Trends in computational intelligence in nuclear engineering

Several changes to the focus of Computational Intelligence in Nuclear Engineering have occurred in the past few years. With earlier activities focusing on the development of condition monitoring and diagnostic techniques for current nuclear power plants, recent activities have focused on the implementation of those methods and the development of methods for next generation plants and space reactors. These advanced techniques are expected to become increasingly important as current generation nuclear power plants have their licenses extended to 60 years and next generation reactors are being designed to operate for extended fuel cycles (up to 25 years), with less operator oversight, and especially for nuclear plants operating in severe environments such as space or ice-bound locations.     

Simulation of nuclear reactor dynamics equations using reconfigurable computing

This paper describes the application of a multilayer discrete-time cellular neural network (DT-CNN¹) and its hardware implementation on a field programmable gate array (FPGA²) to model and simulate the nuclear reactor dynamics equations. A new computing architecture model based on FPGA and its detailed hardware implementation are proposed for accelerating the solution of nuclear reactor dynamics equations. The proposed FPGA-based reconfigurable computing platform is implemented on a Xilinx FPGA device and is utilized to simulate step and ramp perturbation transients in typical 2D nuclear reactor cores. Properties of the implemented specialized architecture are examined in terms of speed and accuracy against the numerical solution of the nuclear reactor dynamics equations using MATLAB and C programs. Steady state as well as transient simulations, show a very good comparison between the two methods. Also, the validity of the synthesized architecture as a hardware accelerator is demonstrated.     

Alexisismon isolation engineering for nuclear power plants

This paper reviews the special requirements regarding efficiency, licensibility (reliability) and cost which should be met to achieve an optimum base isolated nuclear power plant design. It then describes the Alexisismon-2, patented isolation system developed by the author, underlines its original properties (linearity and separation of functions) and presents a conceptual design of its application to a nuclear power plant. The great reliability of the system components is demonstrated. The efficiency of the A-2 is found to be very high: a reduction factor of the base shear induced in the plant higher than 25 is achieved for all examined real accelerograms scaled to 1 g GPA. So the isolation components, the structural system of the plant, its equipment and systems can be easily designed to remain in the elastic range of stresses and strain even for seismic input with GPA higher than 2 g.     

多项目核电工程管理创新

介绍了我国核电的发展形势,通过借鉴国外核电工程管理模式,提出变革传统的直线职能式管理,提升组织适应性;完善项目团队运作管理,保持机制灵活性;搭建多项目管理平台,实现运作精细化等管理创新。     

Practical reliability engineering applications to nuclear safety

PRA studies have been successful in providing a quantitative perspective on the important contributions to risk and on the relative impact of potential hardware modifications and procedural changes in reducing public risk. In addition it is the expectation that regulatory agencies will also use this technology to justify a relaxation in requirements that are too strict and the elimination of requirements that are irrelevant or counter to safety. This paper outlines several on-going application oriented R&D efforts that will improve safety in operation, lead to a continuing demonstration that nuclear plants are achieving acceptably low risk, and achieve a higher plant productivity.     

The interuniversity program for safer nuclear power engineering

Moscow Engineering-Physics Institute. Translated from Atomnaya Énergiya, Vol. 73, No. 6, pp. 419-420, December, 1992.     

Development of nuclear power plant real-time engineering simulator

A nuclear power plant real-time engineering simulator was developed based on general-purpose thermal-hydraulic system simulation code RELAPS. It mainly consists of three parts: improved thermal-hydraulic system simulation code RELAP5, control and protection system and human-machine interface. A normal transient of CHASHMA nuclear power plant turbine step load change from 100% to 90% of full power, was simulated by the engineering simulator as an application example. This paper presents structure and main features of the engineering simulator, and application results are shown and discussed.     

INPRO economic assessment of the IRIS nuclear reactor for deployment in Brazil

This paper presents the results of the economic assessment of the International Reactor Innovative and Secure (IRIS) for deployment in Brazil using the assessment methodology developed under the International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO), co-ordinated by the International Atomic Energy Agency (IAEA). INPRO initiated in 2001 and has the main objective of helping to ensure that nuclear energy will be available to contribute in a sustainable manner to the energy needs of the 21st century. Among its missions is the development of a methodology to assess innovative nuclear energy systems (INSs) on a global, regional and national basis. In 2005, Brazil submitted a proposal for the assessment of two small-size reactors as components of an INS, completed with a conventional open nuclear fuel cycle based on enriched uranium. One of the reactors assessed was IRIS, a small-size, modular, integral-type PWR reactor. IRIS was evaluated with regard to the areas of reactor safety and economics only. This paper outlines the rationale for the study and summarizes the results of the economic assessment. The study concluded that the reference design of IRIS complies with most of INPRO economics criteria and has potential to comply with the remaining ones.     

