Case Studies in Thermal Engineering最新文献

{"title":"Numerical thermodynamic-economic study and machine learning-based optimization of an innovative biogas-driven integrated power plant combined with sustainable liquid CO2 and liquid H2 production-storage processes","authors":"Ruijia Yuan, Fan Shi, Azher M. Abed, Mohamed Shaban, Sarminah Samad, Ahmad Almadhor, Barno Abdullaeva, Mouloud Aoudia, Salem Alkhalaf, Samah G. Babiker","doi":"10.1016/j.csite.2025.106043","DOIUrl":"https://doi.org/10.1016/j.csite.2025.106043","url":null,"abstract":"Innovative heat recovery, CO<ce:inf loc=\"post\">2</ce:inf> capture, and energy storage methodologies are pivotal for developing sustainable and eco-friendly solutions for the energy sector. Hence, this study proposes implementing an oxyfuel combustion process for a biogas power plant, modified by an innovative heat recovery method and a CO<ce:inf loc=\"post\">2</ce:inf> capture-liquefaction technique. Furthermore, the design incorporates high-temperature water electrolysis to produce hydrogen, which is then introduced into a hydrogen liquefaction process utilizing a Claude cycle for adequate long-term storage. The research employs thermodynamic, exergoeconomic, and net present value assessments, accompanied by an extensive parametric study and optimization process. Hence, a machine learning algorithm is implemented using artificial neural networks combined with the NSGA-II method for multi-criteria optimization, focusing on exergy efficiency, net present value, and products' sum unit cost as objective functions. The implemented optimization reduces the optimization time to under 30 min, which is significantly more efficient than traditional heuristic techniques, which typically require several hours for similar systems. This optimization framework is highly applicable to both industrial and district energy systems. This approach enhances predictive analytics and streamlines resource management. In industrial environments, it effectively optimizes energy use and production processes by examining various operational factors, which leads to cost reductions and improved efficiency via predictive maintenance and cohesive energy strategies. The optimal outcomes reveal the mentioned objective functions' values at 47.22 %, 58.73 M$, and 33.53 $/GJ, respectively. Under these optimal conditions, liquid carbon dioxide and liquid hydrogen outputs are quantified at 4931 lit/h and 1848 lit/h, respectively. Finally, the proposed system can omit CO<ce:inf loc=\"post\">2</ce:inf> emissions by 1.36 kg/kWh under optimal conditions, which reflects a 5.60 % better performance than the base case. Furthermore, the products’ sum unit cost decreases by 3.09 %, indicating efficient cost savings linked to the products.","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"67 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724020","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 on thermo-structural performance of honeycomb absorbers for concentrated solar power systems","authors":"Masoud Behzad ,&nbsp;Sébastien Poncet ,&nbsp;Cristóbal Sarmiento-Laurel","doi":"10.1016/j.csite.2025.106068","DOIUrl":"10.1016/j.csite.2025.106068","url":null,"abstract":"<div><div>Honeycomb volumetric solar receivers have emerged as promising candidates for concentrating solar power applications because of their thermal and mechanical properties, enabling the efficient heating of fluids. Despite their potential, challenges remain in optimizing channel design and operating conditions to enhance thermodynamic performance. This study identifies design and operating configurations that maximize the thermodynamic performance and structural reliability of silicon carbide honeycomb volumetric solar receivers, focusing on thermal efficiency and factor of safety. We adopted a multi-objective optimization approach by integrating computational fluid dynamics, heat transfer, and thermal stress analysis. To streamline computational efforts, the Taguchi method was employed, reducing the number of required simulations while maintaining a relative error below 5 %. A critical mass flow to absorbed power ratio of 5 × 10⁻⁶ (kg/s)/W was identified, beyond which thermal efficiency stabilizes, providing practical guidance for operational optimization. The optimal configuration achieved a thermal efficiency of 89.3 % and a factor of safety of 87.3 %, with a channel width of 3 mm, a thickness of 0.3 mm, an outlet static pressure of −70 Pa, and a radiation flux of 650 kW/m². These findings establish a robust framework for optimizing honeycomb receivers, addressing thermal and structural performance while maintaining simplicity in manufacturing processes.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"70 ","pages":"Article 106068"},"PeriodicalIF":6.