Progress in Nuclear Energy最新文献

{"title":"Development of a new process for the radioactive ion exchange resins conditioning - HYPEX ®","authors":"Francesca Crivelli ,&nbsp;Silvio Cao ,&nbsp;Marino Corrado ,&nbsp;Claudio Mascialino ,&nbsp;Laura Savoldi ,&nbsp;Giancarlo Ventura","doi":"10.1016/j.pnucene.2025.105639","DOIUrl":"10.1016/j.pnucene.2025.105639","url":null,"abstract":"<div><div>A novel process, HYPEX®, for the conditioning of radioactive ion-exchange resins (IEXs), has been developed and is presented here. The process involves the immobilization of radioactive IEXs into a geopolymer matrix after grounding down to a micrometer scale and a complete hydration. The studied geopolymers are based on metakaolin and activated by an alkali solution. The effects of <em>∼</em> <span><math><mrow><mn>90</mn></mrow></math></span> different combinations of the structural atomic ratios in the geopolymer, such as silicon/aluminum (Si/Al) and water/aluminum (H₂O/Al), on macroscopic mechanical properties were examined, aiming at identifying the most suitable geopolymer for the conditioning of spent resins. Two geopolymer formulations were selected, both utilizing a fully sodium-based alkali solution and enriched with calcium hydroxide and siliceous inert filler to enhance their mechanical properties. One formulation involves the use of sodium silicate, while the other incorporates silica fume. Fractions of 20%wt and 30%wt of treated resin were added to the selected geopolymer matrices, and several tests were carried out in accordance with the Italian Safety Criteria for the Management of Radioactive Waste as far as resistance to compression, water immersion, thermal cycles, radiation, leachability, fire, and gas permeability are concerned. It is demonstrated here that HYPEX® satisfies the stringent Italian Criteria, even when 30%wt of resin is embedded.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105639"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143140996","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":"Research on fluctuation attenuation and optimization of passive residual heat removal system based on spring vibrator","authors":"Sipeng Wang ,&nbsp;Jin Chen ,&nbsp;Zehang Kang ,&nbsp;Peng Du ,&nbsp;Zhen Su ,&nbsp;Kun Zhuang","doi":"10.1016/j.pnucene.2024.105585","DOIUrl":"10.1016/j.pnucene.2024.105585","url":null,"abstract":"<div><div>The potential for flow and pressure fluctuation in passive residual heat removal systems (PRHRS) to result in equipment damage underscored the necessity for the development of effective mitigation strategies. In order to reduce the flow instabilities that occurs in the PRHRS, the idea of a fluctuation attenuation scheme based on a spring vibrator structure had been proposed. The structure was based on pressure pulsation attenuator in hydraulic systems and had been optimized. A model of a spring vibrator fluctuation attenuation pipe section was developed and its fluctuation attenuation effect was verified under specific parameters. Such as branch pipe length, cavity cross-sectional area, spring vibrator position, spring vibrator stiffness coefficient, and piston mass. The impact of these factors on fluctuation attenuation was investigated. The results demonstrated that, under identical inlet fluctuation conditions, the fluctuation peak at outlet of the pipe containing spring vibrator structure decreased. The optimization of the above parameters had been demonstrated to enhance the fluctuation removal effect of the spring vibrator structure. This study presented a novel approach to relieve flow instability in PRHRS.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105585"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141586","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":"Experimental research on the two-phase turbulent mixing between rod bundle subchannels with spacer grid","authors":"Zaiyong Ma ,&nbsp;Shasha Liu ,&nbsp;Luteng Zhang ,&nbsp;Wan Sun ,&nbsp;Changwen Liu ,&nbsp;Qi Lu ,&nbsp;Liangming Pan","doi":"10.1016/j.pnucene.2024.105582","DOIUrl":"10.1016/j.pnucene.2024.105582","url":null,"abstract":"<div><div>The turbulent mixing between rod bundle subchannels is a crucial phenomenon affecting the calculation accuracy of thermal-hydraulic parameters in reactor cores. Currently, studies on two-phase turbulent mixing mainly focused on the effects of flow regimes, rod bundle arrangement and gap spacing, etc., but seldom addressed the influence of spacer grid. In this paper, experiment of the two-phase turbulent mixing characteristics between rod bundle subchannels with spacer grid was conducted with tracer and visualization method. In the low void fraction region, the effects of spacer grid in enhancing phasic turbulent mixing was confirmed, but the enhancement would tend to disappear for large void fraction. It was also found that the effects of spacer grid on gas phase turbulent mixing were larger than that of liquid phase. Studies showed that with the increase of void fraction in the region of 0–0.65, the dimensionless liquid phase turbulent mixing rate was almost constant but decreased slightly for void fraction greater than 0.5, while the dimensionless gas phase turbulent mixing rate would increase. Existing models were also assessed with the experimental data, and it was found that Bues model could generally predict the total turbulent mixing of two-phase flow well if proper <em>θ</em>_max was provided, and Carlucci model could also predict the data of liquid phase turbulent mixing well, but may overestimate the data of gas phase turbulent mixing rate to a large extent.