核动力工程

Calculation and Analysis of Xenon Poison Effect Curve in HFETR

Wang Hao, Liu Shuiqing, Ma Liyong, Yang Bin, Kang Changhu

2016, 37(1): 1-3. doi: 10.13832/j.jnpe.2016.01.0001

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Abstract:
Numerical method is applied in this paper. By means of the improvement of program, the xenon effect curves under different working conditions on the basis of loading scheme in some cycle of HFETR is studied and calculated. Also, the xenon poison effect curves after scram on the conditions that HFETR operates with different power but the same integral power and operates with different power and different integral power is obtained. The results of calculation and study in this paper have been applied to the operation of HFETR successfully.

Analysis of Moderator Temperature Effect for PBR of SNTP

Jiang Duoyu, Jiang Xinbiao, Wang Lipeng

2016, 37(1): 4-7. doi: 10.13832/j.jnpe.2016.01.0004

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The moderator temperature effect is positive of the particle bed reactor（PBR） model of SNTP, which will have a bad influence on the core safety. The changes of neutron spectra of reactor core, neutron production rates, neutron absorption rates and leakage rates at different ⁷LiH moderator temperature were analyzed with the method of neutron balance by using MCNP code based on the PBR model. The results show that when ⁷LiH temperature rises, neutron losing rates, including neutron absorption rates and leakage rates, increases obvious larger than that for neutron production rates, which caused PBR core presents positive moderator temperature effect, especially when it at lower temperature.

Analysis of Complex Nuclide Chain Equation Calculation Based on Different Method

Tang Songqian, Xiao Feng, Tan Yi, Wei Shuping

2016, 37(1): 8-12. doi: 10.13832/j.jnpe.2016.01.0008

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Depletion calculation of a large number of isotopes plays a very important role in many fields, and ORIGEN-S is the most widely used complex nuclide chain equation calculation code. In this paper, the theory of ORIGEN-S is presented, the time-dependent burnup matrix is explorted and solved using Chebyshev rational approximation method. Results comparing with ORIGEN-S show that, for most of the nuclides, the difference between two methods is quite small, but because ORIGEN-S assumes that the short-lived nuclide is in balance with its long-lived precursor, the result of some nuclides can be conservative, and the deeper the depletion the smaller the difference.

Application of Diagonally Implicit Runge Kutta in Point Kinetics

Zhang Zhizhu, Cai Yun, Peng Xingjie, Li Qing, Qin Dong

2016, 37(1): 13-17. doi: 10.13832/j.jnpe.2016.01.0013

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The stiffness of point kinetics is very strong, while it usually takes a lot of time to solve by using full implicit Runge Kutta（FIRK）. Diagonally Implicit Runge Kutta（DIRK） is a useful tool like FIRK to solve the stiff differential equations, while it greatly reduces the computation compared with FIRK. By embedded lower order Runge Kutta, the time step-size adaptation technique is implemented, which improves the computation efficiency of DIRK. Through three typical cases with step, ramp and sinusoidal reactivity insertions, it shows that the results obtained by DIRK are in good agreement with other available results and DIRK can give far more accurate results than θ method at the same computation cost, especially in the case of fast ramp reactivity insertion.

Theoretical Research on DNB-type Critical Heat Flux with Non-Uniform Axial Heat Flux Distribution

Zhao Dawei, Liu Wenxing, Xiong Wanyu, Zan Yuanfeng, Yang Zumao

2016, 37(1): 18-22. doi: 10.13832/j.jnpe.2016.01.0018

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Based on the liquid sublayer dryout mechanism, an improved mechanistic DNB-type critical heat flux（CHF） model has been developed for non-uniform axial heat flux distribution. In this DNB-type critical heat flux model, the non-uniform heat flux in axial is taken into account of upstream memory effect on thermalhydrlics characters at boiling crisis point; the boiling crisis is triggered when the liquid sublayer underneath vapor blanket is completely dried out by the local heat flux on the wall; and the position of boiling crisis is confirmed by comparing the CHF predictions at each potential boiling crisis points. The prediction results of the present CHF model and empirical correlations with correction factors are verified by non-uniform heating CHF experimental results, which are obtained with inlet-peak, center-peak and outlet-peak power profiles. The comparisons show the present model has more reasonable capability on predicting DNB-type CHF and boiling crisis position under non-uniform heating condition than the correction factor method.

