船用核动力汽轮机组耦合变工况特性及其影响因素研究

船用核动力汽轮机组变工况运行特性的好坏直接影响其机动性、可靠性、经济性等重要指标。为此,首先给出汽轮机调节级逆顺序变工况算法和压力级组变工况算法,并提出一种能够全面考虑汽轮机喷嘴+节流+滑参数调节方式、多参数变化的多级汽轮机组变工况分析模型;然后基于动态模型的冷凝器变工况分析方法,建立一种通用型模块化的汽轮机和冷凝器耦合变工况分析模型;随后,将该耦合变工况模型应用于某船用核动力汽轮机组的变工况特性研究,分析不同外界因素对机组变工况特性的影响。结果表明,建立的汽轮机组变工况模型能够真实地反映各设备之间的强耦合关系,有效地实现了船用核动力汽轮机组全工况范围的变工况分析,并指明运行参数对汽轮机组变工况的影响机理和程度,为船用核动力汽轮机组的优化设计、高机动可靠运行提供了强有力的支撑。     

极低负荷工况下单缸核湿汽轮机末三级流动特性分析

基于Bladegen-Turbogrid实体叶片参数化建模方法与叶栅流道结构化网格划分方法,采用两相均质数值模型与湿蒸汽平衡相变模型,对不同容积流量工况下船用核动力湿汽轮机末三级进行了全三维定常数值计算,重点分析了极低负荷工况下湿汽轮机末三级的流动特性.结果表明:随着容积流量的降低,湿汽轮机末三级级内蒸汽流动紊乱度增加...     

船舶饱和蒸汽轮机动态特性仿真

介绍了船舶饱和蒸汽轮机功率、转速全工况实时仿真模型。该模型基于各守恒定律和水蒸汽物性,考虑了蒸汽的可压缩性、机内实际膨胀过程和调节级变工况特性的影响。仿真结果表明该模型稳态精度高、动态趋势合理,适用于核动力装置全工况范围正常运行和异常事故运行,此模型已在一台船舶核动力装置模拟器上得到了成功的应用。     

用于汽轮机甩负荷动态计算的数学模型

汽轮机甩负荷动态计算对机组的安全运行起着很重要的作用。建立汽轮机模型进行仿真分析是汽轮机甩负荷动态计算的主要方法。但是现有的汽轮机模型用于甩负荷工况还存在一些问题。考虑甩负荷工况下由强扰动引起的非线性特性,以及OPC信号和回热器对汽轮机的影响,给出了建立用于汽轮机甩负荷动态计算的数学模型的方法,并以某汽轮机为例进行了仿真分析。     

360MW机组汽轮机实时模块模型的建立与研究

基于MMS仿真环境,以360MW发电机组汽轮机系统为对象,建立了汽轮机实时动态模型,并对该模型进行了仿真试验以及动态特性分析。仿真试验结果表明,模型能达到实时的要求,动态响应符合对象的机理。     

基于Modelica/Mworks的船用汽轮机主汽门性能仿真验证

基于面向对象的多领域统一建模开源规范Modelica/Mworks平台，通过研究船用汽轮机主汽门性能仿真数学模型，构建了针对船用汽轮机主汽门的图形化仿真模型，并开展了数据可视化仿真及验证。模型仿真结果表明，仿真模型具有良好的模块化特征和可重用性，能够正确地反映主汽门的全行程流量曲线等运行特性；充分验证了模型的有效性，为船用汽轮机主汽门和汽轮机整机仿真研究奠定了基础。     

基于实时稳态模型的汽轮机冷端系统闭环优化控制

汽轮机冷端系统是火电机组的重要辅助系统,其运行状态的好坏直接关系到机组的安全、经济运行。分析汽轮机冷端系统的换热机理,通过对汽轮机末级变工况计算模型、凝汽器换热变工况计算模型以及变频循环水泵变工况特性分析,建立汽轮机冷端系统最佳真空稳态计算模型。分析了机组在不同边界条件下的最佳运行真空,进而利用稳态计算模型构建最佳真空闭环优化实时控制系统,实现对机组循环冷却水流量的连续调节,提高了机组的运行经济性。     

