Thermal Science and Engineering Progress最新文献

{"title":"Fluid flow and heat transfer in two-segmented microchannels within the slip flow regime","authors":"Younes Azizi ,&nbsp;Moslem Fattahi ,&nbsp;Arman Sadeghi","doi":"10.1016/j.tsep.2025.103751","DOIUrl":"10.1016/j.tsep.2025.103751","url":null,"abstract":"<div><div>We theoretically investigate gaseous slip flow and heat transfer in circular microchannels with two different wall materials in the lateral direction. The flow is considered as steady and fully-developed, and constant but different wall heat fluxes are assumed for the channel segments. While infinite series solutions are obtained for the velocity and temperature distributions as well as the Nusselt number, finite-element numerical simulations are also performed to confirm the validity of the analytical solutions developed. It is demonstrated that the average Nusselt number of the channel depends on several parameters comprising the Knudsen number, the Prandtl number and specific heat ratio of the gas, the momentum and thermal accommodation coefficients, and the angular span of either channel segment as well as the heat flux ratio of the two segments. It is further illustrated that the fluid velocity is strongly non-uniform in the angular direction when the channel segments have different momentum accommodation coefficients. This significantly affects the heat transfer rates, especially at high Knudsen numbers where the rarefaction effects are more significant. An inspection of the dimensionless average velocity variations shows that reducing the momentum accommodation coefficient of one channel segment while keeping that of the other one constant leads to higher average velocities, whereas the opposite is true for the influence of the thermal accommodation coefficient on the average Nusselt number. Finally, it is shown that the Nusselt number is a maximum for a symmetric wall heating.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103751"},"PeriodicalIF":5.1,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144231268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Moving boundary modeling during drying with intermittent microwave: The effect of pulse ratio","authors":"Jalal Dehghannya,&nbsp;Mahdi Habibi-Ghods","doi":"10.1016/j.tsep.2025.103745","DOIUrl":"10.1016/j.tsep.2025.103745","url":null,"abstract":"<div><div>Incorporating a moving boundary to represent shrinkage is vital in modeling transfer phenomena during drying. Lately, intermittent microwave drying has gained significant popularity due to its ability to produce superior dried food products. According to current literature, the simulation of pulsed microwave and its effect on coupled electromagnetic, moisture, and temperature distributions during combined drying with hot air using a moving boundary has not yet been investigated. This research examined various microwave pulse ratios (1 [continuous], 2, 4, and 6) with a fixed off-time of 180 s and a power of 900 W, alongside the control treatment (hot air; HA). The final moisture content decreased by 18.89 % with the increase in pulse ratio from 1 to 6, due to the accelerated moisture removal. Shrinkage and apparent density of the samples also decreased as the pulse ratio increased, due to enhanced porosity. The rehydration capacity at the pulse ratio of 6 was higher by 6.28 %. Energy consumption also decreased significantly by 31.32 % as the pulse ratio increased. Simulation results showed that the electric field was higher in the interior parts of the product due to the volumetric heating by microwave radiation compared to the edges. In the joint microwave and hot-air drying technique, due to the microwave’s volumetric heating mechanism, the internal temperature was higher than the surface temperature. Overall, the results showed that higher pulse ratios could produce dried products of better quality. The modeling procedure may be employed to optimize the combined microwave and hot-air drying process.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103745"},"PeriodicalIF":5.1,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144221781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a coupled transpiration cooling thermal protection system incorporating self-driven cooling pipes","authors":"Yumei Lv,&nbsp;Fei He,&nbsp;Xiaorong Wu,&nbsp;Peng Hu,&nbsp;Jianhua Wang","doi":"10.1016/j.tsep.2025.103744","DOIUrl":"10.1016/j.tsep.2025.103744","url":null,"abstract":"<div><div>To address the growing thermal loads of scramjet engines, a Coupled Transpiration Cooling Thermal Protection System (CTCTPS) integrated with self-driven cooling pipes is proposed. This system combines an S-shaped cooling pipe and a transpiration cooling structure to achieve self-driven and adaptive cooling. It harnesses the heat flux differences on the pipe wall to drive coolant flow inside the pipe for internal structure cooling, while the liquid water in the pipe evaporates or changes phase to provide coolant for transpiration cooling. In this research, different heat flux differences (0–500 W/m²) are