Numerical Investigation of Subcooled Flow Boiling Based on Experimental Data in Vertical Rectangular Narrow Channel

Chen Weihong, Yang Lixing, Zhang Hong

2016, 37(1): 23-27. doi: 10.13832/j.jnpe.2016.01.0023

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This paper proposes and discusses a new wall boiling model developed based on our previous experimental work for the 2mm narrow rectangular channel. The new model includes the active nucleation site density, bubble departure diameter, bubble departure frequency and the onset of nucleate boiling（ONB） sub-models. The thermal-hydraulics of the narrow channel was separately simulated by the new model and CFX model under specific experimental conditions. The simulation results of wall temperature and average temperature were compared with experiment data in good agreement. The difference of three main correlations of two models and the ONB sub-model influence on the result were discussed. The results show that the NEW model with ONB sub-model provides better predictions of the thermal-hydraulics in the narrow channel.

Evaluation and Analysis of Forced Convection Heat Transfer Correlations for Supercritical Carbon Dioxide in Tubes

Huang Yanping, Liu Shenghui, Liu Guangxu, Wang Junfeng, Zan Yuanfeng, Lang Xuemei

2016, 37(1): 28-33. doi: 10.13832/j.jnpe.2016.01.0028

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This paper presents a review of typical heat transfer correlations for S-CO₂, and all of these reviewed correlations were preliminarily evaluated based on amounts of experimental data in published literatures. The results show that there exists superior difference between the predicted and experimental Nusselt numbers in the near critical region, and the predicting ability of these correlations are limited in the stage of deteriorated heat transfer recovery. The correlation of Dong Eok Kim and Moo Hwan Kim gives the best agreement with the test data used, with 84.53% of the predicted Nusselt numbers within a margin of error of ±30%. We also carried out an analysis on the structure of the correlations based on the former evaluation.

Study on Steam Condensation Model of A PRS Heat Exchanger

Rao Yuxian, Yu Lei, Fu Shengwei

2016, 37(1): 34-37. doi: 10.13832/j.jnpe.2016.01.0034

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Steady-state calculations are performed using RELAP5/MOD3.2 code for a test facility which has the same size as one type of secondary-side passive residual heat removal system. In some conditions there are obvious differences between calculation results and experimental data. Thereby, the steam vertical in-tube condensation models for laminar and turbulent conditions in RELAP5 code are improved by considering the interfacial shear stress between vapor and liquid film and high system pressure, respectively. Steady-state and transient calculations are performed using the improved RELAP5 code for the test facility. The simulation results give a good agreement with the experimental data.

Experimental Research of Critical Heat Flux under Uniform Heating and Circumferential Nonuniform Heating in Vertical Circular Channel

Peng Jinfeng, Xu Jianjun, Huang Yanping, Liu Wenxing, Huang Hongwen, Peng Shuming

2016, 37(1): 38-42. doi: 10.13832/j.jnpe.2016.01.0038

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In this paper, the critical heat flux（CHF） experiment in uniform heated and circumferential nonuniform heated vertical channels is developed for the sub-critical energy blanket in the fission-fusion hybrid energy system. The experiment forecast correlation, based on the critical heat flux experiment in the the uniform heated vertical channel, is obtained. The accuracy and reliability of these experiment correlations are proved by statistics analysis and comparison with the present correlations. Based on this experiment correlation, the effect of the circumferential nonuniform heating on the critical heat flux is compared. The experiment result shows that the effect of the mass flux on CHF in nonuniform heated condition is less than that in the uniform heated condition. The CHF of nonuniform channel is lower than that of the uniform channel while the quality is low, otherwise, is higher than that in the uniform channel while the quality is high. The rate of CHF in the nonuniform channel and the uniform channel is nearly linear with the quality.

Effects of Wall Sub-Cooling on Local Heat Transfer for Forced Convection Condensation of Steam/air in A Horizontal Tube

Xu Huiqiang, Sun Qiunan, Gu Haifeng, Li Hao, Sun Zhongning

2016, 37(1): 43-47. doi: 10.13832/j.jnpe.2016.01.0043

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For the purpose of analyzing the effects of wall sub-cooling on the heat transfer characteristics of forced convection condensation for steam/air mixtures in a horizontal tube, the experiments under air-cooling and water-cooling have been conducted. By comparing the experimental data for different inlet air mass fractions, mixtures velocities and coolant volume flow rates, the variation of local heat transfer coefficient with wall sub-cooling was obtained. The results show that for annular and wavy flow, the condensation heat transfer coefficient increases with wall sub-cooling while decreases with wall sub-cooling for stratified flow. The positive effects of the increasing wall sub-cooling on the condensation heat transfer coefficient is enhanced with the rise of inlet air mass fraction and mixture gases velocity for annular and wavy flow.

