Case Studies in Thermal Engineering最新文献

{"title":"Simultaneous multi-objective optimization of a biogas-based power generation and brine desalination system for using in sport facilities","authors":"Li Fan ,&nbsp;Zhanguo Su","doi":"10.1016/j.csite.2025.105958","DOIUrl":"10.1016/j.csite.2025.105958","url":null,"abstract":"<div><div>The increasing global demand for sustainable energy and potable water necessitates efficient energy conversion technologies. Co-generation systems, which simultaneously produce electricity and desalinated water, represent a promising solution for fulfilling the essential needs of urban areas and localized facilities, such as sports complexes. This study evaluates a co-generation system designed to provide energy and potable water for a specific sports complex. The thermodynamic cycle was simulated utilizing validated numerical methods, solving the governing equations governing the system's operation. Multi-objective optimization, based on the Pareto Front methodology, was implemented to enhance overall system performance and minimize environmental impact. A comprehensive life cycle environmental assessment was performed using exergo-environmental analysis. Baseline simulations indicated a power output of 1441 kW, alongside a desalinated water production rate of 1.392 m³/h. These values correspond to an initial energy efficiency of 71.8 % and an exergy efficiency of 41.64 %. Following the multi-objective optimization procedure, guided by the Pareto Front, the system performance was notably improved. The energy efficiency increased to 72.13 %, and the exergy efficiency reached 44.92 %. Furthermore, the exergo-environmental (Ɛes) exhibited a marked improvement, achieving a value of 0.964, signifying a reduced environmental burden. The results underscore the potential of optimized co-generation systems to enhance energy efficiency and sustainability<strong>.</strong></div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"69 ","pages":"Article 105958"},"PeriodicalIF":6.4,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of premixed swirl-stabilized flame on the cooling performance of an effusion-cooled combustor liner","authors":"Xiang Lu ,&nbsp;Yongbin Ji ,&nbsp;Bing Ge ,&nbsp;Shusheng Zang","doi":"10.1016/j.csite.2025.105938","DOIUrl":"10.1016/j.csite.2025.105938","url":null,"abstract":"<div><div>The impact of premixed swirl-stabilized flame on the cooling performance of an effusion-cooled combustor liner perforated by cylindrical and fan-shaped holes is investigated under varying blowing ratios. Infrared technology is employed to ascertain the wall temperature, and computations are performed to elucidate the interaction mechanism between the flame and the cooling jets. The results demonstrate that since the premixed flame has not yet burnt out before impinging on the wall, the mainstream near the wall contains low-temperature mixtures in the swirl impingement zone and high-temperature gas in the corner recirculation and liner tail. Consequently, the wall temperature in the swirl impingement zone is relatively low, while the cooling effectiveness is high. Conversely, the corner circulation zone and the tail of the liner exhibit reduced cooling effectiveness. The increase in the blowing ratios has a negligible influence on the cooling effectiveness distribution but can enhance the cooling effectiveness and its uniformity. The fan-shaped holes are similar in the distribution of cooling effectiveness to the cylindrical ones but higher in value. Meanwhile, they have better uniformity of cooling effectiveness than the cylindrical holes, as more cooling air is assigned to holes in the corner recirculation zone and liner tail where cooling effectiveness is lower.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105938"},"PeriodicalIF":6.4,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal performance of condensation phase change in the shell side of discontinuous helical baffle heat exchanger","authors":"Zhengfeng Shuai ,&nbsp;Xiandao Lei ,&nbsp;Dianhui Ge ,&nbsp;Yajun Shen ,&nbsp;Junfeng Zhang ,&nbsp;Rui Guo ,&nbsp;Yiran Duan ,&nbsp;Yueshe Wang","doi":"10.1016/j.csite.2025.105959","DOIUrl":"10.1016/j.csite.2025.105959","url":null,"abstract":"<div><div>The discontinuous helical baffle heat exchanger is widely used in industrial applications due to its high heat transfer efficiency and uniform flow distribution. This study, focused on the recovery of the waste heat from steam condensation in power plants, establishes a three-dimensional geometric model of a discontinuous helical baffle heat exchanger and numerically simulates the condensation process within the shell side of the heat exchanger using Ansys Fluent 2020R1. The characteristics of flow and temperature fields is analyzed and the effects of steam inlet temperature, steam inlet velocity, and cooling water inlet velocity on the condensation performance of shell side are investigated. The results indicate that, with a constant cooling water velocity in the tube side, the heat transfer coefficient in the shell side increases with rising steam inlet velocity and decreases with increasing superheat degree of the steam. When steam inlet velocity increases from 5 m∙s⁻¹ to 20 m∙s⁻¹, the shell-side heat transfer coefficient increases by 81.22 % on average. When steam inlet velocity is 20 m∙s⁻¹, as steam inlet superheat increases from 10 K to 50 K, the shell-side heat transfer coefficient decreases by 16.69 %. This study provides scientific support for further research on discontinuous helical baffle heat exchangers.