthermore, the model's robustness was validated against unseen literature data, yielding a high R² value of 0.985. Scenario-based optimization results indicated that, under defined constraints, heat flux values varied between approximately 1 W/m² and 110 W/m² depending on the temperature difference between the heating water and the ambient environment. Multi-run robustness analysis confirmed 100% feasibility and stable convergence of the RF-GA framework, while comparison with Random Search highlighted substantial gains in computational efficiency and constraint satisfaction. Consequently, this study combines ANSYS-based numerical analyses, machine learning-supported predictive models, and evolutionary optimization techniques to propose a rapid, reliable, and energy-focused design approach for parquet-covered radiant heating systems.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"80 ","pages":"Article 107931"},"PeriodicalIF":6.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387430","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":"Aerodynamic characteristics of CMC turbine blades under diverse surface features and inlet conditions","authors":"Dewei Zhang ,&nbsp;Mingdong Zhao ,&nbsp;Zheng Wang ,&nbsp;Longfei Wang ,&nbsp;Junkui Mao ,&nbsp;Yimin Li ,&nbsp;Xuejian Zhu","doi":"10.1016/j.csite.2026.107926","DOIUrl":"10.1016/j.csite.2026.107926","url":null,"abstract":"<div><div>The paper investigates the aerodynamic characteristics of turbine blades with three different surface features under five attack angles and three outlet Mach numbers (<em>Ma</em>) through experimental and simulation approaches. It has been discovered that the surfaces of ceramic matrix composite (CMC) blades fabricated via a specific process and those of ordinary metal blades are extremely smooth, with an exceedingly small difference in surface roughness, leading to a high level of consistency in surface static pressure distributions. For the texture blade, however, the pressure difference between the pressure side and suction side is significantly reduced. At attack angles of 0°, 7°, and 15°, cascade outlet's average total pressure loss coefficients for the texture blade are 7.5% and 13.2%, 7.1% and 6.4%, and 5.1% and 9.2% higher than those of the CMC and metal blades, respectively. This is attributed to the continuous interaction between the airflow and texture features, which disrupts the boundary layer flow, induces vortices, and exacerbates flow losses. Additionally, three types of blades show similar distributions of total pressure loss coefficient along the blade height. For the CMC blade, a larger positive attack angle increases the surface pressure difference and total pressure loss coefficient, whereas a larger negative attack angle produces the opposite effect. The research further confirms that the CMC blade processed by the specified technology demonstrates excellent aerodynamic performance, characterized by a low overall total pressure loss coefficient under high <em>Ma</em> conditions.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"80 ","pages":"Article 107926"},"PeriodicalIF":6.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387460","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":"CFD-guided thermodynamic evaluation of zeotropic mixtures in vertical channels for sustainable heat pump systems","authors":"Zongguo Xue ,&nbsp;Jierong Liang ,&nbsp;Wilko Rohlfs ,&nbsp;Yunfei Yan ,&nbsp;Chenghua Zhang ,&nbsp;Yonghong Wu ,&nbsp;Tingting Zhu","doi":"10.1016/j.csite.2026.107840","DOIUrl":"10.1016/j.csite.2026.107840","url":null,"abstract":"<div><div>Zeotropic refrigerant mixtures are pivotal for decarbonizing heat pump technologies, particularly in emerging district heating applications, due to their compositional versatility and temperature glide characteristics. However, their complex interfacial behavior, transport properties, and flow dynamics lead to scarce data on evaporator performance and heat transfer coefficients, hindering optimal system design. This work investigates the thermodynamic performance of zeotropic mixture refrigerants (CO₂/R290, R600/R290, R32/R1234yf, and R1234yf/R1234ze(Z)) in a vertical plate evaporator using computational fluid dynamics (CFD) simulations and experimental validation. Innovatively employing the Volume of Fluid (VOF) method coupled with the Lee phase change model, the CFD framework successfully captured the intricate multiphase flow and evaporation phenomena of diverse mixtures within microscale channels. Results demonstrate that a pinch point temperature difference (PPTD) of ∼4 K achieves optimal heat transfer efficiency. Crucially, CO₂/R290 exhibited superior performance, achieving a total heat transfer coefficient of ∼9.61 kW/m²K, which is significantly higher (up to ∼64%) than mixtures like R1234yf/R1234ze(Z) (∼5.85 kW/m² K). Active modulation of water mass flow rates (1.62–3.24 kg/h) effectively compensated for refrigerant-specific limitations, achieving consistent cooling capacities ranging from 29.77 W to 55.83 W across all tested mixtures under the target PPTD. The findings, particularly the outstanding heat transfer characteristics and uniform temperature distribution of CO₂/R290, emphasize its strong potential as a high-performance candidate for next-generation sustainable heat pump systems. This work underscores the critical role of thermophysical properties and operational parameter optimization in enhancing heat pump efficiency.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"80 ","pages":"Article 107840"},"PeriodicalIF":6.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146777428","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":"CFD-based optimization of aperture geometry for reducing forced convection losses in a cylindrical cavity receiver of a dish/stirling system","authors":"André Leandro de Souza ,&nbsp;Luis Sebastian Mendoza Castellanos ,&nbsp;Gaylord Enrique Carrillo Caballero ,&nbsp;Ana Lisbeth Galindo Noguera ,&nbsp;Osvaldo José Venturini ,&nbsp;Vladimir Rafael Melian Cobas ,&nbsp;Electo Eduardo Silva Lora","doi":"10.1016/j.csite.2026.107836","DOIUrl":"10.1016/j.csite.2026.107836","url":null,"abstract":"<div><div>Convective heat losses due to airflow recirculation at the cavity aperture are among the main efficiency limitations of Dish/Stirling solar receivers. While previous studies have primarily focused on internal modifications or advanced working fluids to mitigate thermal losses, the aerodynamic role of the cavity opening region has received comparatively limited attention. In this study, a numerical investigation using Computational Fluid Dynamics (CFD) is conducted to analyze the influence of receiver inclination on airflow behavior and to evaluate geometric modifications to the aperture of a cylindrical cavity receiver used in a commercial Parabolic Dish Concentrator (PDC–Trinum®) system. Simulations were performed under the climatic conditions of Itajubá–MG (Brazil) for receiver inclinations ranging from 0° to 90°, considering four different aperture geometry configurations. The results show that airflow recirculation intensity is strongly dependent on receiver inclination and can be significantly reduced through appropriate aperture design. Among the proposed configurations, a torus-like geometry applied at the cavity opening achieved the best aerodynamic performance, reducing internal air recirculation by up to 95.6%, depending on the inclination angle. When the velocities obtained through the CFD analysis were used as inputs to the mathematical heat-transfer model, the results indicate a potential reduction of approximately 96% in forced convection losses compared to the original receiver. The findings demonstrate that aerodynamic optimization of the cavity aperture is an effective and low-complexity strategy for enhancing the thermal performance of Dish/Stirling receivers.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"80 ","pages":"Article 107836"},"PeriodicalIF":6.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146777437","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}