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746817","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":"Artificial neural network-based online stroke detection for CO2 linear refrigeration compressors","authors":"Fanchen Kong ,&nbsp;Mingxuan Huang ,&nbsp;Shuo Zhang ,&nbsp;Zhouhang Hu ,&nbsp;Shanquan Liu ,&nbsp;Guifang Wu ,&nbsp;Mingsheng Tang ,&nbsp;Huiming Zou ,&nbsp;Changqing Tian","doi":"10.1016/j.csite.2025.106060","DOIUrl":"10.1016/j.csite.2025.106060","url":null,"abstract":"<div><div>CO₂ linear compressors are critical for sustainable and energy-efficient refrigeration systems due to the eco-friendly properties of CO₂. However, the unique characteristics of CO₂ compressors introduce significant challenges in piston stroke control. The large pressure difference between suction and discharge conditions requires high operating currents to overcome gas forces, resulting in substantial piston offsets. These offsets interact with nonlinear parameter variations, elevating the risk of resonant frequency shifts and potential valve collisions. Accurate piston stroke measurement is essential to address these issues, but traditional methods relying on displacement sensors are costly. This study presents an innovative artificial neural network (ANN) method for sensorless piston stroke measurement in CO₂ linear compressors. The proposed model requires only six inputs: voltage, current, frequency, active power, suction pressure, and discharge pressure. Optimized ANN parameters enable high prediction accuracy, with an average R² of 0.955, RMSE of 0.206, and an average error of 2.24 % on the testing set. Furthermore, a simple stroke adjustment method based on the ANN model is proposed, allowing for effective stroke control and natural frequency calculation.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"70 ","pages":"Article 106060"},"PeriodicalIF":6.4,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746816","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":"Chemical kinetic models, reaction mechanism estimation, and thermodynamic parameters for the non-isothermal decomposition of trona ore","authors":"Ceren Eda Delikurt,&nbsp;Meltem Kizilca Coruh","doi":"10.1016/j.csite.2025.106042","DOIUrl":"10.1016/j.csite.2025.106042","url":null,"abstract":"<div><div>Trona ore, a naturally occurring sodium carbonate mineral, is a crucial raw material in various industrial applications, particularly soda ash production. Despite its significance, trona's thermal decomposition kinetics and underlying reaction mechanisms remain underexplored, limiting the optimization of industrial-scale processing methods. This study comprehensively investigates the non-isothermal thermal decomposition of trona using thermogravimetric analysis under different heating rates in an N₂ atmosphere. To determine the activation energy (Ea) and reaction mechanisms governing the decomposition process, FWO, KAS, Tang, Starink, and CR methods were applied. The results indicate that the thermal decomposition follows a nucleation-controlled reaction mechanism <em>P</em>_<em>4</em> with activation energy values ranging from 122 to 131 kJ mol⁻¹, demonstrating that the process occurs through a single-step reaction. The thermodynamic analysis revealed that the decomposition process is endothermic, as indicated by the positive <em>ΔH</em> values, while the <em>ΔS</em> values suggest an increase in molecular randomness during decomposition. Additionally, <em>ΔG</em> calculations indicate that the reaction is non-spontaneous, necessitating external energy input. These findings provide critical insights into trona's kinetic and thermodynamic behavior, bridging the knowledge gap between experimental analysis and industrial processing applications. Unlike previous studies, this research comprehensively evaluates trona's decomposition behavior, offering valuable data for reactor design and process optimization.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"69 ","pages":"Article 106042"},"PeriodicalIF":6.4,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696638","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":"Comparative evaluation and economic analysis of metal- and carbon-based nanoadditives in low-viscous waste-derived biofuel blends for diesel engines","authors":"Xu Han, Ting Li, Guangchun Liu, Suresh Vellaiyan","doi":"10.1016/j.csite.2025.106057","DOIUrl":"https://doi.org/10.1016/j.csite.2025.106057","url":null,"abstract":"This study presents a comparative evaluation of two distinct nanoadditives: a metal-based additive (copper oxide, CuO) and a carbon-based additive (carbon nanotubes, CNTs), focusing on their effects on engine performance and emissions when blended with a biofuel derived from pomelo peel waste (PWB) and conventional diesel fuel (CDF). The PWB bio-oil was extracted via thermal distillation, and a 30 % PWB + CDF blend (CDF30PWB) was further modified with 100 ppm of CuO and CNT nanoparticles. Characterization of CuO and CNT confirmed their catalytic potential for fuel enhancement. Results indicate that CDF30PWB improved brake thermal efficiency (BTE) by 6.09 % compared to CDF, while CNT and CuO further increased BTE by 1.63 % and 3.12 %, respectively. Brake-specific fuel consumption (BSFC) was reduced by 3.95 % for CDF30PWB, with CNT achieving