Volume 4: Student Paper Competition最新文献_第2页

Study on Laminar Turbulent Transition in Square Arrayed Rod Bundles 方阵棒束层流湍流转捩研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-65706

C. S. Dutra, E. Merzari

{"title":"Study on Laminar Turbulent Transition in Square Arrayed Rod Bundles","authors":"C. S. Dutra, E. Merzari","doi":"10.1115/icone28-65706","DOIUrl":"https://doi.org/10.1115/icone28-65706","url":null,"abstract":"\u0000 The study of coolant flow behavior in rod bundles is of relevance to the design of nuclear reactors. Although laminar and turbulent flows have been researched extensively, there are still gaps in understanding the process of laminar-turbulent transition. Such a process may involve the formation of a gap vortex street as the consequence of a related linear instability.\u0000 In the present work, a parametric study was performed to analyze the spatially developing turbulence in a simplified geometry setting. The geometry includes two square arrayed rod bundle subchannels with periodic boundary conditions in the cross-section. The pitch-to-diameter ratios range from 1.05 to 1.20, and the length of the domain was selected to be 100 diameters. No-slip condition at the wall, and inlet-outlet configuration were employed. Then, to investigate the stability of the flow, the Reynolds number was varied from 250 to 3000. The simulations were carried out using the spectral-element code Nek5000, with a Direct Numerical Simulation (DNS) approach. Data were analyzed to examine this Spatio-temporal developing instability. In particular, we evaluate the location of onset and spatial growth of the instability.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133336060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low Dose Assessment Uncertainty Analysis for Landauer® nanoDot™ OSLDs Landauer®nanoDot™osld的低剂量评估不确定度分析

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-65591

E. Aras, R. Hayes

{"title":"Low Dose Assessment Uncertainty Analysis for Landauer® nanoDot™ OSLDs","authors":"E. Aras, R. Hayes","doi":"10.1115/icone28-65591","DOIUrl":"https://doi.org/10.1115/icone28-65591","url":null,"abstract":"\u0000 This study aims to low-level background range measurements of commercial OSLDs. This work is the initial step to put a framework to detect any illicit nuclear activities in any nuclear facility at any time. The idea in this framework is to utilize already placed OSLDs in the facility which are normally read-out periodically. The results of these measurements could be distinguishable from the background radiation since this paper shows how the background dose with its statistical fluctuation provide detection limits in these applications. To do this, we measured dosimeters in two ways; without removal or replacement and full removal for each measurement. As a result of measurements, the initial dose, bleaching constant, and background dose was evaluated for different measurements. ANOVA was applied to all measurements and all measurements considered a measurement data set to analyze results. Consequently, we observed no statistically significant difference in these different kinds of measurement approaches relative to the total propagated uncertainty in any given dose estimate. This shows a passive detection can be verified with iterative measurements to improve statistics without compromising data quality when coupled with dose levels of potential interest serves to advance this potential nonproliferation application.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115079796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental Study of Characteristics of Flow Field in Rod Bundle Channel Under Blocking Conditions 阻塞条件下棒束通道流场特性的实验研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-65498

X. Yu, Yonghao Zhang, Peiyao Qi, Yusheng Liu, S. Qiao, Sichao Tan

{"title":"Experimental Study of Characteristics of Flow Field in Rod Bundle Channel Under Blocking Conditions","authors":"X. Yu, Yonghao Zhang, Peiyao Qi, Yusheng Liu, S. Qiao, Sichao Tan","doi":"10.1115/icone28-65498","DOIUrl":"https://doi.org/10.1115/icone28-65498","url":null,"abstract":"\u0000 The rod bundle fuel is characterized by compact structure and narrow flow passage. The fragments and corrosion products, flowing with the coolant, can cause local blockage accident, threaten the integrity of the fuel cladding. Therefore, it is necessary to use the Particle Image Velocimetry (PIV) to visualize and measure the flow fields downstream of the blockages. The results show that partial blockages will cause flow reversal. In the backflow zone, vortices are generated downstream of the blockage, causing increase in the resistance. The length of backflow zone increases with the increase of the Reynolds number. The wake area formed downstream of the blockage presented periodic changes with the time and the period is about 0.8s. For the blockage of the interior subchannels, in the backflow zone, two rows of asymmetrically distributed vortices, and the vortices interfere with each other and cause squeeze deformation. For the blockage of the side and corner sub-channels, the formed vortices have irregular shape and nonuniformed distribution, and the flow field is more complex and changeable. This is believed to be caused by the high intensity turbulence and the influence of the wall.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125937869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulation Analysis and Optimization of Lubricating Oil System 润滑油系统仿真分析与优化

