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Performance evaluation and sensitivity analysis of GPU-accelerated QES against wind tunnel experiments for air dispersion modeling under heterogeneous terrain and dense building at an AP1000 NPP site

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Progress in Nuclear Energy 2025年 188卷

作者： Zhaoyang Wang Sheng Fang Li Yang Xinpeng Li Yixue Chen School of Nuclear Science and Engineering North China Electric Power University Beijing 102206 China Institute of Nuclear and New Energy Technology Collaborative Innovation Centre of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University Beijing 100084 China

Accurate air dispersion modeling can effectively support nuclear accident emergency decision-making and emergency planning zone (EPZ) optimization, for improved safety and economic efficiency of advanced nuclear power plants (NPPs). However, fast and detailed air dispersion modeling remains challenging for heterogeneous terrain and dense building environments. This study presents the GPU-accelerated Quick Environmental Simulation (QES) system for simulating high-resolution wind and concentration field in the presence of heterogeneous terrain and dense buildings, and validates it against two wind tunnel experiments of an AP1000 site, evaluating wind direction, speed, and pollutant concentration in both horizontal and vertical profiles. Sensitivity analyses were conducted on solver options, number of released particles per second, non-local mixing coefficients, and grid sizes. The findings demonstrate that GPU-QES successfully reproduces the vortices between buildings and takes only 4 s to simulate a detailed 3 km × 3 km wind field with 35 million grids. For wind fields, more than 50 % of the simulations were within a factor of two of the observations. For concentration fields, the fraction of simulations within a factor of two/five exceeds 51 % and 85 %, respectively, which are 21 % and 15 % higher than the acceptable lower limits, confirming QES's capability for small-scale modeling at this NPP site. Sensitivity analyses suggest the optimal parameters: global memory solver, released particles per second of 200, non-local mixing coefficients of 0.3 m 2 /s 2 , and grid size of 5 m both horizontally and vertically in similar scenarios. For the site boundary that is important in determining EPZ, the GPU-QES is only 49 % lower than the measurement, whereas the straight-line Gaussian plume model overestimates by 8.23 times, proving GPU-QES's potential in optimizing the EPZ.

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Runoff Generation Mechanism of Small Forest Watersheds in Humid Regions of China Under Single Rainstorm Conditions

SSRN

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SSRN 2024年

作者： Sheng, Fei Wang, Yanyan Nie, Xiaofei Liu, Shiyu Zheng, Haijin Chen, Guangjie Zhou, Changming Yi, Tingxin Liu, Zhao Jiangxi Academy of Water Science and Engineering Jiangxi Nanchang330029 China Jiangxi Key Laboratory of Watershed Soil and Water Conservation Jiangxi Nanchang330029 China Jiangxi Provincial Technology Innovation Center for Ecological Water Engineering in Poyang Lake Basin Jiangxi Nanchang330029 China Jiangxi Institute of Survey & Design LTD. Jiangxi Nanchang330038 China Jiangxi Agricultural University Jiangxi Nanchang330045 China Key Laboratory of Poyang Lake Watershed Agricultural Resources and Ecology Jiangxi Agricultural University Jiangxi Nanchang330045 China

Study region: Pengchongjian small watershed in southeastern *** focus: From 1983 to 2017, precipitation and runoff characteristics during single rainstorm conditions within the watershed were analysed. Alterations in the runoff generation mechanism were investigated in conjunction with the underlying surface *** hydrological insights for the region: The findings revealed that in comparison to the baseline period (1983–2003), there was a 4.6% reduction in average precipitation and a 23.8% decrease in average runoff depth during the changing period (2004–2017). The correlation between runoff depth and precipitation decreased during the changing period. There was an extremely significant upward trend in the normalised difference vegetation index, and the forest coverage increased from 80% to 98%. The soil fertility and water conservation capacity of the main stands of Chinese fir forests were enhanced. Under the conditions of a single rainstorm, the predominant runoff generation pattern observed during various periods was saturation-excess runoff. During the baseline period, the proportion of saturation-excess runoff was 45.3%, which increased to 52.9% in the changing period. In contrast, the infiltration-excess runoff decreased from 36.8% to 32.9%. Additionally, the mixed runoff decreased from 17.9% to 14.2%. Meanwhile, the probability of interflow and subsurface runoff generation increased. The findings provide a scientific basis for mitigating and controlling flood disasters, optimising the allocation of water resources, and evaluating the hydrological effects within watersheds. © 2024, The Authors. All rights reserved.

