Nuclear Engineering and Design最新文献

{"title":"Effect of sintering temperature on crystal growth and evolution of CaZrTi2O7–CaNdTiNbO7 ceramics: Minor actinides immobilization host materials","authors":"Shiyin Ji ,&nbsp;Xiuhua Ji ,&nbsp;Yanhao Song ,&nbsp;Yanxia Wei ,&nbsp;Tao Duan","doi":"10.1016/j.nucengdes.2024.113643","DOIUrl":"10.1016/j.nucengdes.2024.113643","url":null,"abstract":"<div><div>Regulation of microstructure and processing cost of waste form are important for the design and application of high-level radioactive waste immobilization. In this study, CaZrTi₂O₇ (zirconolite) – CaNdTiNbO₇ (pyrochlore) ceramics were synthesized via conventional sintering method at 1000–1500 °C to investigate the effect of sintering temperature on the microstructure, solidification, and crystal evolution. The powder x-ray diffraction (XRD) and backscattered scanning electron microscopy–energy dispersive spectroscopy (BSEM–EDS) results indicated gradual formation of zirconolite and pyrochlore ceramics, following with their densification when increasing sintering temperature. It was found that sintering temperature should be higher than 1300 °C to form zirconolite-pyrochlore solid solutions. Densified pyrochlore was obtained at 1500 °C. In addition, transformation from relatively low-symmetry lattice to higher-symmetry lattice was found with an increase in sintering temperature. Furthermore, higher temperature can enhance the crystal growth and densification in the ceramic composite. The finding in this study could provide important suggestions to design and process zirconolite-pyrochlore waste forms for industrial application.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434309","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":"Dynamic response of hyperbolic cooling tower considering different column supporting systems subjected to seismic actions","authors":"Adil Ziraoui ,&nbsp;Benaissa Kissi ,&nbsp;Hassan Aaya ,&nbsp;Imane Ahnouz","doi":"10.1016/j.nucengdes.2024.113632","DOIUrl":"10.1016/j.nucengdes.2024.113632","url":null,"abstract":"<div><div>The seismic behavior analysis of a reinforced concrete cooling tower using SAP2000 aims to simulate and evaluate the structure’s response to seismic loads, both from near and far movements. This process begins with the creation of a numerical model that incorporates the tower’s geometry, construction materials, and anticipated seismic loads and constraints. The cooling tower is supported by I-type and Ʌ-type columns. Relevant comparisons of the dynamic response of the structural system have been made at the base level (where the columns meet the shell), throat level, and at the top of the tower. The results from these analyses enhance our understanding of the cooling tower’s seismic behavior, highlighting areas of excessive stress, potential deformations, and components vulnerable to damage during an earthquake. This information is vital for informing structural improvements that enhance the seismic resistance of the cooling tower and ensure its stability during seismic events, regardless of their proximity.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434311","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":"Mechanical behaviors and internal pressure bearing capacity of nuclear containment using UHPC and ECC: From numerical simulation, machine learning prediction to fragility analysis","authors":"Di Yao ,&nbsp;Ge Gao ,&nbsp;Qingyu Yang ,&nbsp;Feng Fan ,&nbsp;Jiachuan Yan","doi":"10.1016/j.nucengdes.2024.113617","DOIUrl":"10.1016/j.nucengdes.2024.113617","url":null,"abstract":"<div><div>This paper examines the use of Ultra-High Performance Concrete (UHPC) and Engineered Cementitious Composites (ECC) for containment structures subjected to internal pressure. It presents finite element models for these structures using UHPC, ECC, and conventional C60 concrete, validated through existing experimental data. The research compares the failure modes and mechanical behaviors of structures built from these materials. Findings show that UHPC and ECC have similar capacities for bearing internal pressure and demonstrate reduced deformation. Both materials notably diminish deformation, curtail cracking, and boost bearing capacity by approximately 30.6% compared to C60. To further analyze these properties, thirty parameter sets for C60 were created using the Latin hypercube sampling method and incorporated into the validated models to evaluate internal pressure capacity. Additionally, the study employed three machine learning algorithms (Bayesian networks, decision trees, and random forests) to predict bearing capacities effectively. With an additional thirty parameter sets, the random forest method emerged as the most precise. Parameter sets for UHPC and ECC were similarly generated and used to develop prediction models for the internal pressure capacities. In a broader scope, one hundred parameter sets across all three materials were analyzed using the random forest method. The maximum likelihood method assessed the fragility of these containment structures, providing statistical forecasts of the capacities to withstand internal pressures. This comprehensive analysis supports the application of UHPC and ECC in practical engineering contexts for containment structures.