Fatigue Behavior of TA16 Tube with Surface Defect under High Cycle Loading

He Kun, Zhao Yuxiang, Dang Ying, Wang Li, Jiang Fan

2016, 37(1): 48-51. doi: 10.13832/j.jnpe.2016.01.0048

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The high cycle fatigue behavior of TA16 alloy tube with the internal surface defect was evaluated. The defect of TA16 tube was examined by the method of ultrasonic flaw detection. Two kinds of TA16 tube were prepared: the traditional preparation technology has the crack-like and jagged defects, and the improved one has the shallow and wide defects. The high cycle fatigue was preformed under axial loading. The fatigue life of traditional tubes are between 1×10⁵ and 6×10⁵ cycles under the ultrasonic flaw detection from 25% to 90%. The life of improved ones is all above 10⁶ cycles. There is no fatigue crack source in the fracture surface. The crack propagation direction is from the inner surface of tube to the outside, which means that states of materials surface have some influence on the fatigue life.

Coupled Numerical Simulation of Nuclear Fuel Particles Fluidization and CVD Reaction in Deposition Chamber for Niobium Coating

Li Tongye, Wang Hui, Chen Jianhua, Pan Xiaoqiang

2016, 37(1): 52-56. doi: 10.13832/j.jnpe.2016.01.0052

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In order to study the agglomeration mechanism, the gas-solid flow field in the deposition chamber was numerically studied by Euler-Euler method, and the steady-state reduction reaction products were simulated by HSC Chemistry. Combined the flow field distribution and reduction reaction simulation, the velocity and component concentration fields in the deposition chamber were obtained. The results showed that both the gas-solid flow fields and reaction products concentration fields in the deposition chamber were not uniform, and local particle accumulation phenomenon in deposition chamber cone section was found. The bed agglomeration can be attributed to the melting of the low valence niobium chloride produced by reduction reaction. The reaction rate and NbCl₅ flow non-uniformity can lead to the low valence niobium chloride generation increases significantly, which can promote the bed agglomeration.

Microstructure and Tensile Properties of 304L Austenitic Stainless Joints Produced by Friction Stir Welding and Tungsten Inert-Gas Welding

Xu Jiangming, Xu Chunrong, Fan Baoquan, Wang Shizhong

2016, 37(1): 57-61. doi: 10.13832/j.jnpe.2015.06.0057

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3 mm thick 304 L austenitic stainless steel plates were welded by Friction Stir Welding（FSW） and Tungsten Inert-Gas Welding（TIG） respectively, then the microstructure and tensile properties of the welding joints of the two different types of welding were compared and analyzed. The results of the comparison and the analysis show that the FSW welding joint microstructures is composed of four regions, welded nugget zone, thermal-mechanically affected zone（TMAZ）, heat affected zone（HAZ）, and shoulder affected zone（SAZ）. And the microstructure in the nugget is uniform fine-scale equiaxed recrystallisation grain, and the materials in TMAZ underwent plastic deformation, but the materials in HAZ just underwent heat effect. The TIG nugget includes cellular dendrite austenitic, lath ferrite or vermicular ferrite. The tensile properties of FSW joints is the same as those of the TIG joints, and both of the tensile properties of the two types of welding joints are slightly higher than those of the base materials of the welding joints.

Study on Automatic Control Method for Clod Start-up of Nuclear Power Plant

Yu Ren, Chen Zhi, Yang Huailei, Chen Yusheng, Xiao Kai, Liu Yang

2016, 37(1): 62-66. doi: 10.13832/j.jnpe.2016.01.0062

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The overall control tactics for the automatic clod start-up of nuclear power plant is discussed in the paper. Then, different control methods are designed to realize the auto-control of the primary loop coolant temperature, the levels of the temperature, the pressure and the water of the pressurizer, and the steam pressure of SG, respectively, in different phases. The control effects are demonstrated using a comprehensive nuclear power plant control simulation platform based on the RELAP5 and SIMULINK. The simulation results show that with the designed control methods, the automatic control of the nuclear power plant start-up from cold shutdown can be realized, and the requirements of operating regulations and safety can be satisfied.

