水生生物辐射影响评价软件ERICA版本变化分析及工程应用

介绍了水生生物辐射影响评价软件ERICA程序的计算原理及评价准则,分析了程序新版本ERICA1.2与上一版本ERICA1.0相比的主要变化,并以我国某压水堆核电厂厂址为例,分别采用程序ERICA 1.0版和1.2版分析该电厂正常运行工况下液态流出物排放对厂址附近水生生物的辐射影响。结果表明,使用程序的两个版本计算该电厂两台机组正常运行时的液态流出物对厂址附近水生生物的影响都是可接受的,厂址附近水生生物是安全的。     

火力发电机组节能分析模型及研究

节能分析是火电企业开展节能减排活动的基础工作。在火电机组煤耗计算模型的基础上,建立了火电机组能耗计算模型和单因素敏感性分析模型,分析和计算在不同负荷下,锅炉效率、热耗率和厂用电率变化对供电煤耗率的影响程度。根据某600MW机组设计参数,计算了机组在不同运行工况下的经济性指标和能耗指标敏感因子,得到了机组在不同运行工况下的节能潜力及效果,对火电企业节能减排工作的开展具有一定的指导意义。     

汽轮机阀门高温蠕变计算有限元单元类型选择

长期高温下的蠕变失效是金属材料典型的高温强度问题,随着汽轮机主蒸汽参数的不断提高,主汽门高温蠕变强度的精确计算考核尤为重要。以ABAQUS有限元软件为工具,采用不同的常用单元类型对某高参数汽轮机主蒸汽阀门高温蠕变进行计算,通过分析对比计算结果得出:在网格质量都有保证并且边界条件相同的前提下,不同单元类型的计算结果有较大差异,单元类型的选择直接影响计算结果。     

某核电厂回填场地土层地震反应分析

采用工程类比法,获取回填土石料的动力参数。运用SHAKE91计算程序,计算了回填场地土层的地震反应。计算结果表明,经土层的放大作用后地表反应谱加速度幅值较厂址基岩面的反应谱加速度幅值增大明显。文章可为一般回填场地土层地震反应分析提供参考。     

城市道路中机动车尾气排放分析

机动车的排气污染对人体的危害是巨大的,在城市空气污染中机动车的排气污染占很大的份额.随着国家经济的高速发展,机动车的数量也正飞速增长,机动车排气污染问题已相当严重.为了对机动车在城市道路上排放的实际情况有一定了解,文中给出了城市道路中不同类型的机动车车流量的实测值.并选取不同的排放因子对实测结果进行处理分析,计算得出不同类型的机动车在道路上的实时排放量.这将对城市的空气污染治理提供一定的参考.     

城市道路中机动车尾气排放分析

机动车的排气污染对人体的危害是巨大的，在城市空气污染中机动车的排气污染占很大的份额。随着国家经济的高速发展，机动车的数量也正飞速半长，机动车排气污染问题己相当严重。为了对机动车在城市道路上排放的实际情况有一定了解，文中给出了城市道路中不同类型的机动车车流量的实测值。并选取不同的排放因子对实测结果进行处理分析，计算得出不同类型的机动车在道路上的实时排放量。这将对城市的空气污染治理提供一定的参考。     

基于湍流分布特征系数的消声器压力损失模型

进行了消声单元压力损失流场数值计算,通过试验验证了计算方法的准确性.对比了不同边界条件下的湍动能分布特征,提出了湍流分布特征系数,建立了关于湍动能、密度和湍流分布特征系数的消声器压力损失模型,通过不同类型消声单元和不同气流进口速度验证了模型,以穿孔管消声单元为例建立了压力损失模型,并讨论了主要结构参数对压力损失的影响.结果表明:对不同结构参数消声单元压力损失模型计算的相对误差不超过8%,,不同气流速度下模型计算相对误差不超过7%,;穿孔管消声单元压力损失随穿孔率、穿孔部分长度的增大而减低,随腔体直径的增大而增加,穿孔直径则对压力损失几乎没影响.     