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-64547

Qiong Wu, Jianjun Wang, Jingming Chen, Pengzheng Li

{"title":"Simulation Analysis and Optimization of Lubricating Oil System","authors":"Qiong Wu, Jianjun Wang, Jingming Chen, Pengzheng Li","doi":"10.1115/icone28-64547","DOIUrl":"https://doi.org/10.1115/icone28-64547","url":null,"abstract":"\u0000 Based on the one-dimensional simulation model of lubricating oil system is established and analyzed by using FLOWMASTER software, this paper proposes a new method of optimizing lubricating oil system by PID technology. Ensure that the configuration requirements and control strategies of the relevant accessories of the simulation model are satisfied with the design requirements. Firstly, by simulating lubricating oil pressure fluctuation and lubricating oil flow distribution under Open/Close Valve in different opening and closing time, the optimal opening/closing time of Open/Close Valve is determined to be 0.2 s and 0.5 s respectively. Secondly, by writing the controller script file combined with a controller to realize automatic unloading relief valve simulation, determine the relief valve pressure regulating range of 0∼0.38 MPa, For precision of constant pressure valve of oil spill, the simulation results show that the average 10 m3/h flow caused by pressure changes of about 0.06 MPa. Under the flow sudden change signal of about 40 m3/h, the maximum pressure change is less than 0.1 MPa. Through the simulation results, it is found that most of the lubrication parts in the original design have the phenomenon of flow redundancy, which causes unnecessary pump power loss. The system is optimized by PID technology. By comparing the simulation results before and after optimization, it is found that the speed of constant displacement pump could be changed in time by PID controller, and the flow redundancy could be improved significantly, so the lubricating oil system could be lower consumption and achieve the purpose of optimization.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128941295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of Friction Factor of Two-Phase Flow in Helically Coiled Tubes 螺旋螺旋管内两相流摩擦因数分析

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-64356

B. Jiang, Zhiwei Zhou, Y. Ji

{"title":"Analysis of Friction Factor of Two-Phase Flow in Helically Coiled Tubes","authors":"B. Jiang, Zhiwei Zhou, Y. Ji","doi":"10.1115/icone28-64356","DOIUrl":"https://doi.org/10.1115/icone28-64356","url":null,"abstract":"\u0000 With compact structure and enhanced heat transfer capacity, helical-coiled once through steam generators (HTSGs) are widely used in the small modular reactors (SMRs). Nevertheless, the inside centrifugal forces make the flow more complicated, and increase the frictional pressure drop, which is closely related to the dual test of alternating thermal stress and flow instability. Therefore, the analysis of the friction factor in helically coiled tubes is significant to the efficient and safe operation of HTSGs.\u0000 While the friction factor of single-phase flow in helically coiled tubes was fully studied and extensive correlations have been validated by a large amount of experimental data, the friction factor of two-phase flow still lacks feasible prediction due to its much more complexity. The existed correlations of two-phase flow in helically coiled tubes are mostly based on specified experimental parameters, so the applicable range is limited. Few scholars have tried to extend these correlations to broader applicability, but the trivial applicable range is unsuitable for program development or engineering design, which needs an accurate prediction of friction factor in a wider range.\u0000 In this paper, existing frictional pressure drop correlations are investigated. The accuracy of single-phase frictional pressure drop correlations is verified through the comparison of calculation results. Since the known experimental data cannot cover a wide range of parameters, two assumptions are proposed, and the rationality is verified through the existing experimental data and calculation analysis. Based on the two assumptions and calculation, a set of calculation correlations for frictional pressure drop of two-phase flow in helically coiled tubes are proposed. The accuracy of this calculation model is validated by experimental data. The scope of application of this model is: D / d = 15–100, P = 0.12–6.3MPa, G = 200–1500kg / m2s, which is sufficient to support the design and operation of steam generators and the development of the simulation programs.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125539338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A 3D Numerical Simulation on Heat Transfer Behavior in Eagle ID1 In-Pile Test Using Finite Volume Particle Method 基于有限体积颗粒法的Eagle ID1桩内试验传热特性三维数值模拟