关键词： Watersheds

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Adopting a Hot Film to Measure Thickness of an Ice Layer Under Sweeping Wind

SSRN

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SSRN 2023年

作者： Wang, Feng Zhang, Tengfei Wang, Shanran Department of Civil Engineering Dalian University of Technology Dalian China Tianjin Laboratory of Indoor Air Environmental Quality Control School of Environmental Science and Engineering Tianjin University Tianjin China Wuhan Second Ship Design and Research Institute Wuhan430205 China School of Aeronautic Science and Engineering Beihang University Beijing100191 China Department of Building Environment and Energy Engineering The Hong Kong Polytechnic University Hung Hom Hong Kong

Ice can easily form on low-temperature surfaces. To prevent damage caused by undesirable ice, the presence of ice on a surface together with the ice thickness must be determined. This investigation proposed to measure the thickness of an ice layer under sweeping wind using a hot film and two thermocouples. On the basis of the steady temperature gradient in the ice layer and the solved ice-layer surface temperature from the main stream, the ice layer thickness was obtained. The model required only the heat flux through the ice layer and the measured steady temperature rise at the ice surface adjacent to the heater. The ice thickness determined by the proposed method was compared with that measured with a microcalliper. In addition, CFD was used to generate temperature data to evaluate the proposed method for the ice layer blown by high-speed winds. The results demonstrated that the proposed method could accurately measure the thickness of the ice layer under wind blowing at 5–300 m/s. The relative discrepancy in the inferred ice thickness with the microcalliper-measured thickness was less than 10%, and the accuracy of the method increased with the wind speed. © 2023, The Authors. All rights reserved.

关键词： Wind

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Multidomed superconductivity and tunable orbital-selective pairing in pressurized FeSe with correlation enhanced electron-phonon coupling

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Physical Review B 2025年第22期111卷 L220501-L220501页

作者： Zhizhong Ding Jiaqing Gao Wei Qin Yanming Ma Ping Cui Zhenyu Zhang International Center for Quantum Design of Functional Materials (ICQD) Hefei National Research Center for Physical Sciences at Microscale University of Science and Technology of China Hefei 230026 China Department of Physics University of Science and Technology of China Hefei 230026 China Key Laboratory of Material Simulation Methods and Software of Ministry of Education and State Key Laboratory of Superhard Materials College of Physics Jilin University Changchun 130012 China Hefei National Laboratory University of Science and Technology of China Hefei 230088 China

As a layered material, FeSe provides an ideal platform for realizing high-temperature superconductivity and exploring the microscopic pairing mechanisms. Here, we investigate the behavior of superconductivity and orbital-selective pairing of bulk FeSe under different pressuring schemes within first-principles dynamical mean-field theory (ab-DMFT). We first confirm that the orthorhombic phase is preferred among the layered structures, and the resultant superconducting transition temperature (Tc) is elevated from essentially zero to the experimentally observed order of magnitude only with the inclusion of correlation-enhanced electron-phonon coupling. The vital role of correlation effects is strongly corroborated by our quantitative interpretation of the experimentally observed superconducting dome under hydrostatic pressure. Counter-intuitively, the Tc qualitatively anticorrelates with the correlation strength, as measured by the quasiparticle broadening around the Fermi level. We further investigate the effects of biaxial and uniaxial pressures and predict that uniaxial pressure can induce the emergence of two superconducting domes due to a synergetic effect of structural transitions and a switching of the dominant orbital-selective pairing from dxy to dz2. Collectively, these findings pinpoint the vital role of electron correlations in the phonon-mediated pairing mechanism of bulk FeSe, and the ab-DMFT approach for quantitative evaluation of Tc is expected to find broad applicability in other correlated electron systems.

关键词： Electron-phonon interactions

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Roll Force Model of V-Shaped Variable Thickness Rolling Based on Energy Approach

SSRN

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SSRN 2024年

作者： Wang, Sai Gao, Haitao Wang, Xiaogong Hu, Junhua Yang, Yang Sun, Yinan Lu, Rihuan Hu, Xianlei Liu, Xianghua Li, Changsheng Zhang, Yu Song, Wei Research Institute of Interdisciplinary Innovation Zhejiang Lab Hangzhou311121 China State Key Laboratory of High Performance Complex Manufacturing Light Alloys Research Institute Central South University Changsha410083 China College of Metallurgy and Energy North China University of Science and Technology Tangshan063210 China Wuhan Second Ship Design and Research Institute Wuhan430064 China School of Mechanical Engineering Yanshan University Qinhuangdao066004 China State Key Laboratory of Rolling and Automation Northeastern University Shenyang110819 China