Study on Reasonability of Accident Conditions Load Combination for Nuclear Power Plant Primary Piping

Ai Honglei, Xie Hai, He Feng, Wang Xinjun, Lu Xifeng

2016, 37(1): 67-71. doi: 10.13832/j.jnpe.2016.01.0067

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For verifying the reasonability of combination of SSE and LOCA which affect the nuclear power plant primary piping during accident conditions, the simultaneous SSE/LOCA effect on primary piping should be demonstrated that can not occur. Concluding from probability statistical analysis, the probability of the simultaneous SSE/LOCA event is lower than that considered in the nuclear power plant design if the events are considered to be independent. According to deterministic methodology calculation, SSE is not the initiator of a LOCA even there is a detectable leakage flaw in the primary piping. Consequently, the assumption of that the SSE and LOCA can not act simultaneous is reasonable in the primary piping design, the load combination of SSE and LOCA which is combined as the square root of sum of square method is conservative in the primary piping stress analysis, and that can assure the protection of the health and safety of the public.

Study on Critical Current of Movable Gripper Coil in CRDM Based on a Simplified Simulation Mechanism

Duan Yuangang, Qiang Wenjiang, Lan Yinhui, Huang Yili, Liu Feihua

2016, 37(1): 72-76. doi: 10.13832/j.jnpe.2016.01.0072

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Based on the mechanical and magnetic structure near the movable gripper coil of magnetic type control rod drive mechanism, a simplified simulation mechanism with size ratio of 1:2 was set up. Based on this system, motion characteristics of the movable armature were studied. Both the magnetic circuit calculation and ANSYS finite element method were used to theoretically analyze the factors on critical current of movable gripper coil in lifting and releasing process. The results compared with theoretical analysis and experimental test showed that ANSYS FEM results had better coherence with the measured values. ANSYS FEM results showed that the releasing current increased with reducing the permeability of the non-magnetic shim and increasing the thickness of the non-magnetic shim. Other factors including permeability of ferromagnetic materials, lifting load and the lifting gap also had a significant influence upon the critical lifting current and/or the critical releasing current.

Research on the Dynamic Compensation Algorithm of Vanadium Self-Powered Neutron Detector Based on Robust Filtering Theory

Peng Xingjie, Zhang Zhizhu, Li Qing, Wang Kan

2016, 37(1): 77-81. doi: 10.13832/j.jnpe.2016.01.0077

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Vanadium self-powered neutron detector（SPND） signal can be used to reconstruct core three-dimensional power distribution. Due to the delayed detector current response to flux variation, the dynamic compensation of the vanadium self-powered neutron detector current is needed to ensure the veracity of the neutron flux measurement. This research is focused on SPND dynamic compensation algorithm based on robust filter theory, and the filter design problems are solved via the convex optimization framework using linear matrix inequalities. The numerical simulation results show that three filter based on robust filtering theory all can provide a reasonable balance between response speed and noise suppression.

Development of Off-Line Leak Detection Device for Micro-Rupture Fuel Assemblies

Jia Yaqing, Li Chengye, Li Jinsong, Zhang Jinsong, Cheng Ying

2016, 37(1): 82-85. doi: 10.13832/j.jnpe.2016.01.0082

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To solve the offline leak detection problem for the irradiated low burnup fuel assembly and micro-rupture which can not bedewatered, the research on technology of fuel assembly leak detection, pumping gas technology research and process checking research are carried out in this paper. Low temperature adsorption method and gas pumping and adsorption method are applied to solve the problem of radioactive gas detection in water. Based on the results of above research, we have developed leak detection device which has been validated by experiment. The detection limit of the leakage detecting device for ¹³⁷ Cs and ⁸⁵ Kr are 0.5Bq/L and 19Bq/L.

Study on Leak Detection for Passive Residual Heat Remove System

Wang Yu, Chen Zhihui, Hao Chengming, Sun Yan, Huang Wei

2016, 37(1): 86-90. doi: 10.13832/j.jnpe.2016.01.0086

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Heat transfer model of inlet tube is established for Small PWR（ACP100） passive residual heat removal system. The heat transfer mechanism for the leakage of inlet line and passive residual system is researched. The results show that the temperature instrument located more than 0.3 m below the inlet line high point is evaluated sufficient to avoid the effect of the source. It is effective to detect and quantify the leaks by temperature monitor. Increasing the leak rate, the maximum temperature measured by the instrument tends to increase. For the leakage above 8×10^-4m³/h, the effect of axial heat flux can be disregarded without affecting significantly the calculation.