锅炉各受热面吹灰作用的对比研究

为优化运行性能，通过清洁因子变化对锅炉主要运行参数影响的性能计算，得到了锅炉不同部位受热面的吹灰作用种类和大小，可作为现场指导吹灰优化运行的依据。不同部位受热面的吹灰作用因受热面位置、受热面种类和大小的不同而异，其重要性也不同。位于烟气流程起始点和蒸汽流程终点的受热面是吹灰优化运行的重点。图13表3参3     

太阳能热电站厂址选择影响因素分析

与常规燃煤电站和太阳能光伏电站不同,太阳能热电站厂址选择是一项受到各方面因素影响的综合性耦合性的工作。本文依据太阳能热发电技术自身特点,提取了资源性、自然性、市场性及环保性4个条件,分别详细论述分析影响太阳能热电站厂址选择的因素,从而形成完整的太阳能热发电电站厂址选择的影响因素体系,并分析厂址选择的方法。     

异步风力发电系统的特征根灵敏度分析

文章以异步风力发电机组的动态模型为基础,在Matlab/Simulink中进行仿真和量测,得到相关稳态运行数据。通过参与因子的计算,分析了不同振荡模态与系统的动态过程之间的对应关系,通过特征根灵敏度的计算,得到了不同系统物理参数对相应振荡模态的影响,得到的分析结果与参与因子的分析结果是一致的,这些分析结果对进一步提高并网的异步风力发电机组的动态稳定性具有一定的参考价值。     

Calpuff模式在核电厂事故对水体影响分析中的应用

利用某厂址全年逐时的气象观测数据,通过Calpuff模式模拟计算了不同事故工况下核电厂放射性流出物对周边水资源可能造成的污染情况。计算表明:利用真实的风向、降水等气象条件模拟计算结果更加合理,选址假想事故和IC释放类工况造成的水库沉积核素浓度远低于GB 18871-2002规定的食品通用行动水平。尽管采用了更真实的气象条件,BP释放类造成的核素沉积浓度仍高于国标中规定的食品通用行动水平,因此在设计上应避免此类严重事故的发生。     

美国核电厂抗震主系统分析要求的近期变化

近期美国核管会NRC颁布的标准审查大纲《Standard Review Plan》Rev.3(2007)版已通过我国核安全审评中心翻译出版,表明我国核安全局将按最严的国际标准执行核工程的安全审查。通过对比美国核管会标准审查大纲SRP 3.7.2节1989版、2007版以及最新2013版的抗震主系统主要内容,结合以往核电工程抗震分析的实践经验,按其所列验收准则各条分别作出专业性的讲解与点评。研究表明:SRP 2013版在概念上更清晰,并在可操作性上更加完善,研究成果对理解核电厂抗震主系统分析要求具有很好的参考价值。     

Detached Eddy Simulation of hydrogen turbulent dispersion in nuclear containment compartment using GASFLOW-MPI

During the severe accident in nuclear power plants (NPPs), hydrogen is generated due to the zirconium-water reaction and released from the breaks in coolant pipe forming a locally high concentration hydrogen cloud in the steam generator (SG) compartment, which plays a key role for hydrogen safety analysis in NPPs. Accurate prediction of the turbulent dispersion process of hydrogen-steam gas mixture is a critical topic for a successful simulation of the flammable cloud distribution in SG compartment. In this study, the high-fidelity temporal evolution of the hydrogen turbulent dispersion in a SG compartment is performed using the Detached Eddy Simulation (DES) based on the parallel CFD code GASFLOW-MPI to capture more detailed unsteady turbulent information. Firstly, the newly developed DES turbulence model is validated using two turbulent benchmarks, a backward-facing step turbulent flow and a hydrogen turbulent jet. The simulation results are consistent well with the experimental data. Then a SG compartment model including one steam generator, two coolant pumps, a hot leg and two cold legs is built using the specialized auto-mesh generation module. There are two modes of turbulent dispersion behavior due to the turbulent driven force in the containment, i.e. jet dominated by initial monument and plume dominated by buoyancy. The simulation result shows that the decay rate for centerline velocity obeys $1/z$ law as well as hydrogen volume fraction, indicating a turbulent jet during the steam dominated phase. There is also a relatively long potential core region which could impinge on the bottom concrete floor for the downwards jet. While the hydrogen release transfers from a turbulent jet to a turbulent plume outside the region near the inlet during the hydrogen dominated phase. Different from the turbulent jet, the centerline velocity at the plume region decays with the slope $1/z^{1/3}$, and the decay rate for the centerline hydrogen volume fraction is $1/z^{5/3}$ during this phase. Compared with the jet flow, the potential core region of the plume flow is relatively short, forming a hydrogen cloud near the inlet. The combustibility evaluation shows that the combustion clouds can be generated in the source compartment at the hydrogen dominated phase. However, they will be diluted by the following persistent steam injection from the break. This can provide technical support for the design of hydrogen mitigation system.     