某船用汽轮机短座阀流量与提升力特性数值模拟计算

由于汽轮机内部空间的限制及船用汽轮机多工况的要求,部分船用汽轮机采用了短座阀。因扩压段长度的大幅减小．阀门的气动性能及强度振动特性产生较大变化,对汽轮机总体性能有较大的影响。本文对某短座阀在试验研究的基础上进行了数值计算分析：通过气动试验,得到某船用汽轮机短座阀的流量系数与提升力系数曲线簇;基于可压缩,N-S方程,利用S-A湍流模型及有限积分法,采用四面体非结构性网格．对此阀门进行了数值模拟计算。通过对该阀门的数值计算得到在不同相对开度及不同压比下的计算结果与试验结果吻合良好;得到对各种短座阀广泛适用的计算方法．为船用调节阀、旁通阀的设计和性能分析提供了重要依据。     

考虑重叠度的汽轮机调节级变工况改进算法

汽轮机调节级变工况计算对汽轮机的热力校核和在线仿真具有重要意义。通过对调节阀联合升程流量特性的分析,建立相邻两个不完全开启调节阀的流量计算模型,并引入到调节级变工况计算中,提出考虑重叠度的汽轮机调节级变工况改进算法,解决以往重叠区内工况无法计算的问题,保证机组在线仿真的连续性。对国产200MW机组进行调节级变工况计算,结果表明:计算误差在工程设计要求的范围之内,最大为3.07%。     

基于改进型人群搜索算法的船用二回路系统效率优化研究

为提高船用核动力装置二回路系统的热效率,根据船用核动力装置特点建立了二回路系统数学模型,借助MATLAB软件编制了效率评价函数。提出了一种能够增强改进型人群搜索算法,并用标准测试函数对改进型SOA进行试验,验证了算法寻优的快速性和精确性。在二回路系统寻优计算中以系统效率最高为目标,设置4个约束条件,在三维空间内搜索,得出了优化变量的最佳组合,进而得到了系统中各耗汽设备的耗汽量、热负荷、换热节点温度等参数,使系统效率提高了1.8%,最后对优化方案给系统效率造成的影响进行了分析。研究成果表明提出的方法能够实现二回路系统效率的提高,为核动力装置效率优化提供了思路。     

基于3KEYMASTER软件的核电站汽轮机数学模型与仿真

以福建宁德1000 MW核电机组汽轮机为研究对象,经过系统划分和对具体物理设备进行合理简化和假设后,建立了汽轮机组的动态数学模型。在3KEYMASTER仿真平台上进行了论证,经测试该模型能够正确反映核电站汽轮机的动态特性。     

AP1000核电厂二回路热力系统计算与分析

针对核电二回路系统与常规火电机组热力系统在参数设定、热力特性等诸多方面的差异,本文基于ASME PTC-6等相关标准要求,以某AP1000压水堆核电机组为研究对象,首先对该机组二回路热力系统热耗保证工况(turbine heat-acceptance,THA)下的表征算法进行研究,其次对不同设计工况下的特性参数进行计算,并在此基础上建立了核电机组二回路系统热力性能评估分析模型。随后应用该模型对案例机组在某一实际运行工况下的热力特性进行详细计算,在该运行工况下,低压缸第八级段、第九级段特征通流面积(CFA)较设计值偏差大,分别为6. 38%和17. 07%,其余级段偏差均在合理范围内,由此可初步判定第八级段、第九级段发生故障。     

核电凝汽器防泄漏措施

作者在岭奥核电站从事核电辅机的设计及开发,对核电的主要辅机凝汽器进行了深入的研究,认识到核电凝汽器的水侧至汽侧的严密性至关重要,它直接影响到机组的安全运行。本文作者从其亲身参加电站机组运行的经历,及针对核电凝汽器发生的问题的现场处理,就影响核电凝汽器的密封性能的几个因素进行了分析,并提出了一些防止凝汽器泄漏的措施,期望能为广大的核电工作者及辅机设计者借鉴。     