used to explore their impacts on fluid flow, phase change, and heat transfer characteristics within the system. The study reveals that the system can remarkably enhance the overall cooling capacity. During the phase change stage, the cooling efficiency of the transpiration cooling structure surface is about 2.7 times that of the local circulation flow stage, and the heat transfer coefficient peaks at 88. By adjusting the heat flux difference, the system can optimize cooling time and coolant consumption. The system eliminates the need for external driving devices by leveraging natural convection induced by heat flux differences and effectively circumvents the instability issues caused by direct phase transitions in porous structures. This work paves a new pathway for comprehensive thermal management system of scramjet engine via the rational design of the CTCTPS with self-driven cooling pipes.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103744"},"PeriodicalIF":5.1,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144239947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance improvement of photovoltaic/thermal system using microencapsulated phase-change material suspension","authors":"Feng Shan ,&nbsp;Guiyin Fang ,&nbsp;Lei Zhao","doi":"10.1016/j.tsep.2025.103743","DOIUrl":"10.1016/j.tsep.2025.103743","url":null,"abstract":"<div><div>Featuring a radiative cooling (RC) film coated on the top cover glass and a microencapsulated phase-change material suspension (MEPCS) as the coolant, a novel photovoltaic/thermal (PV/T) system was proposed in this work for enhanced electrical performance and simultaneous thermal output. A rigorous numerical model was established for the PV/T system, the physical properties of MEPCS were systematically characterized, and the performance of a stand-alone PV panel and the PV/T system was compared numerically. The parametric analysis revealed that the inlet temperature of the coolant was the most critical operating parameter affecting the system performance. Specifically, under the meteorological conditions of July in Nanjing, the total electrical generation of the PV panel, water-based PV/T system, and MEPCS-based PV/T system were 18.18 kWh/m², 18.86 kWh/m², and 18.99 kWh/m², while the total thermal generation of the water- and MEPCS-based PV/T systems were 312.21 MJ/m² and 347.26 MJ/m², respectively. The MEPCS-based PV/T system was a more advantageous solution for solar applications, especially for the tropics with abundant solar resources.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103743"},"PeriodicalIF":5.1,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144204334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying thermal deformation upon ultraviolet nanosecond laser micro-drilling of copper foil","authors":"Yujie Han,&nbsp;He Li,&nbsp;Shuo Jin,&nbsp;Junjie Zhang","doi":"10.1016/j.tsep.2025.103723","DOIUrl":"10.1016/j.tsep.2025.103723","url":null,"abstract":"<div><div>While laser micro-drilling is promising for metal foil patterning, the inevitably thermal deformation of metal foil under laser ablation significantly deteriorates the patterning accuracy. In the present work, we investigate the characteristics, mechanisms and suppressing strategy of thermal deformation in ultraviolet nanosecond laser micro-drilling of copper foil with a thickness of 100 μm by means of analytical analysis, numerical simulations and experiments. Specifically, an on-site measurement method based on laser displacement sensors is proposed and developed, which is used to dynamically monitor the deformation degree of ablated area in the on-going laser ablation process, thus providing experimental evidence of thermal deformation characteristics of copper foil. Subsequently, a thermo-mechanical coupled finite element model considering the instantaneous material removal is developed, through which the underlying mechanisms governing the thermal deformation of copper foil are elucidated, and an analytical model correlating internal stress distribution with deformation behavior is derived accordingly. Finally, a novel strategy for suppressing laser ablation-induced thermal deformation of copper foil by applying pre-tension force is proposed, the effectiveness of which is theoretically and experimentally demonstrated. And a critical value of pre-tension force for achieving the maximum reduction of 93.1 % of thermal deformation of copper foil is discovered. This work provides a feasible method to quantify and eliminate thermal deformation of copper foil under laser ablation.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103723"},"PeriodicalIF":5.