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105582"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141587","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":"An efficient AI algorithm for fault diagnosis in nuclear power plants based on machine deep learning techniques","authors":"Ayman A. Elbordany ,&nbsp;Magy M. Kandil ,&nbsp;Hassan A. Youness ,&nbsp;Hammam M. Abdelaal","doi":"10.1016/j.pnucene.2024.105580","DOIUrl":"10.1016/j.pnucene.2024.105580","url":null,"abstract":"<div><div>Artificial intelligence (AI) techniques and human intelligence are inextricably linked when it comes to operating Nuclear Power Plants (NPPs) with cutting-edge control rooms that have humans acting as actors. Using AI in fault diagnosis and prediction of accidents is valuable and crucial at NPPs. This research proposes an AI fault diagnosis algorithm for NPPs that uses AI techniques to integrate cutting-edge machine learning (ML) algorithms such as Support Vector Machine, Random Forest, k-Nearest Neighbors, Light Gradient Boosting Machine, and Long Short-Term Memory as deep learning (DL) algorithm to improve decision-making of operators to reduce the human errors in NPPs for increasing their safety. The proposed algorithm seeks to fault diagnosis by predicting and identifying normal and abnormal operations for Turbine trip with Anticipated Transient Without Scram (ATWS), Loss of Flow Accident (LOFA) and Loss of Coolant Accident (LOCA) with different break sizes (1,10,20,30,40,50,60,70,80,90,100 cm²) at hot leg. The dataset is pre-processed and enhanced to get complete and suitable inputs of the used ML and DL algorithms. The results show that the proposed AI fault diagnosis algorithm is effectively capable of anticipating and identifying risk according to predetermined cases since the accuracy is 98%. Moreover, validation of the proposed fault diagnosis algorithm with the previous model results also shows that the outputs are within range.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105580"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141591","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":"Rational approximations for multi-energy group stiff fractional point kinetics equations","authors":"Ahmed E. Aboanber ,&nbsp;Abdallah A. Nahla ,&nbsp;Omnia M. El-Sheikh ,&nbsp;Ashraf M. El-Mhlawy","doi":"10.1016/j.pnucene.2024.105570","DOIUrl":"10.1016/j.pnucene.2024.105570","url":null,"abstract":"<div><div>The statistical distribution of neutron density on nuclear reactors offers the benefit of having steady power for extended periods. However, changing the fuel and control rods could cause perturbations in this distribution. Therefore, it is necessary to investigate and analyze these perturbations to ensure the safe operation of reactors using a mathematically significant model of the Multi-Energy Group Point Kinetics Equations (MEG-PKEs). In this work, a multi-group of delayed neutrons (MGDN) and the stiff model of the multi-energy group fractional point kinetics equations (MEG-FPKEs) have been used to explore the behavior of neutron flux density. The stiff MEG-FPKEs have been solved with MGDN using various developed Padé approximations. Step, ramp, and sinusoidal reactivities, in addition to the nonlinear situation of reactivity in the presence of temperature feedback, are numerically examined using the fractional model. The developed mathematical model’s consistency, validity, and computational technique have been evaluated. Comparisons between the Padé approximations and the benchmark Heaviside’s expansion formula (HEF) prove complete agreement in the numerical results of 1EG-PKEs. In addition, Padé approximations reduce the computational CPU time compared to the benchmark HEF. Furthermore, the fractional order of the sub-diffusion and super-diffusion processes are investigated for different reactivity scenarios.