an additional 3.69 % reduction and CuO lowering BSFC by 2.1 %. Emissions analysis showed that hydrocarbon (HC) and carbon monoxide (CO) emissions were reduced by 8.13 % and 2.61 %, respectively, for CDF30PWB, while CNT-enhanced fuel achieved further reductions of 14.59 % (HC) and 14.93 % (CO), and CuO reduced them by 4.29 % and 8.5 %, respectively. NOx emissions increased by 5.15 % with CDF30PWB, but CuO incorporation led to a 12.56 % reduction, and CNTs reduced NOx by 8.45 %. Smoke opacity was lowered by 9.88 % with CuO and 11.05 % with CNTs. Economic analysis highlighted that CuO achieved a 19 % potential cost reduction. This study concludes that CuO is more effective in NOx mitigation at a lower cost, while CNTs optimize engine performance and reduce HC and CO emissions.","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"33 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724019","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":"Decoupling prediction of cooling load and optimizing control for dedicated outdoor air systems by using a hybrid artificial neural network method","authors":"Yongbo Cui ,&nbsp;Chengliang Fan ,&nbsp;Wenhao Zhang ,&nbsp;Xiaoqing Zhou","doi":"10.1016/j.csite.2025.106046","DOIUrl":"10.1016/j.csite.2025.106046","url":null,"abstract":"<div><div>Dedicated outdoor air systems (DOAS) can utilize high cooling water temperatures to achieve independent temperature and humidity control, which improves the energy efficiency of the system. Although many studies have investigated the energy consumption of DOAS under conventional controls, there is a lack of a cooling load (sensible load and latent load) decoupling control method to optimize DOAS operation. To address this challenge, this study introduces an Attention-Convolutional neural network-Long short-term memory (ACL) model, a hybrid deep learning framework explicitly designed for DOAS cooling load prediction. Unlike traditional approaches, the proposed ACL model decouples sensible and latent cooling loads, enabling precise load forecasting. First, a convolutional neural network (CNN) extracts critical cooling load features from building datasets. Finally, the ACL model-based control strategy is implemented through a co-simulation framework to optimize DOAS operating parameters. The results show demonstrate that the ACL model achieves an average prediction error of 5.7 %, with mean absolute proportional errors of 2.8 % for sensible cooling load and 1.9 % for latent cooling load. Moreover, the optimized ACL control strategy reduces DOAS power consumption by 7.7 %, ensuring energy-efficient operation in high-temperature, high-humidity environments. This study provides a new cooling load decoupling prediction control approach for DOAS, offering substantial energy savings.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"69 ","pages":"Article 106046"},"PeriodicalIF":6.4,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696097","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":"Effect of valve regulation on the operating state of a CO2 two-phase thermosyphon loop","authors":"Zhen Tong,&nbsp;Wencheng Wang,&nbsp;Peng Wang,&nbsp;Zekun Han,&nbsp;Huili Yu,&nbsp;Songtao Hu","doi":"10.1016/j.csite.2025.106055","DOIUrl":"10.1016/j.csite.2025.106055","url":null,"abstract":"<div><div>During the operation of two-phase thermosyphon loops (TPTLs), different types of oscillations may occur, affecting their safety and performance. Although existing research has preliminarily explored the use of valve regulation to eliminate oscillatory operations in TPTLs, the effects of valves on different types of oscillations have not been verified. In this study, valve regulation was applied to two types of oscillation in a CO₂ TPTL. The distinct effects of the valve on each type of oscillation were analyzed in conjunction with their respective mechanisms through experiment. For natural circulation oscillations, valve regulation can effectively suppress fluctuations within the loop. When the valve opening (<em>θ</em>) reduced from 100 % to 75 %, the TPTL transitioned from oscillatory to stable operation. However, the thermal performance of the TPTL remained nearly unaffected. For geyser boiling, valve regulation cannot alter the oscillatory operating state within the loop. Even when the <em>θ</em> was reduced from 100 % to 25 %, the TPTL remained in an oscillatory operating state. The results provide a deeper understanding of the influencing mechanisms of valve regulation and offer insights into the active regulation of TPTLs.