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

Experimental Study on the Flow Characteristics of Rod Bundle Under Rolling Motion 滚动运动下棒束流动特性的实验研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-65590

Xin Li, Peiyao Qi, Sichao Tan, Chao Qi, S. Qiao

{"title":"Experimental Study on the Flow Characteristics of Rod Bundle Under Rolling Motion","authors":"Xin Li, Peiyao Qi, Sichao Tan, Chao Qi, S. Qiao","doi":"10.1115/icone28-65590","DOIUrl":"https://doi.org/10.1115/icone28-65590","url":null,"abstract":"\u0000 The floating reactor system will be rolling, heaving and other movements affected by waves, wind, etc. These motions will introduce additional inertial force field into the rod bundle, thus affecting the flow characteristics in the rod bundle channel. In order to study the influence of rolling motion on the flow characteristics of rod bundle, a visualization research of the flow field of rod bundle channel with a pitch-to-diameter ratio of 1.326 was carried out under rolling motion. The results show that under a small driving force, the rolling motion has a significant effect on the flow field in the rod bundle, affecting the velocity distribution in different sub-channels, and there is transverse mixing between adjacent sub-channels. With the increase of driving force, the influence of rolling motion is gradually weakened. The flow field distribution under rolling motion is significantly different from that under pulsating flow. The experimental results show that the influence of rolling motion on the middle sub-channel of the rod bundle channel is small, and the influence on the edge sub-channel is large. The velocity field of the subchannels on both sides of the edge fluctuates periodically, and the wave phase is inverse. This study shows that the flow field variation caused by rolling motion is different from that caused by pulsating flow, and the flow field of fuel assembly in floating reactor system under ocean condition is further studied.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"146 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":"121301784","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

Study on Deposition Motion of Naturally Circulating Particulate Matter in Supercritical Water Based on Factor and Correspondence Analysis 基于因子与对应分析的超临界水中自然循环颗粒物沉积运动研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-63677

Qi Tian, T. Zhou, Ning Chen, J. Chen

{"title":"Study on Deposition Motion of Naturally Circulating Particulate Matter in Supercritical Water Based on Factor and Correspondence Analysis","authors":"Qi Tian, T. Zhou, Ning Chen, J. Chen","doi":"10.1115/icone28-63677","DOIUrl":"https://doi.org/10.1115/icone28-63677","url":null,"abstract":"\u0000 It is very important to study the deposition of particles in natural circulation of supercritical water to ensure the safe and stable operation of supercritical water reactor. The data of natural circulation loop calculated by ANSYS-CFX simulation software were analyzed by factorial analysis method, and the effects of axial distance, initial particle volume fraction, heating power and particle size on particle deposition were obtained. The results show that the contribution rate of particle size to the deposition rate is the largest, about 36.3%, and the contribution rate of initial particle concentration to the deposition rate is about 15.1%; the interaction between axial distance and heating power is the most obvious, and the interaction effect is the pipe temperature distribution. Through correspondence analysis, the main influencing factors of particle deposition rate at each level were analyzed. The results show that: when the deposition rate is small, the small change of axial distance will also have a greater impact on the deposition of particles; when the deposition rate is further increased, the change of initial particle volume fraction will significantly affect the deposition of particles; when the deposition rate is large, the particle size plays a leading role in the deposition of particles. Both of the two analysis methods show that: in the influence on the deposition of particles in supercritical water natural circulation, the influence degree is particle size > concentration > axial distance > heating power. Based on the two analysis methods, an analysis regression model is established and the volume proportion of particles in natural circulation is predicted.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"2 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":"122722725","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

Effects of Non-Condensable Gas on Characteristics of Natural Circulation Flow of Isolation Condenser 不可冷凝气体对隔离冷凝器自然循环流动特性的影响

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-64595

Tetsuya Takada, Yasunori Yamamoto, K. Ono

引用次数: 0

Research on the Air-Water Flow Regime and Characteristics in Rectangular Channel 矩形通道内空气-水流动规律及特性研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-66238