Application of Reliability and Technique Centered Maintenance（RtCM) Method in Moisture Separator Reheater System of A Nuclear Power Plant

Cheng Bin, Zhang Guanghui

2016, 37(1): 91-94. doi: 10.13832/j.jnpe.2016.01.0091

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Reliability and technique centered maintenance（RtCM） is a systematic engineering method used to determine the preventive maintenance requirement of equipment assets and optimizing the maintenance system. This paper has introduced the process and technological innovation of RtCM method through a practical example of RtCM application in the moisture separator reheater system in a nuclear power plant. Besides, the economic benefit resulting from RtCM application was evaluated. The results indicate that RtCM method, into which the maintenance templates, technical characteristic analysis, equipment identification and quantitative analysis technique were introduced, is a more efficient and more advanced method in the maintenance the optimization field and plays an important role in improving the equipment reliability.

Analysis of Root Cause for Safety Valve Leak

Kang Pengcheng, Hu Jun

2016, 37(1): 95-98. doi: 10.13832/j.jnpe.2016.01.0095

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The special research is carried out on the leakage problem of the safety valve used in the field test. The main failure cause of safety valve has been found by dismantled them into parts, by checking the surfaces and the major dimensions, and analysis and inspection of the initial reason, measuring the coaxiality, then comparative tests for the relief valve, changing the parts, testing of airproof performance at cold state and hot state. According to this, the corresponding improvements has been taken to the 4 safety valve for repairing. The main cause of the problems that obtained and the improvements is accurate and appropriate from the testing results of the equipment and the submarine. According to the checkouts and tests results of products that hand over recently, the quality and the reliability of the safety valve has been improved evidently.

Analysis of Reactor Lower Core Support Plate Heat Treatment Distortion and Repair

Chen Miaoxin, Wu Zhiyuan

2016, 37(1): 99-102. doi: 10.13832/j.jnpe.2016.01.0099

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The flatness of the lower core support plate and the position of the fuel alignment pin holes were found deviated from the design requirements due to the heat treatment distortion during the manufacturing of the reactor vessel internals for the Haiyang Nuclear Power Plant Unit 1. The designer provided the treatment proposal and the repair plans after the cause analysis. This paper focuses on the deviations of the lower core support plate for Unit 1and describes the causes of the deviations. The repair plans and repair progress are also presented in this paper.

Fault Detection Design for Reactor Protection System of Hainan Changjiang Nuclear Power Station

Luo Wei, Feng Wei, Liu Hongchun, Wang Yinli, Xu Dongfang

2016, 37(1): 103-108. doi: 10.13832/j.jnpe.2016.01.0103

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Reactor protection system is a key part of instrument and control system in nuclear power plants. In order to detect the fault of the protection system equipment, validate the availability and assure the nuclear power plant safety, the periodic fault detection shall be applied. This paper introduces the fault detection design, scope and function of the reactor protection system in Hainan Changjiang nuclear power plant based on Tricon V10 programmable logic controller（PLC）, and also analyzes the characteristics of fault detection.

Study on Effects of Temperature-Power Curve on MSHIM Strategy

Wang Jinyu, Wang Chuang, Liu Tongxian

2016, 37(1): 109-112. doi: 10.13832/j.jnpe.2016.01.0109

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This paper takes Qinshan phase II NPP（600 MW） as the research target, and applies different reactor temperature-power curves on the reactor, then studies the effects of different reactor temperature-power curves on MSHIM. The analysis indicates that through the optimization of the reactor temperature-power curve, the motion range of control rod could be reduced, and the load-follow of broader scope would be possible.

Motion Simulation for Delivery Process of In-Service Inspection Equipment

Zhu Xingli, Tian Ting, Zhou Lifeng, Chen Shu

2016, 37(1): 113-116. doi: 10.13832/j.jnpe.2016.01.0113

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AP1000 passive PWR steam generator and main pump is connected by welding, and these welds require in-service inspection. This paper focus on the 3D motion simulation route and its movement algorithm for inspection equipment, based on Open Inventor 3D engine. The developed 3D simulation system realizes the real-time simulation monitoring for the inspection equipment delivery process and working environment, and it has the important practical significance for promoting the intuitive of inspection equipment delivery process and improving the safety of inspection activities.