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improvement of intermittent microwave drying of red peppers: Effect of ethanol and blanching pretreatments on drying behavior, modeling, energy consumption and some quality attributes","authors":"Fadime Begüm Tepe,&nbsp;Tolga Kağan Tepe","doi":"10.1016/j.tsep.2025.103734","DOIUrl":"10.1016/j.tsep.2025.103734","url":null,"abstract":"<div><div>This research explores the potential of intermittent microwave drying as an alternative to sun and hot air drying. It also evaluates ethanol immersion (a new pretreatment method), along with traditional hot water and steam blanching pretreatments, to enhance drying efficiency. Key aspects studied include drying characteristics, moisture diffusion, thermal properties, energy consumption, modeling techniques, color changes, and shrinkage in red peppers. The drying was performed at 80, 240, and 400 W, with pretreated samples dried at 240 W. The shortest drying time was 27.5 min at 400 W and 40 min with 100 % ethanol at 240 W (240 W-100ET10) for pretreatments. The highest effective moisture diffusivities (D_eff) and mass transfer coefficients (h_m) for unpretreated samples were at 400 W. Among pretreatments, 240 W-100ET10 had the highest D_eff and h_m. Artificial neural network modeling outperformed thin layer modeling with higher R² and lower RMSE. Thermal properties, including specific heat and thermal conductivity, decreased during drying. The highest specific moisture evaporation rate and lowest specific energy consumption were 0.244 kg kWh⁻¹ and 4.105 kWh kg water^-1, respectively, for 240 W-100ET10. L* values decreased during drying, with notable changes in a* and b* values. Besides, thickness shrinkage decreased by higher microwave power and pretreatments. According to principal component analysis, hot and steam blanching and 400 W, %50 ethanol immersion for 10 min and 240 W, 80 W and 240 W-100ET10 showed similarities. Ethanol pretreatment and higher microwave power may be considered as promising methods for optimization of intermittent microwave drying of red peppers.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103734"},"PeriodicalIF":5.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of nonlinear heat transfer mechanisms in high geotemperature tunnels considering construction hydration heat effects","authors":"Xinrong Liu ,&nbsp;Liang Xu ,&nbsp;Xiaohan Zhou ,&nbsp;Yan Wang ,&nbsp;Yanhua Zeng ,&nbsp;Xin Chen","doi":"10.1016/j.tsep.2025.103737","DOIUrl":"10.1016/j.tsep.2025.103737","url":null,"abstract":"<div><div>To address the problem of temperature-induced cracks in high-temperature tunnel lining structures, which are susceptible to the coupling effects of support timing and hydration heat, this study establishes a transient numerical calculation model of the radial temperature field for tunnels under construction using the finite difference method. The primary focus is to analyze the influence of support parameters and environmental factors on the lining temperature field, with the goal of optimizing thermal management of tunnel linings to prevent temperature-induced structural issues. The main conclusions are as follows: (1) Hydration heat has a pronounced impact on the temperature distribution within tunnel linings, leading to a maximum temperature variance of 51.52 °C between the interior and exterior surfaces. (2) In standard lining structures, ambient temperature is linearly related to both the Maximum temperature difference within the secondary lining and the stabilized temperature at the outer surface. Return air velocity influences these temperature metrics through exponential relationships, characterized by upward and downward convex curves. Similarly, the time interval between the construction of initial support and secondary lining shows an exponential correlation with these temperature metrics, exhibiting downward convex curves. (3) For sandwich-type lining structures, the thickness of the insulation layer impacts the Maximum temperature difference and stabilized surface temperature through exponential relationships, resulting in upward and downward convex curve patterns, respectively.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103737"},"PeriodicalIF":5.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144230782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and characterization of a laboratory scale high flux solar simulator","authors":"Ravi Singh ,&nbsp;Pradip Dutta","doi":"10.1016/j.tsep.2025.103742","DOIUrl":"10.1016/j.tsep.2025.103742","url":null,"abstract":"<div><div>In this work, a combined experimental and numerical method is presented for the design and characterization of a high-flux solar simulator consisting of four lamp-reflector units. A direct characterization method is employed, using a heat flux sensor along with ray tracing-based numerical simulation of heat flux map to determine the arc volume geometry and optimum tilt angle for maximum transfer efficiency. The simulated heat flux map agrees reasonably well with the experimental measurements, in terms of peak flux as well as radial distribution. The 10 kW solar simulator achieves a maximum flux of about 1580 kW/<span><math><mrow><msup><mrow><mi>m</mi></mrow><mn>2</mn></msup></mrow></math></span> and an average flux of about 630 kW/<span><math><mrow><msup><mrow><mi>m</mi></mrow><mn>2</mn></msup></mrow></math></span> on a 70 mm diameter target with the transfer efficiency of 25.4 %. Varied flux levels are achieved by adjusting input power to the lamps and altering the target’s height. The present paper also describes the design and development of an environmental chamber, which serves the dual purpose of thermal management as well as housing for the simulator.