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105570"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141632","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":"Mechanisms of crystalline swelling in bentonite buffer materials: Insights from molecular dynamics","authors":"Wen-jie Dai ,&nbsp;Yong-gui Chen ,&nbsp;Yu-cheng Li ,&nbsp;Wei-min Ye ,&nbsp;Qiong Wang ,&nbsp;Dong-bei Wu","doi":"10.1016/j.pnucene.2024.105586","DOIUrl":"10.1016/j.pnucene.2024.105586","url":null,"abstract":"<div><div>Compacted bentonite has been extensively studied due to its critical role in high-level radioactive waste (HLRW) disposal. Understanding the mechanism of crystalline swelling at the molecular level is essential for optimizing bentonite as a buffer material. To investigate the interplay between interlayer molecular conformation, migration, and interactions, molecular models of Na-montmorillonite (Na-Mt) were developed, and hydration behavior was examined through molecular dynamics (MD) simulations. The findings reveal that interlayer water molecules form distinct layers influenced by cation solvation and hydrogen bonding, with hydration layer conformations closely correlated to basal spacings. Na⁺ ions transition from inner-sphere to outer-sphere complexes due to hydration shell formation. The diffusion of Na⁺ ions is restricted by interlayer blocking and adsorption on clay surfaces. Under extreme drying conditions, strong attractions between Na⁺ ions and clay sheets result in interlayer collapse, with interlayer repulsion primarily driven by Coulomb electrostatic forces between adjacent clay sheets. Subsequently, the influx of water molecules acts as the driving force for crystalline swelling. Finally, the relationship between the hydration behavior of bentonite and montmorillonite was analyzed, providing valuable insights into the mineralogical mechanisms underlying Na-Mt swelling. These results contribute to a deeper understanding of bentonite's performance as a buffer material in HLRW repositories.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105586"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141633","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":"Acoustic characterization study for multi-hole orifices in nuclear piping system","authors":"Runlin Gan,&nbsp;Baoren Li,&nbsp;Jingrui Chu,&nbsp;Chang Yuan,&nbsp;Gang Yang","doi":"10.1016/j.pnucene.2024.105592","DOIUrl":"10.1016/j.pnucene.2024.105592","url":null,"abstract":"<div><div>The multi-hole orifices (MOs) present significant advantages, including the suppression of cavitation, enhanced flow stability, noise reduction, and displaying a wide range of potential applications in nuclear power piping systems. Currently, the research on MOs predominantly focuses on flow rate and pressure control, yet there is a notable gap in understanding the noise reduction mechanisms associated with the structural acoustic characteristics. It hampers the theoretical advancement of noise reduction design for MOs, and its ultimate practical engineering applications. A number of factors impact the acoustic properties of MOs, and different hole distributions and shapes result in different acoustic properties. This paper investigates various hole distributions and shapes within the background of meeting the low-noise performance requirements of MOs. The evaluation of acoustic performance is conducted based on flow velocity, cavitation, and transmission loss. The influence of hole distribution and shape on the acoustic performance of MOs is systematically analyzed. The results demonstrate that various hole distribution and shapes have diverse effects on the acoustic performance. The structural design with a circumference distribution of circular holes emerges as a critical fundamental type for realizing low-noise MOs. This paper offers valuable insights for the design of low-noise MOs.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105592"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141636","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":"Activity inventory of activated materials in distant components of the CENM TRIGA MARK II reactor for decommissioning planning","authors":"S. El Maliki El Hlaibi ,&nbsp;T. El Bardouni ,&nbsp;Y. Boulaich ,&nbsp;B. Nacir ,&nbsp;O. El Hajjaji ,&nbsp;M. Lahdour ,&nbsp;J. Al-Zain ,&nbsp;H. Ziani ,&nbsp;H. El Yaakoubi","doi":"10.1016/j.pnucene.2024.105569","DOIUrl":"10.1016/j.pnucene.2024.105569","url":null,"abstract":"<div><div>This paper presents a methodology for the activity inventory calculations of activated materials in the distant components of the Moroccan TRIGA MARK II reactor after its final shutdown. The induced activity calculations in components further from the core are more complex due to significant neutron flux attenuation away from the core and spatial variations in the neutron energy spectrum. The described method combines reaction rate calculations with the reactor operating history to estimate the neutron-induced activity in distant components. The MCNP6.2 code was used to calculate the neutron flux distributions throughout the reactor and activation reaction rates to estimate the activity inventory in distant components, including the most remote parts of the concrete shielding. Furthermore, the SSW/SSR technique was applied to support calculations in distant components, reducing the computing time and the statistics error. The activity inventory of activated materials in distant components is presented after a cooling period of six months following the final shutdown, and the main contributing radionuclides to the total activity for each material are identified.