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434313","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":"Study on a leakage rate predictive model with Application in Multi-Conditions conversion for Double-Offset butterfly valves","authors":"Jiangfan Xiong ,&nbsp;Yubing Bu ,&nbsp;Guojun Zhang ,&nbsp;Jian Liu ,&nbsp;Guoliang Xu ,&nbsp;Xiaoming Huang","doi":"10.1016/j.nucengdes.2024.113630","DOIUrl":"10.1016/j.nucengdes.2024.113630","url":null,"abstract":"<div><div>A significant number of valves constitute a vital component of the containment pressure boundary of a nuclear power plant, and their leakage rates under accident conditions must be tightly controlled. In this study, a methodology for the construction of a predictive model of valve leakage rate is put forth the study of valve leakage characteristics under accident conditions. Taking the double-offset butterfly valves (DOBV) as the research object, its multi-parameter leakage rate predictive model is developed through finite element analysis (FEA) of the microscopic and macroscopic contact mechanics of the sealing, that are then combined with an existing interfacial leakage model. This model is able to predict the effects of different parameters, including the temperature, pressure, and humidity. It is then verified by comparing it with the experimental values of the multi-operating conditions leakage test. Based on this model, the impact of operating condition parameters on the leakage rate of the valve is numerically studied and a dimensionless leakage rate relationship is proposed: <span><math><mrow><msub><mi>Q</mi><mtext>r</mtext></msub><mo>=</mo><msub><mi>E</mi><mtext>P</mtext></msub><msub><mi>E</mi><mtext>T</mtext></msub><msub><mi>E</mi><mtext>m</mtext></msub></mrow></math></span>, where <span><math><msub><mi>E</mi><mtext>P</mtext></msub></math></span>,<span><math><msub><mi>E</mi><mtext>T</mtext></msub></math></span>,and <span><math><msub><mi>E</mi><mtext>m</mtext></msub></math></span> are pressure, temperature, and humidity conversion factors, respectively. These factors are in a power function relationship with their respective dimensionless state parameters. Further analysis demonstrates that the powers of these relationships are independent of roughness and weakly correlated with seal material and seal structure. The leakage pattern of this valve under two hypothetical accident scenarios is comparatively analyzed by applying the conversion equation, and some useful conclusions related to dynamic leakage rate control are drawn. The methodology presented in this paper is central to the contact seal leakage mechanism and can be extended to other containment penetrations.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428812","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":"Enhancing mechanical properties and radiation shielding of high-strength concrete with bulk lead oxide and granodiorite","authors":"Islam N. Fathy ,&nbsp;Alaa A. El-Sayed ,&nbsp;Maged E. Elfakharany ,&nbsp;Alaa A. Mahmoud ,&nbsp;Mohamed A. Abouelnour ,&nbsp;Abdelhalim S. Mahmoud ,&nbsp;Islam M. Nabil","doi":"10.1016/j.nucengdes.2024.113626","DOIUrl":"10.1016/j.nucengdes.2024.113626","url":null,"abstract":"<div><div>This paper evaluates the influence of bulk lead oxide (PbO) and granodiorite (GD) powders, individually and in combination at optimal replacement ratios, on the setting time, workability, compressive strength, and radiation attenuation properties of high-strength concrete (HSC). Twelve HSC mixes were prepared: a control mix, five mixes containing varying percentages of PbO, five mixes containing varying percentages of GD, and one hybrid mix combining 5 % PbO and 7 % GD. The optimal replacement ratio 7 % with GD powder increased the compressive strength of the concrete by 19.1 %. A comprehensive microstructural and compositional analysis of XBL/G-concrete was conducted employing X-ray Fluorescence (XRF), X-ray Diffraction analysis (XRD), Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray (EDX) techniques. Radiation shielding effectiveness was evaluated using Phy-X software and Monte Carlo-5 simulations (MCS), focusing on γ-rays and fast neutrons. 