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"69 ","pages":"Article 106055"},"PeriodicalIF":6.4,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704201","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 investigation of convective heat transfer to supercritical pressure n-decane and RP-3 under trans-critical and cracking states","authors":"Yinlong Liu, Jiaxin Chen, Guoqiang Xu, Nicolas Gascoin, Yanchen Fu","doi":"10.1016/j.csite.2025.106050","DOIUrl":"https://doi.org/10.1016/j.csite.2025.106050","url":null,"abstract":"The increasing demand for higher flight speeds in hypersonic vehicles has catalyzed the advancement of active regenerative cooling technologies based on endothermic hydrocarbon fuels. This work carried out experimental investigation on the convection heat transfer performance of supercritical n-decane and RP-3 within a horizontal GH3128 microtube with 2 mm inner diameter from room temperature to exceeding 50 % cracking conversion rate at 3−6 MPa. The rise rate of fuel temperature along the tube in the cracking reaction zone is lower than that in the inlet, trans-critical and supercritical zone. There exists heat transfer deterioration attribute to the inlet effect and inlet laminar flow in the inlet region, and the subsequent heat transfer enhancement induced by the significant buoyancy effect in the trans-critical region. Lower pressures lead to earlier onset and greater magnitudes of heat transfer enhancement. In the supercritical zone once the fuel temperature surpasses the quasi-critical temperature, no obvious heat transfer anomaly occurs. Upon the onset of the cracking reaction, a slight augment in the convection heat transfer coefficient is obtained, attributed to the increase in the thermal conductivity of the cracking mixture. This work provides valuable support for the thermodynamic design of hypersonic vehicle cooling channels.","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"36 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724022","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":"Investigation on variable properties in thermo-electroosmotic peristaltic flow","authors":"N. Naheed ,&nbsp;S. Noreen ,&nbsp;Muhammad Idrees Afridi","doi":"10.1016/j.csite.2025.106049","DOIUrl":"10.1016/j.csite.2025.106049","url":null,"abstract":"<div><div>Accurate modeling and optimization in many technical and biological applications depend on an awareness of the complex link between temperature-dependent viscosity and thermal conductivity. Focusing on how temperature fluctuations affect fluid characteristics and system performance, this work explores the electromechanical propulsion of non-Newtonian fluids in a symmetric sinusoidal channel. Under lubrication assumptions and Debye-Huckel linearizing, the mathematical model combines equations for continuity, Poisson, energy, momentum, concentration, and electric potential. Variations in temperature conditions clearly influence flow dynamics, heat transfer rates, pressure gradients, and general system efficiency according to analytical solutions to the ensuing nonlinear partial differential equations. Especially, increasing the Weissenberg number improves the heat transfer coefficient; greater Helmholtz-Smoluchowski velocities raise the pressure gradient profile. Furthermore, in the absence of Helmholtz–Smoluchowski effects, streamlines remain symmetric and smooth; nevertheless, their presence causes significant changes in streamline patterns. These results show the need of considering temperature-dependent fluid characteristics in practical applications as they offer insightful information for the design and optimization of electroosmotic systems and peristaltic pumps.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"70 ","pages":"Article 106049"},"PeriodicalIF":6.4,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746846","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":"A novel energy management strategy for LNG ambient air vaporizer coupled with water-bath heater system","authors":"Lemei Ren, Wenling Jiao, Guansan Tian","doi":"10.1016/j.csite.2025.106052","DOIUrl":"https://doi.org/10.1016/j.csite.2025.106052","url":null,"abstract":"Water-bath heater (WH) is typically installed in series behind ambient air vaporizers (AAVs) to heat liquefied natural gas (LNG) to a desired temperature, while accounting for the uncertainty in the heat transfer performance of AAV. This paper proposes a novel energy management strategy for an LNG AAV coupled with WH system to reduce the energy consumption of the WH. The strategy incorporates a heat transfer model for the AAV and a compensator model for the WH to determine the hot water supply temperature. By utilizing these models, the heat transfer capacity of the WH can be adjusted based on the variations in the AAV's heat transfer performance and the flow rate of the exported natural gas (NG). Operational data from LNG gasification stations were employed to validate these models. Additionally, an example was provided to compare the novel and traditional strategies. The energy consumption was reduced by 40 %, and the temperature fluctuations of the exported NG were maintained within a narrow range, not exceeding 1 °C. These findings indicate that the novel energy management strategy significantly improves the efficiency of LNG gasification and decreases energy consumption.","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"183 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724023","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}