Experimental Study on Bubble Velocity Characteristics in Water under Sway Motion

Wen Jing, Tan Sichao, Fu Xuekuan, Meng tao, Song Yulin

2016, 37(1): 117-122. doi: 10.13832/j.jnpe.2016.01.0117

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Experimental study of bubble velocity characteristics under sway motion is carried out. An experimental system is designed and manufactured. A fast camera is used to record the behavior of the bubbles. By tracking the path of the bubbles, movement parameters of the bubble are obtained under different motion conditions. It is found that the horizontal velocity, vertical velocity and path of bubbles are all obviously influenced by the inertial force and sloshing of free surface which are both induced by sway motion. The longer the sway motion period is, the greater the peak horizontal velocity is, and the sharper the path is and the shorter the vertical velocity is. Compared with inertial force, sloshing of free surface has a greater impact on the horizontal velocity.

Preliminary 3D Numerical Study on Flow Blockage Accident in Multi-layer Annular Flow Channels

Fan Wenyuan, Guo Yun, Peng Changhong

2016, 37(1): 123-128. doi: 10.13832/j.jnpe.2016.01.0123

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The multi-layer annular fuel assembly, which is consisted of annular-type fuel plates, is easily blocked. It is necessary to study the flow and heat transfer behavior of the assembly under flow blockage condition. In this study, basic problems in three-dimensional investigation on flow blockage accident in multi-layer annular channels are discussed. Scalable wall functions are proved to be suitable to simulate flow-rate-decaying cases. A 90% inlet flow blockage case is then calculated using velocity-inlet and pressure-inlet respectively, and the pressure-inlet is proved to be the proper boundary condition for CFD simulations on flow blockages. Both transient and steady simulations are done, and flow and heat transfer redistributions caused by the blockage are analyzed.

Numerical Research for Passive Residual Heat Removal Heat Exchanger under Natural Convection Condition

Ge Jian, Cong Tenglong, Zhang Wenwen, Tian Wenxi, Qiu Suizheng, Su Guanghui

2016, 37(1): 129-132. doi: 10.13832/j.jnpe.2016.01.0129

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Computational fluid dynamics（CFD） methodology is adopted to simulate the fluid flow and heat transfer characteristics of the passive residual heat removal heat exchanger（PRHRHX）. The C-type tube region is modeled by the porous media method. The coupled heat transfer rate from the primary side fluid to the secondary side fluid of the PRHRHX tube is calculated during the calculation. The secondary side temperature and velocity distribution in the in-containment refueling water storage tank（IRWST） at different times are analyzed. The primary side fluid temperature distribution inside the heat transfer tube is obtained.

Development and Application of a Sub-Channel Analysis Code in Ocean Environment

Xiang Xiong, Shan Jianqiang, Zhang Bo

2016, 37(1): 133-138. doi: 10.13832/j.jnpe.2016.01.0133

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Based on the definition of the ocean environment, the calculation methods of additional force in heaving and rolling motion are analyzed, and the modified methods of momentum equations and boundary conditions are obtained. Based on these, the sub-channel code ATHAS, which is with self-owned intellectual property, is modified and a sub-channel code named ATHAS/OE is obtained, which can be applied to the ocean environment. Thermal-hydraulics analysis of MUTSU reactor in heaving and rolling motion is carried using ATHAS/OE. The results indicate that in heaving motion, the calculation results of ATHAS/OE and the modified COBRA-IV match well. The outlet mass flux and quality of sub-channels and MDNBR of reactor are oscillated periodically. Because of the modification of Critical heat flux（CHF）calculation method in heaving motion, the MDNBR of reactor in heaving motion always decreases compared with that in land-based condition. The MDNBR of reactor is oscillated slightly because of no modification of CHF calculation in rolling motion.

Accelerating Domain-Decomposed Parallel Matrix MOC with Multi-Domain Coupled PGMRES Algorithm

Wu Wenbin, Li Qing, Wang Kan

2016, 37(1): 139-142. doi: 10.13832/j.jnpe.2016.01.0139

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In this paper, spacial domain-decomposed parallel Matrix MOC and relevant multi-domain coupled PGMRES accelerating algorithm were studied. In this algorithm, PGMRES from PETSc library was adopted to solve the angular flux of inner boundaries directly, thus improving the convergence rate. Numerical results demonstrated that the multi-domain coupled PGMRES algorithm keeps good accuracy and obtains great speed ratio.