2 % replacement of PbO enhanced the compressive strength of the concrete. However, increasing the PbO content to 5 % resulted in an 8.57 % reduction in strength compared to the control mix. The hybrid concrete mix of 5 % PbO and 7 % GD demonstrated superior radiation shielding capabilities in terms of linear/mass attenuation, with a 3.12 % increase in compressive strength relative to the control sample. The combined concrete sample of 5 % PbO and 7 % GD were higher than the samples mixed with GD and lower than the samples mixed with PbO of concentrations 3, 4, and 5 % in terms of the linear/mass attenuation. The linear attenuation’s order of the XBL/G-concrete samples was: 1BG &lt; 3BG &lt; 5BG &lt; 7BG &lt; 9BG &lt; 1BL &lt; 2BL &lt; 5BLG7 &lt; 3BL &lt; 4BL &lt; 5BL. Also, the mixed concretes of 5 % PbO and 7 % GD demonstrated a superior from fast neutron shielding capabilities. The tested XBL/G-concrete samples provide adequate protection against γ-rays and fast neutrons for nuclear and medical facilities shield radiation.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428800","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":"Searching for optimal reactivity management using a new burnable absorber for SCLWR with (Th, 233U)O2","authors":"Nassar Alnassar ,&nbsp;Sitah Alanazi ,&nbsp;Muneerah A. Al-Aqeel ,&nbsp;Maha Algarawi ,&nbsp;Ahmed Salah Khaliil ,&nbsp;A. Abdelghafar Galahom","doi":"10.1016/j.nucengdes.2024.113631","DOIUrl":"10.1016/j.nucengdes.2024.113631","url":null,"abstract":"<div><div>This work investigates the efficiency of some new burnable absorbers (BAs) suggested to provide possible improvements in the fuel management of a supercritical light water reactor (SCLWR) assembly fueled with (Th, ²³³U)O₂. Four BAs including gadolinium, Erbium, Iridium and Lutetium are suggested as integral burnable absorber (IBA) rods. A three-dimensional model of SCLWR has been modelled using MCNPX version 2.7. A complete neutronic analysis has been carried out for the suggested BAs and compared with the gadolinium vector which is the common BAs. The IBA rods were distributed through the SCWR fuel assembly in a way that provided a flat power distribution. Various concentrations of the suggested BAs have been investigated to obtain the optimum value that can suppress the excess reactivity at the beginning of the cycle and flatten the infinite multiplication factor. The burnup parameters including the fertile, fissile, BAs and most effective fission product concentration as a function of effective full power days (EFPDs) of the SCLWR have been examined for the suggested BAs. The reactivity temperature coefficients have been studied to ensure the viability of the suggested BAs. A further analysis is performed to study the axial, radial power distribution and local power peaking factor.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428810","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":"Pre-disposal management of spent ion-exchange resins by Fenton oxidation treatment and conditioning in an alkali-activated matrix","authors":"Francesco Galluccio ,&nbsp;Andrea Santi ,&nbsp;Eros Mossini ,&nbsp;Gabriele Magugliani ,&nbsp;Fabio Fattori ,&nbsp;Giacomo Diego Gatta ,&nbsp;Paolo Lotti ,&nbsp;Davide Cori ,&nbsp;Elena Macerata ,&nbsp;Gianmarco Bilancia ,&nbsp;Mario Mariani","doi":"10.1016/j.nucengdes.2024.113621","DOIUrl":"10.1016/j.nucengdes.2024.113621","url":null,"abstract":"<div><div>The routine use of ion-exchange resins throughout the lifecycle of a nuclear facility poses significant issues regarding their safe and sustainable disposal at the end of their useful life. Effective strategies are thus required to overcome the challenging nature of this organic waste, aimed at minimizing volumes of the final waste forms, processing costs, and environmental impact. This work focuses on the pre-disposal management of spent mixed bed resins through the integration of a Fenton oxidative treatment process, an attractive environmentally friendly approach, and the successive encapsulation of the residues in an alkali-activated matrix. The successful treatment of a 20 g mix of cationic and anionic resins has led to a preliminary upscale of the process by using a surrogate waste (up to 200 g) loaded with representative activation and fission products contaminants. Some important process parameters were monitored, and the resulting residues were characterized. Finally, the obtained residues were encapsulated in an alkali-activated matrix with a loading factor up to 40 wt.%. Waste forms with residue loading factors up to 10 wt.