第十一届中国核电技术发展高峰论坛会议综述

为促进核电产业安全高效发展,加快落实中国核电“走出去”战略,由上海市核电办公室和中国能源建设集团广东省电力设计研究院有限公司(简称中国能建广东院)联合主办、中国核能行业协会和中国核工业勘测设计协会协办,诺本集团承办的第十一届中国核电技术发展高峰论坛于2016年8月26日在中国能建广东院召开。本次论坛高屋建瓴地探讨了我国核电发展的实践与展望,强调了加强安全监管对助力核电发展的重要性,探索了加强协同创新和技术创新对推动核电产业实现新突破的重要作用,介绍了我国在建的多种堆型核电厂的最新技术特点及工程建设的进展情况,包括具有自主知识产权的三代技术“华龙一号”、我国先进快堆技术、国家科技重大专项高温气冷堆示范工程等,同时就核电装备智能制造应用及通过技术创新提高电站的经济效率等进行了深入地探讨,本次论坛对推动中国核电技术的发展具有重要的意义。     

Advanced Control Room Design

Control rooms are a key aspect of the safety and efficiency of nuclear power plants (NPP). Their design and the operational practices they support are key aspects of modernizing existing NPPs and meeting the high safety and availability targets set for advanced plant designs. This paper presents a brief history of NPP control room development, and discusses control room improvements planned for the next generation of NPPs     

Increasing capacity of a nuclear power plant unit using the hydrogen-fueled feedwater heating system

The article considers a novel approach to a challenging issue of modern power systems related with the future of nuclear power energy as having clear environmental advantages. To solve the problem, a number of alternative ways of using hydrogen fuel as a source of clean energy were proposed, which are aimed to increase the capacity and maneuverability of operating and designed two-circuit nuclear power plants (NPPs) with installed water coolants. In particular, it was suggested to use hydrogen energy to improve the performance of steam generators and capacity of NPP units by heating the feedwater. The revealed economic benefits of the given approach include the effect from replacing environmentally harmful stations based on gas turbine units. A research was made into the impact of pressure in the hydrogen-oxygen combustion chamber on the effectiveness of the proposed solutions. The necessary design parameters to the hydrogen heating system, the gross and net power ratings of the power unit, and the net present value were determined. It is shown that lowering the pressure in the hydrogen-oxygen combustion chamber leads to the increase in the net present value by 24 to 71 million dollars and by 43 to 90 million dollars for the operating and designed NPPs, respectively. Meanwhile, using the proposed approach to the designed NPPs can ensure a higher capacity for the power units, which equals 179 and 163 MW at atmospheric and elevated pressures, respectively. The efficiency of off-peak energy may equal 26.25 to 27.21 and 26.53% to 27.55% for the operating and designed NPPs, respectively. It should be noted that the proposed schematics prove to be economically competitive across the marginal cost of off-peak energy. The accrued net present value equals 106 to 404 million dollars and 170 to 468 million dollars at the elevated pressure, and 130 to 475 million dollars and 213 to 558 million dollars at the atmospheric pressure for the operating and designed NPPs, respectively.     

生态系统理念在海上风电项目管理中的应用研究

  [目的]  中国海上风电行业已迈入快速发展期,如何创新项目开发管理模式,有效应对海上风电造价高、界面多、工期长等问题,实现成本降低、效能提升,是推动海上风电行业健康快速发展的重要保障。  [方法]  通过将生态系统理念应用到海上风电场项目开发建设和运营管理中,探索构建海上风电场生态系统,以搭建风电场神经网络为核心,提高整体关联效能,实现最优开发目标;利用层次分析法对系统影响因子权重进行定量分析。  [结果]  通过海上风电场生态系统的构建,使海上风电场具备信息快速的收集、存储、共享、分析和反馈调节功能,降本增效,提升风电场稳定性。  [结论]  生态系统的引入为海上风电项目的开发管理和提供了新的思路,借助人工智能技术等前沿科技的发展,海上风电场生态系统也将不断完善和广泛应用。     

Analysis of earthquake management design for nuclear power plants (NPPs) incorporated with artificial intelligence (AI) method

It has been studied to analyze the operations in nuclear power plants (NPPs) where the human error could make a trigger to the nuclear disaster following the earthquake in South Korea. The earthquake warning system and its related control algorithm are modeled by the machine learning (ML) of artificial intelligence (AI) where the neural networking is done as a major role. The AI-based control system could give the very good performance in the earthquake incident which is shown by the system dynamics (SD) based simulations. Hence, the nuclear safety system needs the AI based alarming technology which could be a much more advanced control system incorporated with the conventional multiple-barrier concept in NPPs.