Qingche He, L. Pan, Luteng Zhang, Meiyue Yan, Wangtao Xu

{"title":"Research on the Air-Water Flow Regime and Characteristics in Rectangular Channel","authors":"Qingche He, L. Pan, Luteng Zhang, Meiyue Yan, Wangtao Xu","doi":"10.1115/icone28-66238","DOIUrl":"https://doi.org/10.1115/icone28-66238","url":null,"abstract":"\u0000 Two-phase Flow is widely involved in reactor design and is directly relevant to reactor safety. However, the flow regime in narrow rectangular channels still needs further study because it has a considerable difference from tube and bundle channels. To investigate the two-phase flow regime and interfacial structure characteristics, the air-water experiment with an adiabatic vertical channel of 4 × 66 × 1800, 6 × 66 × 1800 mm have been conducted under atmosphere pressure condition. The impedance void meter was used to measure the global void fraction in narrow rectangular channels. A high-speed camera was used to record the profiles of the flow regime. The flow regime was identified by the random forest clustering algorithm based on a training sample. The profiles of different parameters, including void fraction, pressure loss at Z/D = 150, were analyzed in this paper. Furthermore, based on the parameters’ distribution, the regime transition criteria in narrow rectangular channels were discussed. It is shown that the transition from bubble to slug flow always occurred when the average void fraction is 0.17–0.2. The transition value is 0.57–0.62 when the slug Flow changes to the churn-turbulent Flow and 0.78–0.8 from churn-turbulent to annular Flow. The constant used in the Lockhart-Martinelli correlation is found to calculate the frictional pressure drop in a rectangular channel. Furthermore, the drift-model applied to the rectangular channel is verified.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"81 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":"129116858","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 on Measurement of Annular Flow Film Thickness in Vertical Narrow Rectangular Channel 垂直窄矩形通道环形流膜厚度测量的实验研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-63469

Antai Liu, Haifeng Gu, Fuqiang Zhu, Chang-qi Yan

{"title":"Experimental Study on Measurement of Annular Flow Film Thickness in Vertical Narrow Rectangular Channel","authors":"Antai Liu, Haifeng Gu, Fuqiang Zhu, Chang-qi Yan","doi":"10.1115/icone28-63469","DOIUrl":"https://doi.org/10.1115/icone28-63469","url":null,"abstract":"\u0000 As a key physical parameter in annular flow, liquid film thickness is crucial to study the behavior characteristics about gas-liquid interface under annular flow conditions. In this study, the narrow rectangular channel is taken as the research object, and air-water were used as the media to conduct annular flow experiments under atmospheric pressure. The cross-sectional area of the narrow rectangular channel is 70mm × 2mm. The PCB liquid film sensor can realize multi-point measurement of liquid film thickness. A total of 10 × 16 measuring points are arranged in rows and columns on the surface of the channel, with a spatial resolution of 4.4mm × 4.4mm and a measurement speed of 1000 frames per second. The results show the fluctuation of liquid film is dominated by the ripple wave at low superficial liquid velocity. The frequency distribution of film thickness becomes sharper because of the increase of gas flow, i.e. the interfacial surface becomes smoother. The liquid film will become thinner with the increase of gas flow, but the effect is reduced when the gas flow reaches a certain value. The liquid film will thicken and the number of disturbance waves will increase as the increase of the liquid flow.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"58 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":"124419637","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 Passive Tube Condensation With Non-Condensable Gas Using Heat and Mass Analogy Model 用热质量类比模型分析非冷凝气体被动管内冷凝