% (corresponding to the conditioning of 0.6 kg of spent resin per kg of matrix) achieved preliminary compliance with waste acceptance criteria.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"High-Throughput falling ball viscometer for measuring High-Temperature molten salts","authors":"Alexander Levy ,&nbsp;Yifan Zhang ,&nbsp;Haoxuan Yan ,&nbsp;Anubhav Wadehra ,&nbsp;Yu Zhong ,&nbsp;Karl Ludwig ,&nbsp;Uday Pal","doi":"10.1016/j.nucengdes.2024.113612","DOIUrl":"10.1016/j.nucengdes.2024.113612","url":null,"abstract":"<div><div>The demand for clean energy production and storage has increased interest in molten salt technologies, including Molten Salt Reactors (MSR). Understanding of how molten salts properties change with respect to temperature and structure is vital to establishing efficient, cost effective MSR systems. Research into these materials however has been limited due to the difficulty in accurately measuring properties of these reactive materials at elevated temperatures and controlled environment in a time efficient way. Much research has turned to molecular dynamic (MD) modeling to alleviate these issues. This research presents a custom fabricated falling ball viscometer system for measuring molten salt viscosity quickly. A model for correlating velocity to viscosity for <em>Re</em> &lt; 300 was also developed for use with this system. The viscometer is demonstrated on eutectic FLiNaK and NaF-ZrF4 (53–47 mol%) up to 150 K above the respective melting points. The results are compared to MD simulations to verify their effectiveness for predicting viscosity and previously reported measurements.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428799","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":"Gas permeability and gamma ray shielding properties of concrete for nuclear applications","authors":"Daria Jóźwiak-Niedźwiedzka ,&nbsp;Marta Choinska Colombel ,&nbsp;Aneta Brachaczek ,&nbsp;Mariusz Dąbrowski ,&nbsp;Jakub Ośko ,&nbsp;Michał Kuć","doi":"10.1016/j.nucengdes.2024.113616","DOIUrl":"10.1016/j.nucengdes.2024.113616","url":null,"abstract":"<div><div>Concrete used in nuclear applications faces significant durability challenges due to degradation from radiation, thermal stresses, and chemical reactions. These issues highlight the critical need for impermeable concrete shields to prevent radioactive leaks and protect against harmful radiation. This study examines how concrete composition affects gas permeability and gamma radiation shielding properties. Three coarse aggregates—amphibolite (reference), magnetite, and serpentine—and two cement types (ordinary and slag) were tested, with concrete densities ranging from 2309 to 3538 kg/m³. Gas permeability was measured using a Cembureau-type constant head permeameter, and gamma shielding was assessed through the linear attenuation coefficient (µ) and half-value layer (HVL) at ¹³⁷Cs decay energies. The results revealed significant variations in gas permeability and gamma ray shielding based on aggregate and cement type, with observable relationships between gas permeability, HVL, and concrete density. The results obtained from the presented research will contribute to increasing the safety, durability and cost-effectiveness of concrete constructions and maintenance of nuclear facilities.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Mechanism model for effect of eccentricity on capacitive control rod position indicators","authors":"Yanlin Li,&nbsp;Benke Qin,&nbsp;Zijia Chen,&nbsp;Wei Xiong,&nbsp;Hanliang Bo","doi":"10.1016/j.nucengdes.2024.113628","DOIUrl":"10.1016/j.nucengdes.2024.113628","url":null,"abstract":"<div><div>The continuous identification technology for position signals based on the capacitive method has a good application potential in the field of the control rods position measurement in nuclear reactors. The main source for error of the Capacitive Control Rod Position Indicators (CCRPIs) comes from the effect of eccentricity. The conformal mapping technique was used in this paper, and the geometry of the CCRPIs could be transformed. A model for revealing the mechanism of the effect of eccentricity was established, and it was tested and verified by the method of numerical calculation. The characteristics of the distribution of the sensitive field was clarified by the model. The results indicate that the maximum error of the model is smaller than 13 %, and the eccentric effect of the indicator can be described by the model.</div></div>","PeriodicalId":19170,"journal":{"name":"Nuclear Engineering and Design","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428809","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}