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105569"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141677","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":"Upgrading the compressive strength and radiation shielding properties of high strength concrete supported with nano additives of lead monoxide 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;K.A. Mahmoud ,&nbsp;Taha A. Hanafy ,&nbsp;M.I. Sayyed ,&nbsp;Islam M. Nabil","doi":"10.1016/j.pnucene.2024.105562","DOIUrl":"10.1016/j.pnucene.2024.105562","url":null,"abstract":"<div><div>The current study aims to enhance several properties of high-strength concrete (HSC) by incorporating two distinctly classified and inherently different nanomaterials into the concrete matrix ingredients. Nano-lead monoxide (NL), known for its high density and radiation attenuation capability, and nano granodiorite powder (NG), as a promising supplementary cementitious material (SCM) with pozzolanic activity ,were individually investigated at increasing replacement ratios of cement weight up to 5%. Additionally, an optimized mix containing the optimal replacement ratios of both materials was designed to maximize the concrete shielding capacity against radiation penetration. The NL/NG concrete was analyzed using XRF, XRD, SEM, and EDX techniques. The radiation shielding assessment of the examined NL/NG-concrete mixes were evaluated using the Monte-Carlo simulation and Phy-X software. Results showed the ability of NG to improve the compressive strength of HSC, where the optimum replacement ratio was 4%, with an increase of 17.3% compared to the control mix. This improvement was at lower rates in the case of NL, where a 3% replacement ratio resulted in a 7.96% increase in compressive strength before the strength value declined at higher replacement ratios. For the other properties, increasing the replacement ratio of NL in the concrete mix leads to a delay in setting times and an increase in workability, accompanied by a decrease in consistency. On the other side, the incorporation of NG into the concrete exhibited the opposite effect on all the properties above. The combined mix of 5%NL+4%NG led to an 11.7% enhancement in the compressive strength value with improved overall concrete performance, especially its radiation shielding property. The studied NL/NG-concrete samples provide the best protection against γ-rays. Lastly, the excellent performance of the mixes of NL and NG on HSC would pave the way for their employment as radiation shielding in various nuclear and medical facilities.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105562"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141679","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":"A new iterative method based on the Q-iteration method for robust and rapid determination of concentration distribution in multicomponent separation cascades","authors":"Ruinan Wu,&nbsp;Junlu Wu,&nbsp;Enchi Liu,&nbsp;Shi Zeng","doi":"10.1016/j.pnucene.2024.105561","DOIUrl":"10.1016/j.pnucene.2024.105561","url":null,"abstract":"<div><div>Determining the concentration distribution of mixtures of multiple isotopes in separation cascades is a common task in cascade analysis and design. The robustness and efficiency of the computational method are crucial, particularly for cascade optimization. The Q-iteration method is well known for its simplicity, robustness, and rapid convergence and applies to various cascades. However, extensive experience in computation with the Q-iteration method revealed three drawbacks in certain cases: difficulties in selecting a suitable relaxation factor and appropriate update direction, as well as insufficient convergence speed. This paper analyzes the convergence properties of the Q-iteration method and its associated drawbacks and, based on the Q-iteration method, proposes a novel iterative approach, termed Minimal Residuals Q-iteration method (MR Q-iteration method), utilizing the gradient information of <span><math><mi>Q</mi></math></span> to determine the update direction and step size at a low computational cost. Three typical cascade cases, each representing one of the drawbacks, are computed to compare the performances of both the Q-iteration method and the MR Q-iteration method. The results demonstrate that the new method effectively resolves the three drawbacks and has improved robustness and faster convergence compared to the Q-iteration method, while retaining its simplicity.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"180 ","pages":"Article 105561"},"PeriodicalIF":3.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141776","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}