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105959"},"PeriodicalIF":6.4,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal performance evaluation of recycled salt hydrates through T-history","authors":"Charles A. Wesemann ,&nbsp;Tessa Junggeburth ,&nbsp;H.J.H. Brouwers","doi":"10.1016/j.csite.2025.105961","DOIUrl":"10.1016/j.csite.2025.105961","url":null,"abstract":"<div><div>Recycled magnesium sulfate heptahydrate, sourced from chemical byproducts in the nano-silica extraction from olivine, exhibits unique minor phases and reduced purity compared to analytical-grade counterparts. This study investigates phase stabilizer usage, titania as a nucleating agent, and carboxymethyl cellulose (CMC) as a stabilizing gel, to enhance the functionality of recycled salt hydrates for thermal energy storage applications. Thermocouple measurements over ten heating and cooling cycles reveal distinct thermal characteristics, with observable latent heat manifesting as a critical indicator for melting-crystallization cycling. The addition of titania increases the number of functional cycles of recycled samples but diminishes performance in analytical samples. Suggesting it provides another function other than nucleation. Statistical analysis shows an exponential decay in thermal cycles (R² &gt; 0.84) with increased cycles. While titania shows promise, gel stabilizers like CMC did not yield meaningful results. The average latent heat storage of the recycled epsomite was 285.4 ± 37.1 J/g. This study addresses a previously unexplored area and highlights the potential of nucleating agents in improving the functionality of recycled salt hydrates for sustainable thermal energy storage.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105961"},"PeriodicalIF":6.4,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal management of turbine disc cavity system using FFBPNN and NSGA II algorithm","authors":"Zhenzong He ,&nbsp;Shuang Liang ,&nbsp;Junkui Mao ,&nbsp;Weiwei Zhao ,&nbsp;Min Zuo ,&nbsp;Yao Fu","doi":"10.1016/j.csite.2025.105954","DOIUrl":"10.1016/j.csite.2025.105954","url":null,"abstract":"<div><div>This study addresses the thermal management of the turbine disc cavity system (TDCS) by combining the feed-forward backward propagation neural network (FFBPNN) with the non-dominated sorting genetic algorithm II (NSGA II). First, the heat transfer analysis of the TDCS is carried out using the cross-scale computational model which is consist of 1D fluid network method and the 2D finite element method. The impact of different cooling air inlet conditions on the heat transfer performance of the TDCS is investigated. Results show that changing the inlet pressure and temperature significantly affects the heat transfer performance of the TDCS, and the TDCS temperature field can be regulated by the inlet parameters. Then, the prediction model based on the FFBPNN is established to predict the heat transfer performance of the TDCS, and satisfactory result is obtained with mean relative error lower than 1.5 % and a coefficient of determination higher than 0.998. Finally, the NSGA II is employed to optimize the cool air inlet condition to achieve thermal management of the TDCS. The Pareto solution set and the optimal solution are obtained. The results indicate that the most comprehensive improvement in the heat transfer performance of the TDCS can be achieved by present technology.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105954"},"PeriodicalIF":6.4,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on the effect of thermosensitive controlled-release inhibitor on coal spontaneous combustion","authors":"Shengli Guo ,&nbsp;Weile Geng ,&nbsp;Shujie Yuan ,&nbsp;Xiaoxue Xu ,&nbsp;Shuwen Zhang ,&nbsp;Qingguo Ren ,&nbsp;Chengli Liu","doi":"10.1016/j.csite.2025.105955","DOIUrl":"10.1016/j.csite.2025.105955","url":null,"abstract":"<div><div>Inhibitors are widely used on-site due to their effective prevention. The effect of a novel compound inhibitor composed of thermosensitive hydrogel (TSH) and antioxidants (tea polyphenols (TP) and L-ascorbic acid (VC)) on coal spontaneous combustion (CSC) characteristics was studied. Its inhibitory effect