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-61469

Tingan Zhang, K. Morita, Xiaoxing Liu, Wei Liu, K. Kamiyama

{"title":"A 3D Numerical Simulation on Heat Transfer Behavior in Eagle ID1 In-Pile Test Using Finite Volume Particle Method","authors":"Tingan Zhang, K. Morita, Xiaoxing Liu, Wei Liu, K. Kamiyama","doi":"10.1115/icone28-61469","DOIUrl":"https://doi.org/10.1115/icone28-61469","url":null,"abstract":"\u0000 The EAGLE in-pile ID1 test was performed by Japan Atomic Energy Agency to demonstrate the effectiveness of fuel discharge from a fuel subassembly with an inner duct structure during a core disruptive accident in a sodium-cooled fast reactor. The experimental results suggested that early duct wall failure observed in the test was initiated by high heat flux from the molten pool of fuel and steel mixture, and the post-test numerical calculation and analyses showed that the high thermal load may be enhanced effectively by molten steel with a rather high thermal conductivity. In this study, to overcome weakness in conventional fluid-dynamic calculations, we adopted a fully 3D Lagrangian approach based on the finite volume particle method to analyze the mechanisms of heat transfer from the molten pool to the duct wall in the ID1 test. A series of behaviors representing pin disruption, molten pool formation, as well as the mixing and separation of molten steel and fuel in the pool was simulated to investigate their effects on molten pool-to-duct wall heat transfer. The present 3D particle-based simulation, which moderated some inherent defects in our previous 2D calculations, clarified that direct contact of the solid fuel with nuclear heat and liquid steel near the duct wall can expose the duct wall to a large thermal load, which led to the duct wall failure in the experiment.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121524391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Vertical-Downward Two-Phase Flow Regime Identification by Probabilistic Neural Network (PNN) and Nonlinear Support Vector Machine (SVM) 基于概率神经网络(PNN)和非线性支持向量机(SVM)的垂直向下两相流型识别

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-65467

Wenyi Zhong, S. Qiao, Hao Sijia, Xupeng Li, Sichao Tan

{"title":"Vertical-Downward Two-Phase Flow Regime Identification by Probabilistic Neural Network (PNN) and Nonlinear Support Vector Machine (SVM)","authors":"Wenyi Zhong, S. Qiao, Hao Sijia, Xupeng Li, Sichao Tan","doi":"10.1115/icone28-65467","DOIUrl":"https://doi.org/10.1115/icone28-65467","url":null,"abstract":"\u0000 The present study proposes a new feature extraction method based on non-stationary conductivity probe signals. Two types of discriminative network models, i.e., the probabilistic neural network (PNN) and nonlinear support vector machine (SVM), are established for flow regime identification using small sample sets. The eigenvectors are composed of 16 feature quantities obtained by wavelet packet decomposition (WPD) and 8 feature quantities in the time-domain derived from the reconstructed low-frequency signals. The 8 features include maximum, minimum, standard deviation, arithmetic mean, kurtosis, peak factor, impulse factor and margin factor. The signals are normalized based on features rather than samples before flow regime identification. In the current study, WPD results show that the conductivity probe signals in two-phase flow are mostly in low frequency. The identification accuracy of the nonlinear SVM is 90.47%, which is better than 83.33% by the PNN method. This study verifies the superiority of nonlinear SVM in solving small samples and nonlinear flow regime classification problems. However, the accuracy of flow regime identification near flow regime transitional boundaries still remains questionable and needs further improvement.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133704724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Research on Optimization and Verification Method of Sensor Arrangement in the Chemical and Volume Control System 化学和体积控制系统中传感器布置的优化与验证方法研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-65466