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103742"},"PeriodicalIF":5.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144221783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance improvement of single slope solar distiller by using a novel corrugated–concave absorber: An experimental comparative study with energy, exergy, enviro–economic (4E), and sustainability assessments","authors":"Ridha Boudhiaf ,&nbsp;Khaled Harby ,&nbsp;Mohammed El Hadi Attia ,&nbsp;Mohamed Abdelgaied ,&nbsp;Majdi Amin ,&nbsp;Zied Driss","doi":"10.1016/j.tsep.2025.103730","DOIUrl":"10.1016/j.tsep.2025.103730","url":null,"abstract":"<div><div>This work aims to study the effect of absorber shape designs on the thermal performance of single-slope solar distillers to achieve the highest daily output and lowest production cost. Three single-slope solar distillers with different water absorber designs, flat (SSSD-FA), concave (SSSD-CA), and corrugated-concave (SSSD-CCA) were proposed, tested, and compared under the same conditions in the Sfax region, central–eastern of Tunisia. The proposed absorbers were made of the same materials and had the same dimensions. It is worth noting that the corrugated-concave absorber shape is an innovative design and has not been considered in any previous studies. The corrugated-concave absorber design features an inward concave surface with a series of grooves (waves), providing a large surface area for evaporation that is exposed to incident solar radiation compared to a flat design of the same projected area. Thus increasing the evaporation rate and daily productivity. The outcomes showed that the daily yield enhanced by 33.54 % and 60.89 %, respectively, for SSSD-CA (4.10 Lm⁻² day⁻¹) and SSSD-CCA (4.94 Lm⁻² day⁻¹) compared with that of SSSD-FA. The SSSD-CCA enhanced the daily energy efficiency by 57.81 % and 18.52 % as compared to SSSD-FA and SSSD-CA, respectively. The energy payback period for SSSD-FA, SSSD-CA, and SSSD-CCA are 1.47 years, 1.31 years, and 1.28 years, respectively. The exergy payback period for SSSD-FA, SSSD-CA, and SSSD-CCA are 33.72 years, 24.95 years, and 21.85 years, respectively. The reduction in yield cost by SSSD-CA ($0.050 L⁻¹) and SSSD-CCA ($0.042 L⁻¹) was about 26 % and 50 %, respectively, as compared to the SSSD-FA. This indicates the novelty and feasibility of using the proposed corrugated-concave basin design in increasing the performance of solar stills while reducing the cost of distillation.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103730"},"PeriodicalIF":5.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144212943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Configuration optimization of novel multi-grade waste heat streams coupling and utilization system for enhancing energy efficiency of coking plants","authors":"Fangtian Sun,&nbsp;Kai Liu,&nbsp;Zhicheng Wang","doi":"10.1016/j.tsep.2025.103741","DOIUrl":"10.1016/j.tsep.2025.103741","url":null,"abstract":"<div><div>Recovering waste heat plays a crucial role in enhancing energy efficiency of the coking plants, thereby contributing to the advancement of carbon peak and carbon neutrality. However, overall thermal performance of current coking waste heat recovery processes is relatively low. To solve the problem, three novel systems for coupling and utilizing multi-grade waste heat streams are proposed based on the progressive optimization principle, and they are designated as the ST-AHP-CCP, ST-AHP-CCHP, and ST-AHP-SE-CCHP. The ST-AHP-CCP is used to recover high- and medium-grade waste heat for generating power and producing chilled water at 16°C. To efficiently recover low-grade waste heat, the ST-AHP-CCP is integrated with a heating subsystem, forming the ST-AHP-CCHP. To improve the alignment between energy supply and demand, a hybrid ejector subsystem is integrated into the ST-AHP-CCHP, thus forming the ST-AHP-SE-CCHP. The three proposed systems are analyzed from the perspectives of thermodynamics and economics. The results indicate that overall performance of the ST-AHP-SE-CCHP is the highest among that of the three proposed systems. Thus, the energy conversion and utilization process of the ST-AHP-SE-CCHP is more advanced, and its system configuration is optimal. For the ST-AHP-SE-CCHP, annual utilization rate of waste heat, annual system production exergy efficiency, and payback period are approximately 44.4 %, 67.7 %, and 3.1 years, respectively. If the ST-AHP-SE-CCHP were applied to all coking plants in northern China, it would save approximately 8.67 × 10⁹ Nm³ of natural gas per year and reduce annual carbon emissions by about 1.80 × 10⁷ tons.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"63 ","pages":"Article 103741"},"PeriodicalIF":5.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144204333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}