V-shaped Variable Thickness Rolling (V-VTR) serves as a specialized cold rolling method for manufacturing Rolled Profiled Strips (RPS), particularly useful for quickly preparing RPS with large thickness ratios. In the V-VTR process, metal predominantly flows in the lateral direction. However, there is a scarcity of theoretical models for calculating the rolling force in V-VTR, leading to a void in theoretical guidance for both device design and product thickness control. To fill this gap, we introduce a novel mathematical model specifically designed to calculate the V-VTR rolling force, considering the lateral flow of the metal. Initially, the deformation pattern is investigated and subsequently modeled. Then, the models for kinematically permissible velocity and strain fields are developed, and their validity is confirmed through both experimental data and simulation analysis. Incorporating factors like strain energy and frictional work, a formula for V-VTR rolling force is derived based on the upper bound theory. The efficacy of this newly proposed rolling force model is confirmed through experimental testing, which indicates that the formula offers a high degree of accuracy. © 2024, The Authors. All rights reserved.

关键词： Cold rolling

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A three-stage model for the perforation of finite metallic plates by long rods at high velocities

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Defence technology（防务技术） 2019年第3期15卷 409-418页

作者： Yu He Liu-yun Xu He-ming Wen Zheng-cao Lu National Key Laboratory of Shock Wave and Detonation Physics Institute of Fluid Physics CAEP Mianyang 621900 China CAS Key Laboratory for Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei Anhui 230027 China

A three-stage theoretical model is presented herein to predict the perforation of a thick metallic plate struck normally by a long rod at high velocities. The model is suggested on the basis of the assumption that the perforation of a thick metallic plate by a long rod can be divided into three stages:(1) initial penetration;(2) plug formation and (3) plug slipping and separation. Various analytical equations are derived which can be employed to predict the ballistic limit, residual velocity and residual length of the long rod. It is demonstrated that the present model predictions are in good agreement with available experimental results for the perforation of finite steel targets struck normally by steel as well as tungsten alloy long rods at high velocities. It is also demonstrated that the dynamic maximum shear stress of a plate material has strong effect on plug formation and plug thickness which, in turn, exerts considerable influence on the residual velocities and lengths of a long rod at impact velocities just above the ballistic limit.

关键词： Perforation Long rod Finite metallic plate Ballistic limit Residual velocity Residual length

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Multiple Dirac nodal lines in an in-plane anisotropic semimetal TaNiTe5

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Physical Review B 2021年第11期104卷 115158-115158页

作者： Zhanyang Hao Weizhao Chen Yuan Wang Jiayu Li Xiao-Ming Ma Yu-Jie Hao Ruie Lu Zecheng Shen Zhicheng Jiang Wanling Liu Qi Jiang Yichen Yang Xiao Lei Le Wang Ying Fu Liang Zhou Lianglong Huang Zhengtai Liu Mao Ye Dawei Shen Jiawei Mei Hongtao He Cai Liu Ke Deng Chang Liu Qihang Liu Chaoyu Chen Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics Southern University of Science and Technology (SUSTech) Shenzhen 518055 People's Republic of China State Key Laboratory of Functional Materials for Informatics and Center for Excellence in Superconducting Electronics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 People's Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing 100049 People's Republic of China Department of Physics The Hong Kong University of Science and Technology Clear Water Bay Hong Kong People's Republic of China Institute of Applied Physics and Materials Engineering University of Macau Avenida da Universidade Taipa Macau 999078 People's Republic of China Guangdong Provincial Key Laboratory for Computational Science and Material Design Southern University of Science and Technology Shenzhen 518055 People's Republic of China Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and Technology Shenzhen 518055 People's Republic of China

Nodal-line semimetals (NLSMs) contain Dirac-Weyl-type band-crossing nodes extending into shapes of lines, loops, and chains in the reciprocal space, leading to band topology and transport responses. Robust NLSMs against spin-orbit coupling typically occur in three-dimensional and in-plane isotropic materials which have more symmetry operations to protect the line nodes of band crossing, while the possibilities in exfoliatable materials with in-plane anisotropy are rarely discussed. Here, we demonstrate a robust NLSM phase in an exfoliatable in-plane anisotropic nonmagnetic semimetal TaNiTe5. Combining angle-resolved photoemission spectroscopy measurements and first-principles calculations, we reveal multiple Dirac-type nodal lines with fourfold degeneracy in TaNiTe5. Our findings suggest rich physics in structurally anisotropic topological materials and call for further functional exploitation based on them.