was compared with that of the single component or MgCl₂ by macroscopic and microscopic tests. The results show that the release of CO or CO₂ from coal treated with inhibitors during temperature-programmed tests was reduced, and the crossing-point temperature of TSH-TP/VC-treated coal increased by 21.4 °C. The content of –CH₂, –CH₃ and oxygen-containing group in inhibitor-treated coal decreased than before, the characteristic temperature of spontaneous combustion increased significantly, and the mass gain values of coal treated with TSH-TP/VC, TSH, TP/VC or MgCl₂ decreased by 0.99 %, 0.93 %, 0.87 %, 0.24 %, respectively. The inhibitory efficacy of TSH-TP/VC is superior to the effect of single component or traditional inhibitor MgCl₂, and it is effective in inhibiting the entire oxidative decomposition and combustion stage of coal. TSH can effectively cover the coal body and remove the accumulated heat. At the same time, TP/VC hinders the emergence of free radicals and chelates with metal ions, thereby exhibiting a significant suppression of CSC.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105955"},"PeriodicalIF":6.4,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143508863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metallic magnetic calorimeters based on quantum metrology: Optimal design of thermal coupling system","authors":"Zongzheng Zhou,&nbsp;Yuhe Zhang,&nbsp;Shichun Jin,&nbsp;Lijun Xu,&nbsp;Lijie Hao,&nbsp;Siqin Meng,&nbsp;Hongliang Wang,&nbsp;Qiming Wang,&nbsp;Rui Luo,&nbsp;Baoji Zhu,&nbsp;Yuanqiao Li","doi":"10.1016/j.csite.2025.105940","DOIUrl":"10.1016/j.csite.2025.105940","url":null,"abstract":"<div><div>Metallic Magnetic Calorimeters (MMC) are low-temperature particle detectors based on calorimetry, typically operating at ultra-low temperatures below 100 mK, and they utilize metallic paramagnetic temperature sensors to convert the temperature rise of the absorber upon absorption of high-energy particles into changes in magnetic flux detected by a superconducting quantum interference device (SQUID). Therefore, the design of the MMC heat coupling system is directly related to the signal characteristics and performance of the MMC, making it particularly important for the design of MMC heat coupling systems. This paper, based on the basic principles of MMC signal conversion and the thermal coupling characteristics of components, combines actual conditions and uses the COMSOL heat conduction module to simulate the MMC heat coupling system. Key components of the MMC heat coupling system, including the absorber, thermal bottleneck, paramagnetic sensor, and weak thermal link, have been optimized in terms of parameter design. The optimized design is proposed based on simulation results and practical considerations. Simulation results show that for the detection of the characteristic 5.9 keV gamma rays from ⁵⁵Fe, when the MMC absorber thickness is reduced to 6 μm and the paramagnetic sensor thickness is reduced to 1.5 μm, the signal amplitude of the CMG-I can be increased by more than 100 % at a working temperature of 30 mK without affecting the MMC signal response and ensuring almost 100 % stopping power; by adding four gold posts between the absorber and the paramagnetic sensor as thermal bottlenecks, with a total cross-sectional area of 5.58 % of the absorber area, the process difficulty can be significantly reduced while ensuring complete thermalization of the incident energy within the absorber and essentially eliminating position dependence; the introduction of gold thermalization strip can provide a fully metallic thermal link from the absorber-paramagnetic sensor system to the rear thermal bath, reducing the relaxation time to approximately 4.844 ms, about one-third of the original design, which can significantly increase the count rate without significantly affecting the MMC signal amplitude and reduce the negative impact on energy resolution caused by signal pile-up. The research results have a significant guide for the design of MMC heat coupling systems.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105940"},"PeriodicalIF":6.4,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical thermal analysis of a real-case ladle in secondary steelmaking","authors":"M. Neri,&nbsp;H. Soltanian,&nbsp;A.M. Lezzi","doi":"10.1016/j.csite.2025.105899","DOIUrl":"10.1016/j.csite.2025.105899","url":null,"abstract":"<div><div>This paper proposes a 2D axis-symmetric numerical model designed in COMSOL Multiphysics to estimate power demand along the secondary steelmaking process. The analyzed process has been divided into cycles and phases included ladle preheating, waiting, filling, heating, continuous casting, and cleaning. Each cycle is modeled through 17 sequential time-dependent numerical simulations, and has been validated by comparing calculated temperatures with those measured in a