Zhou Gui, Hang Wang, M. Peng

{"title":"Research on Optimization and Verification Method of Sensor Arrangement in the Chemical and Volume Control System","authors":"Zhou Gui, Hang Wang, M. Peng","doi":"10.1115/icone28-65466","DOIUrl":"https://doi.org/10.1115/icone28-65466","url":null,"abstract":"\u0000 In order to avoid the nuclear accidents during the operation of nuclear power plants, it is necessary to always monitor the status of relevant facilities and equipment. The premise of condition monitoring is that the sensor can provide sufficient and accurate operating parameters. Therefore, the sensor arrangement must be rationalized.\u0000 As one of the nuclear auxiliary systems, the chemical and volume control system plays an important role in ensuring the safe operation of nuclear power plants. There are plenty of sensor measuring points arranged in the chemical and volume control system. These sensors are not only for detecting faults, but also for running and controlling services.\u0000 Particle swarm algorithm has many applications in solving the problem of sensor layout optimization but the disadvantage of the basic particle swarm optimization algorithm is that the parameters are fixed, the particles are single, and it is easy to fall into the local optimization. In this paper, the basic particle swarm optimization algorithm is improved by Non-linearly adjusting inertia weight factor, asynchronously changing learning factor, and variating particle. The improved particle swarm optimization algorithm is used to optimize the sensor placement.\u0000 The numerical analysis verified that a smaller number of sensors can meet the fault detection requirements of the chemical and volume control system in this paper, and Experiments have proved that the improved particle swarm algorithm can improve the basic particle swarm algorithm, which is easy to fall into the shortcomings of local optimization and single particles. This method has good applicability, and could be also used to optimize other systems with sufficient parameters and consistent objective function.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114829843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Research on Eccentricity Performance of Capacitance Rod Position Measurement Sensor for Measuring Non-Metallic Rod 非金属棒测量电容杆位传感器偏心性能研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-62370

Yanlin Li, Benke Qin, H. Bo

{"title":"Research on Eccentricity Performance of Capacitance Rod Position Measurement Sensor for Measuring Non-Metallic Rod","authors":"Yanlin Li, Benke Qin, H. Bo","doi":"10.1115/icone28-62370","DOIUrl":"https://doi.org/10.1115/icone28-62370","url":null,"abstract":"\u0000 Rod position measurement sensor is the key equipment of control rod hydraulic drive line, the measurement accuracy of the sensor is directly related to the safety and reliability of the reactor. Capacitance rod position measurement sensor is generally composed of excitation and detection electrodes, ceramic tube, outer shielding layer and measuring rod. For the double helix capacitance rod position measurement sensor with non-metallic measuring rod, the static characteristic experiment of the sensor was completed, the finite element method was used to establish the calculation model and the model was verified by the experimental results. By the calculation model, the influence of electrode angle, pitch, thickness and relative permittivity of ceramic tube on the eccentricity error of the sensor was systematically analyzed, the optimal combination of design parameters were obtained by orthogonal test method. The results show that the calculation results are in good agreement with the experimental results, the eccentricity error can be reduced by reducing the electrode angle, increasing the electrode pitch, increasing the thickness and reducing the relative permittivity of the ceramic tube. The design scheme of the sensor obtained by the orthogonal test can greatly reduce the eccentricity error and realize the requirement of rod position measurement without losing step. The research results provide guidance for the design and optimization of capacitance rod position measurement sensor.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125087750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Anomaly Detection of Electric Gate Valve Based on Multi-Kernel Support Vector Machine 基于多核支持向量机的电动闸阀异常检测

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-64766

Jing Luo, Hang Wang, M. Peng

引用次数: 0