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-65829

Ugur Cotul, S. Revankar

{"title":"Analysis of Passive Tube Condensation With Non-Condensable Gas Using Heat and Mass Analogy Model","authors":"Ugur Cotul, S. Revankar","doi":"10.1115/icone28-65829","DOIUrl":"https://doi.org/10.1115/icone28-65829","url":null,"abstract":"\u0000 In this study, we used the heat and mass analogy model to be able to predict the heat transfer properties of a condenser tube operating in passive mode. The most important advantage of analogy model comparing boundary layer model is simplicity and fast computation, that’s why it can be applied to various engineering problems for many cases. The heat and mass analogy model is based on the heat transfer balance between liquid film and gas mixture area. The main problem for the liquid film region is the heat transfer coefficient (HTC) which is affected negatively in the presence of non-condensable gas. Therefore, our main goal is to increase the HTC and condensation heat transfer rate by updating the analogy code. In the gas-vapor mixture region, heat transfer mainly occurred as latent condensation and sensible heat transfer. In order to maintain this balance between the mixture and liquid film, the interface temperature is iterated. After defining a specified tolerance value of the heat and mass analogy model codes, this iteration process was started to be used at the entrance of a condenser tube. The gas and vapor mixture is considered to be saturated at the liquid/gas interface in the heat and mass transfer analogy model. Via boundary layer study of species concentration and energy balance, the non-condensable gas effect on condensation is added into the equation. For the condensation heat transfer coefficient of turbulent vapor flow associated with laminar condensate, numerical predictions were made and they were satisfactory. The predictions were compared with the experimental data from the literature to be able to test the model. Non-condensable gas mass fraction and vapor-non-condensable mixture temperature were presented in the form of radial and axial profiles.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"215 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":"130677591","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

Study on the Modeling and Simulation of the Horizontal Steam Generator in VVER-1000 VVER-1000卧式蒸汽发生器建模与仿真研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-64456

Ru Zhang, Junyan Qing, Xiaolong Bi, Guanfu Jiang, Peiwei Sun, Xinyu Wei

{"title":"Study on the Modeling and Simulation of the Horizontal Steam Generator in VVER-1000","authors":"Ru Zhang, Junyan Qing, Xiaolong Bi, Guanfu Jiang, Peiwei Sun, Xinyu Wei","doi":"10.1115/icone28-64456","DOIUrl":"https://doi.org/10.1115/icone28-64456","url":null,"abstract":"\u0000 Steam Generator (SG) is one of the main components of the power cycle in pressurized water reactor (PWR), and it is the hub of primary coolant circuit and secondary circuit, so the thermal hydraulic analysis of the SG is crucial in the system design and safety analysis of the PWR. The horizontal steam generator (HSG) is one of the main types SG in the PWR nuclear power plant (NPP), and its advantages are that it has more secondary side water capacity and good safety and reliability. The VVER-1000 is a PWR with a thermal power of 3000 MW, and has four HSGs for four loops. The RELAP5 has been used to model the VVER-1000’s HSG and performs the analysis described in this paper. The HSG tube bundle is modeled by three horizontal channels, and the steam control volumes above the heat transfer tube bundle are modeled with three volumes. The steam space is modeled as a steam separator and the steam reception shield is the dryer. The HSG secondary side downcomers are represented with a separate component to provide the power of the natural circulation. To verify the accuracy of the model, three different typical conditions are simulated. The simulation results show that the model built in this paper can correctly simulate the operation of the HSG in VVER-1000.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"40 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":"133832112","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

Study on Local Sub-Cooling Boiling in the Vertical Upward Pipe 垂直向上管内局部过冷沸腾的研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-61374

Menglong Liu, Zhen Zhang, Xingtuan Yang

{"title":"Study on Local Sub-Cooling Boiling in the Vertical Upward Pipe","authors":"Menglong Liu, Zhen Zhang, Xingtuan Yang","doi":"10.1115/icone28-61374","DOIUrl":"https://doi.org/10.1115/icone28-61374","url":null,"abstract":"\u0000 In the heat transfer pipes of nuclear reactors with complex mass and heat exchange, there exists phenomenon of local sub-cooling boiling. Based on the Eulerian two-fluid model, this paper studied the local sub-cooling boiling phenomenon in the vertical upward pipe at a pressure of 4.5MPa. Firstly, a closed sub-cooling boiling model was built to make comparison with the existing experimental results of Bartolomei, the result of which is in great agreement with the experimental data. What’s more, the parameters of the experimental working conditions were expanded, it helped to analyze data that could not be directly measured in the experiment. The physical mechanism behind data distribution law mainly included the influence of the wall bubble departure diameter, the wall bubble departure frequency, and nucleation density. It is found that the RPI model has a good predictive ability for the liquid temperature field. The nucleation density model corresponding to KI combined with the wall departure diameter model KI can well predict the distribution of the void fractions in the pipe. Finally, the influence on heat and mass transfer of heating power along the pipe was analyzed.\u0000 This paper put forward suggestions for the modification of the sub-cooling boiling model to help it predict the distribution of bubbles in the main flow region more precise.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"88 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131672697","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