关键词： Electronic structure Symmetry protected topological states Topological phases of matter

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The Response of Caisson Induced by Adjacent Spudcan Penetration in Non-Homogeneous Clay

SSRN

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SSRN 2023年

作者： Peng, Xi Qi, Yongle Zhou, Mi Zhang, Xihong Tian, Yinghui Li, Jinhui State Key Laboratory of Subtropical Building Science South China Institute of Geotechnical Engineering South China University of Technology 381 Wushan Road Guangzhou510640 China Whiting School of Engineering Johns Hopkins University 3400 N Charles St BaltimoreMD21218 United States China Energy Engineering Group Guangdong Electric Power Design Institute Co. Ltd. 1 Tianfeng Road Science Town Guangzhou510663 China School of Marine Science and Engineering State Key Laboratory of Subtropical Building Science South China University of Technology 381 Wushan Road Guangzhou510640 China School of Civil and Mechanical Engineering Curtin University Kent Street Bentley6102 Australia Dept. of Infrastructure Engineering The University of Melbourne ParkvilleVIC3010 Australia Shenzhen518055 China

Penetration of spudcan foundations is proven to contribute to the response of adjacent caisson foundations. Installation of offshore wind turbine system (OWT) often requires close-in penetration of spudcan for jack-up, which threatens the safety of OWTs and thus requires proper study. This paper presents an extensive numerical simulation on the responses of a caisson induced by the adjacent spudcan penetration in non-homogenous clay. Large deformation finite elements (LDFE) analysis is performed to study the deformation mechanism of caisson and to quantify its deformation. A numerical model is generated which is validated with previous data in terms of penetration resistance and soil deformation. Then, an extensive parametric study is are conducted to investigate the deformation characteristics of caissons induced by the installation of the adjacent spudcan. Three types of deformation mechanisms of caisson are observed. It is found that the distance between the spudcan and the caisson, the ratio of caisson length over diameter, and the soil property are the key influencing factors on the rotation angle of the caisson. Finally, empirical formulae are proposed for estimating the rotational angle of a caisson, which provide design guidance for construction of caissons for OWTs. © 2023, The Authors. All rights reserved.

关键词： Caissons

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Segregation at prior austenite grain boundaries: the competition between boron and hydrogen

arXiv

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arXiv 2024年

作者： Hachet, Guillaume Tehranchi, Ali Shi, Hao Prabhakar, Manoj Wei, Shaolou Angenendt, Katja Zaefferer, Stefan Gault, Baptiste Sun, Binhan Ponge, Dirk Raabe, Dierk Department of Microstructure Physics and Alloys Design Max-Planck-Institut für Nachhaltige Materialien Düsseldorf40237 Germany Key Laboratory of Pressure Systems and Safety Ministry of Education School of Mechanical and Power Engineering East China University of Science and Technology Shanghai China Department of Materials Royal School of Mines Imperial College London Prince Consort Road LondonSW7 2BP United Kingdom

The interaction between boron and hydrogen at grain boundaries has been investigated experimentally and numerically in boron-doped and boron-free martensitic steels using thermal desorption spectrometry (TDS) and ab initio calculations. The calculations show that boron and hydrogen are attracted to grain boundaries but boron can repel hydrogen. This behavior has also been observed using TDS measurements, with the disappearance of one peak when boron is incorporated into the microstructure. Additionally, the microstructure of both steels has been studied through electron backscattered diffraction, synchrotron X-ray measurements, and correlative transmission Kikuchi diffraction-atom probe tomography measurements. While they have a similar grain size, grain boundary distribution, and dislocation densities, pronounced boron segregation into PAGBs is observed for boron-doped steels. It indicates that boron in PAGBs is responsible for the disappearance of the TDS peaks for the boron-doped steel. Then, the equilibrium hydrogen concentration in different trapping sites has been evaluated using the Langmuir-McLean approximation. This thermodynamic model shows that the distribution of hydrogen is identical for all traps when the total hydrogen concentration is low for boron-free steel. However, when it increases, traps of the lowest segregation energies (mostly PAGBs) are firstly saturated, which promotes failure initiation at this defect type. This finding partially explains why PAGBs are the weakest microstructure feature when martensitic steels are exposed to hydrogen-containing environments. © 2024, CC BY.

关键词： Grain boundaries

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Corrigendum to “A simultaneous corrosion/irradiation facility for testing molten salt-facing materials” [Nucl. Instrum. Methods Phys. Res Sect. B 440 (2019) 54–59]

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Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 2023年 544卷

作者： Weiyue Zhou Kevin B. Woller Guiqiu (Tony) Zheng Peter W. Stahle Michael P. Short Department of Nuclear Science and Engineering Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139 USA Nuclear Reactor Laboratory Massachusetts Institute of Technology 138 Albany St. Cambridge MA 02139 USA

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