Evaluation of Nuclear Safety-Critical Software Reliability of DCS

Liu Ying, Yang Ming

2016, 37(1): 143-147. doi: 10.13832/j.jnpe.2016.01.0143

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This paper tries to choose Bayesian Belief Networks（BBN） method to build the evaluation models. The stage evaluation models are constructed based on NUREG-0800 BTP7-14. It finished the software real-time evaluation in stages using 13 first-level indexes, 74 second-level indexes, 326 third-level indexes.HUGIN software is chosen as the Bayesian Networks Analysis tool. Predictive inference and sensitivity analysis are given to the testing object. After testing, the degree of compliance with standards at different stages of the life cycle can be obtained. The software reliability is 98.84% by using the evaluation model, thus, the reliability of the failure-free software operation can be calculated from the quantitative aspect. After predictive inference, sensitivity analysis, the weaknesses in software development process can be found from the qualitative aspect. It can be a base for evaluating the reliability and safety of the DCS.

In-pile Application and Preliminary Performance Analysis of Silicon Carbide Composite Cladding

Li Wenjie, Gao Shixin, Chen Ping, Jiao Yongjun, Chen Bingde

2016, 37(1): 148-151. doi: 10.13832/j.jnpe.2016.01.0148

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Silicon carbide composite cladding used as the fuel cladding material can improve many performances for a PWR. In order to evaluate the in-pile performance of silicon carbide composite cladding, fuel behavior models of FUPAC were modified. A preliminary analysis was also performed, and the results showed that the core design safety criteria can be satisfied.

Research on Impact Properties of Auxiliary Bearings in HTR-10 AMB Helium Circulator Based on Quasi-Static Method

Yang Lei, Yang Guojun, Shi Zhengang

2016, 37(1): 152-156. doi: 10.13832/j.jnpe.2016.01.0132

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The AMB’s impact properties are studied in this paper based on AMB in the helium circulator for the 10 MW high temperature gas cooled reactor（HTR-10）. The impact force when the vertical rotor drops is calculated, and the amount of deformation of the auxiliary bearings is calculated based on the quasi static analysis. The calculation results show that the acting force between the rotor and the auxiliary bearing is roughly the same, no matter what is the rotational speed of the rotor. And after a certain time, the acting force reaches a constant value which is only concerned with the rotor（the rotor speed, quality, and etc）. The deformation amount of the auxiliary bearing is also roughly the same according to the results. The deformation amount appears as the bearing’s vibration displacement on the macro level. So it can measure the state of the auxiliary bearing.

Study on Resin Type Selection in Liquid Radwaste System of CAP Nuclear Power Plant

Liu Jiean, Liu Dan, Wang Xin, Chen Bin, Weng Minghui

2016, 37(1): 157-161. doi: 10.13832/j.jnpe.2016.01.0157

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Two types of gel cation resins with different cross-linking degrees（16% and 8%） are studied for the nuclear grade resin type selection in CAP（China Advanced Pressurized Water Reactor） series of Generation III nuclear power plants. The effect of different resin specifications on operation performance is evaluated by means of dynamic simulated experiments. Results show that the monosphere resin with higher cross-linking degree（e.g. 16%） has an advantage in respect of decontamination, operation life span, differential pressure and economical efficiency. So resin of high cross-linking degree is recommended for the ion exchange design in the liquid radwaste system of CAP series plants.

International R&D Activities of SCWR and Illumination

Zhou Zhiru, Huang Yanping, Zang Jinguang, Li Yongliang, Xiao Zejun

2016, 37(1): 162-166. doi: 10.13832/j.jnpe.2016.01.0162

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Based on the nuclear strategies and technical plans, Japan, Europe, Canada, Russia, China and other countries are devoted to the R&D of the supercritical water cooled reactor（SCWR） technology and have achieved lots of progress. This paper summarizes the international activities of SCWR from the view of the system development, discusses the outline of the participation of China in GIF-SCWR and its future plan, and provides some constructive suggestions for further development of SCWR R&D in China.

2016 Vol. 37, No. 1