Study on Deteriorated Heat Transfer in Upward Flow of Supercritical Water in a 1-M Vertical Bare Tube 超临界水在1m垂直裸管内向上流动的变质换热研究

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-64530

N. Dort-Goltz, I. Pioro, J. McKellar

{"title":"Study on Deteriorated Heat Transfer in Upward Flow of Supercritical Water in a 1-M Vertical Bare Tube","authors":"N. Dort-Goltz, I. Pioro, J. McKellar","doi":"10.1115/icone28-64530","DOIUrl":"https://doi.org/10.1115/icone28-64530","url":null,"abstract":"\u0000 SuperCritical Water-cooled Reactors (SCWRs) represent potential improvements over traditional water-cooled reactors in many respects, including thermal efficiency. These reactors are still under development, however, thermalhydraulics data needed for their design are lacking. Experimentation is complex and costly. In spite of a large number of experiments in long bare tubes (pipes) cooled with SCW, developing SCWR concepts requires experimental data in bundle geometries cooled with SCW, which are usually shorter and will have smaller hydraulic-equivalent diameters.\u0000 As a first step, tests have been conducted by others on heat transfer in short, vertical bare tubes cooled with the upward flow of SCW. The objective of this work is to analyze that collected data with particular attention to the Deteriorated Heat Transfer (DHT) regime. The DHT regime is characterized by reduced Heat Transfer Coefficients (HTCs) and consequently increased wall temperatures. As such, it represents a hazard to the safe operation of a Nuclear Power Plant (NPP).\u0000 The results of this analysis indicate that DHT did occur in each of the tests analyzed, often seen as a gradual decrease in HTC along the heated length, but occasionally as a sharp “dip”. The DHT can occur along the heated length, when the bulk-fluid temperature is close to or within the pseudocritical region. The results also confirmed that the Dittus-Boelter correlation does not adequately predict HTCs within the pseudocritical region. Two other applied correlations (Gupta et al. and Mokry et al.) performed better, but neither was able to predict the occurrence of the DHT.\u0000 The results of this analysis will be of use to designers and developers of SCWRs, and can help to plan future experiments.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"60 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":"124195244","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: 1

Robustness Analysis and Improvement of Fault Diagnosis Model for Nuclear Power Plants Based on Random Forest 基于随机森林的核电厂故障诊断模型鲁棒性分析及改进

Volume 4: Student Paper Competition Pub Date : 2021-08-04 DOI: 10.1115/icone28-64109

Jiangkuan Li, Meng Lin

{"title":"Robustness Analysis and Improvement of Fault Diagnosis Model for Nuclear Power Plants Based on Random Forest","authors":"Jiangkuan Li, Meng Lin","doi":"10.1115/icone28-64109","DOIUrl":"https://doi.org/10.1115/icone28-64109","url":null,"abstract":"\u0000 With the development of artificial intelligence technology, data-driven methods have become the core of fault diagnosis models in nuclear power plants. Despite the advantages of high flexibility and practicability, data-driven methods may be sensitive to the noise in measurement data, which is inevitable in the process of data measurement in nuclear power plants, especially under fault conditions. In this paper, a fault diagnosis model based on Random Forest (RF) is established. Firstly, its diagnostic performance on noiseless data and noisy data set containing 13 operating conditions (one steady state condition and 12 fault conditions) is analyzed, which shows that the model based on RF has poor robustness under noisy data. In order to improve the robustness of the model under noisy data, a method named ‘Train with Noisy Data’ (TWND) is proposed, the results show that TWND method can effectively improve the robustness of the model based on RF under noisy data, and the degree of improvement is related to the noise levels of added noisy data. This paper can provide reference for robustness analysis and robustness improvement of nuclear power plants fault diagnosis models based on other data-driven methods.","PeriodicalId":108609,"journal":{"name":"Volume 4: Student Paper Competition","volume":"60 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":"126164700","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