steel plant. The study observes that the volumetric power demand decreases progressively over the cycles, stabilizing at 1.95 MW/m<span><math><msup><mrow></mrow><mrow><mn>3</mn></mrow></msup></math></span> after six cycles. Notably, the first cycle is by far the most power-consuming, accounting for nearly 20% of the total. Additionally, the ladle’s inner temperature drops by 300 °C within 30 min during the waiting phase between preheating and tapping, and by 400 °C within 55 min between two production cycles. The model is designed to qualitatively evaluate various factors associated with the secondary steel-making process, and it could be used within the framework of a DOE analysis for examining the impact of different variables to optimize energy management and other operations involving ladles.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105899"},"PeriodicalIF":6.4,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Squeezed silver-capped iron oxide nanoparticles flow and CCM heat transfer over a sensor surface: A synthesis and characterization","authors":"M.S. Sarvajith ,&nbsp;H.K. Prithviraj ,&nbsp;K. Ganesh Kumar","doi":"10.1016/j.csite.2025.105953","DOIUrl":"10.1016/j.csite.2025.105953","url":null,"abstract":"<div><div>The peculiar characteristics of silver-capped iron oxide nanoparticles (AgFe₃O₄) make them very valuable in a range of sensing applications. These nanoparticles are a combination of iron oxide's (Fe₃O₄) magnetic characteristics and silver's (Ag) antibacterial, catalytic, and electrical ones. This study aims to investigate how silver-capped iron oxide nanoparticles affect heat transfer in the Cattaneo-Christov model (CCM) for sensor surfaces. Additionally, we conducted the synthesis and characterization of silver-capped iron oxide nanoparticles for the application study. Using similarity transformations, we may get the leading equations' self-similar structure. For each given velocity of a sensor surface carrying silver-capped iron oxide nanoparticles, we have found similar solutions to the problem. The numerical solutions to the self-similar nonlinear equations are shown in graphs and tables. These show how the temperature and velocity gradient change for different parameter values. The main conclusions that can be identified in the work include the assertion that the velocity profile becomes flatter as the squeeze flow index (<span><math><mrow><mi>b</mi></mrow></math></span>) parameter value rises. Furthermore, As the <span><math><mrow><msub><mi>f</mi><mn>0</mn></msub></mrow></math></span> parameter is improved, the temperature of the fluid becomes more intense. The above-mentioned conclusions are highly relevant for the environment and biological applications of the results, primarily for those with an increased focus on the optimization of tracking the environment efficiency.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105953"},"PeriodicalIF":6.4,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization design of combustion chamber for a non-road diesel engine in high-altitude region","authors":"Yibing Hou ,&nbsp;Jun Wang ,&nbsp;Jilin Lei ,&nbsp;Liang Chen","doi":"10.1016/j.csite.2025.105943","DOIUrl":"10.1016/j.csite.2025.105943","url":null,"abstract":"<div><div>Modifying and optimizing the combustion chamber structure of diesel engines is one of the effective measures to improve in-cylinder combustion and reduce emissions in high-altitude areas. This study focuses on a non-road diesel engine running in a high-altitude environment of 2000 m. Initially, sensitivity analysis was conducted to identify the critical structural parameters of the combustion chamber at peak torque condition. Subsequently, a Latin hypercube sampling (LHS) approach was employed for experimental design, and a back-propagation (BP) neural network was utilized to develop a surrogate model. Finally, the non-dominated sorting genetic algorithm II (NSGA-II) was employed to perform multi-objective optimization, and the technique for order preference by similarity to ideal solution (TOPSIS) was utilized to select the optimal combustion chamber structural parameters suitable for high-altitude regions. Results show that the optimized combustion chamber improved in-cylinder fuel-air mixing and reduced emissions at high altitude. Compared to the original design, the optimized throat diameter (<em>D</em>_<em>i</em>) decreased by 6.22 %, height of the central protrusion (<em>T</em>_<em>m</em>) decreased by 1.57 %, and pit radius (<em>R</em>₄) increased by 3.87 %. The optimized brake specific fuel consumption (BSFC) remained almost unchanged at this altitude, while nitrogen oxides (NOx) and soot emissions were reduced by 12.47 % and 3.23 %, respectively.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"68 ","pages":"Article 105943"},"PeriodicalIF":6.4,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}