Recent developments in data mining and soft computing for JET with a view on ITER

In order to handle the vast amount of information collected by JET diagnostics, which can exceed 10 Gbytes of data per shot, a series of new soft computing methods are being developed. They cover various aspects of the data analysis process, ranging from information retrieval to statistical confidence and machine learning. In this paper some recent developments are described. History effects in the plasma evolution leading to disruptions have been investigated with the use of Artificial Neural Networks. New image processing algorithms, based on optical flow techniques, are being used to derive quantitative information about the movement of objects like filaments at the edge of JET plasmas. Adaptive filters, mainly of the Kalman type, have been successfully implemented for the online filtering of MSE data for real time purposes.     

A method of computing stress range and fatigue damage in a nuclear piping system

The ASME Boiler and Pressure Vessel Code, Section III (1971) employs stress range and fatigue evaluation as part of the total stress evaluation of piping systems. One method of computing this stress range and the resultant fatigue damage using the basic equations of the Code is presented here. This method is then illustrated by examples and discussed in detail.     

核与辐射恐怖袭击事件源项估算

核与辐射恐怖袭击事件一旦发生,如果对释放到环境中放射性核素的种类和数量等信息不清楚,将很难对其所造成的后果做出较为合理的评价,对应急决策指挥和防护行动的实施造成一定困难.叙述了核与辐射恐怖袭击事件后果的严重性,指出核与辐射恐怖袭击的放射性危害以长寿命α气溶胶为主,化学危害以极毒的放射性核素为主.建立了一种源项分析方法,利用该方法对一模拟的放射性分散装置模型爆炸后的源项进行了估算,给出了释放核素的类型和释放量.     

Principles for engineering active-passive hydrodynamic control-and-safety systems for nuclear reactors

The principles for developing active-passive hydrodynamic systems for nuclear reactors are presented. The determination of the parameters of hydrodynamic control systems is examined: static characteristic, nonstationary motion (acceleration), and signaling of the state of a working organ. Recommendations are made concerning the calculation of the hydrodynamic control systems. Their use in the process of investigation, design, adjustment, and operation makes it is possible to determine the parameters and characteristics quickly by using simple means on the object. Familiarization with the particularities of the development of hydraulic control systems will aid in wider adoption of such systems in building nuclear reactors. Translated from Atomnaya énergiya, Vol. 106, No. 3, pp. 140–148, March, 2009.     

核工程建造过程中不符合项的纠正管理

在核工程建造过程中,不符合项的有效纠正是质量管理的一项重要工作。本文介绍了3号换热器R55C45换热管采取堵管措施、22块新蓄电池更换已失效的旧蓄电池、密封筒划伤后的处理和中间水池底板混凝土裂缝加固共4项不符合项纠正管理的成功经验,可为正在建造的核工程提供了有益借鉴。     

Grain boundary engineering of austenitic steel PNC316 for use in nuclear reactors

Austenitic stainless steel PNC316 was subjected to grain boundary engineering (GBE). It was found that the grain boundary engineered PNC316 (PNC316-GBEM) had a coincidence site lattice (CSL) fraction of 86% and that the network of random grain boundaries was perfectly divided by the CSL boundaries. The thermal stability and the void swelling behavior of PNC316-GBEM were investigated by means of SEM and TEM analyses. After thermal aging at 973 K for 100 h, structural changes were observed neither in the grain boundary networks of PNC316-GBEM nor in another sample of PNC316-GBEM subjected to 20% additional cold rolling, PNC316-GBEM20%CW. PNC316-GBEM showed a higher void swelling rate than as-received PNC316 (PNC316-AS). However, with additional 20% cold rolling after GBE, the void swelling rate decreased to as low as that of PNC316-AS.     

核电工程管理程序评估创新与实践

介绍了山东核电有限公司在AP1000核电工程程序管理工作中创新采用的程序评估方法具体的实施方式和过程,总结了程序评估实施的效果,分析了程序评估这一管理方法具有的优势和存在的不足。