浅谈火电厂汽轮机运行故障处理技术

汽轮机作为火力发电厂三大主机之一,其安全运行关系着整个系统的经济性和安全性.汽轮机在运行过程中不可避免地会出现很多故障.介绍了火电厂汽轮机的工作原理,总结归纳了汽轮机运行中常见的几种故障及处理措施技术,以期为从事汽轮机运行及检修的人员提供参考.     

Comprehensive assessment of system efficiency and competitiveness of nuclear power plants in combination with hydrogen complex

The strategy provides construction and commissioning of a number of new nuclear power units for the development of nuclear energy in Russia. The share of nuclear power plants increase in the energy systems of Russia is predicted from 19 to 22% in the future, up to 2050. Nuclear power plants planned to involve in the primary frequency control at the same time. All these circumstances exacerbate the problem of providing nuclear power plants with a basic electrical load in the night period, including during the daily period. The energy strategy of Russia provides for the production of hydrogen by low-carbon methods, one of which is water electrolysis using nuclear power. Hydrogen production is included in the development strategy of the at operating Russian NPPs. Hydrogen production planned at the Kola NPP by water electrolysis. Thus, the article provides a rationale for the effectiveness of combining nuclear power plants with a hydrogen complex based on the production of hydrogen by electrolysis of water. The effectiveness substantiated of the new principle of combination with overheating of the working fluid steam turbine cycle of the NPP taking into account the safety of handling hydrogen. A new system proposed for the combustion of hydrogen in oxygen, which makes it possible to overheat the working fluid of the NPP steam turbine cycle with undissociated steam, which significantly reduces the content of unreacted hydrogen in the working fluid flow. In addition, a system was developed and proposed for removing unreacted hydrogen and oxygen from the steam phase of the working fluid of the NPP steam turbine cycle. Thermodynamic and technical-economic new estimates are presented and analyzed of the efficiency of combining NPP with a hydrogen complex.     

Energetic and exergetic analysis of a hybrid combined‐nuclear power plant

Combined‐cycle power plants are currently preferred for new power generation plants worldwide. The performance of gas‐turbine engines can be enhanced at constant turbine inlet temperatures with the addition of a bottoming waste‐heat recovery cycle. This paper presents a study on the energy and exergy analysis of a novel hybrid Combined‐Nuclear Power Plant (HCNPP). It is thus interesting to evaluate the possibility of integrating the gas turbine with nuclear power plant of such a system, utilizing virtually free heat. The integration arrangement of the AP600 NPP steam cycle with gas turbines from basic thermodynamic considerations will be described. The AP600 steam cycle modifications to combine with the gas turbines can be applied to other types of NPP. A simple modeling of Alstom gas turbines cycle, one of the major combined‐cycle steam turbines manufacturers, hybridized with a nuclear power plant from energetic and exergetic viewpoint is provided. The Heat Recovery Steam Generator (HRSG) has single steam pressure without reheat, one superheater and one economizer. The thermodynamic parameters of the working fluids of both the gas and the steam turbines cycles are analyzed by modeling the thermodynamic cycle using the Engineering Equation Solver (EES) software. In case of hybridizing, the existing Alstom gas turbine with a pressurized water nuclear power plants using the newly proposed novel solution, we can increase the electricity output and efficiency significantly. If we convert a traditional combined cycle to HCNPP unit, we can achieve about 20% increase in electricity output. This figure emphasizes the significance of restructuring our power plant technology and exploring a wider variety of HCNPP solutions. Copyright © 2011 John Wiley & Sons, Ltd.     

300MW燃煤电厂热力系统仿真研究

基于过程系统工程的建模和仿真原则,针对某电厂300MW燃煤机组开发了一套稳态热力学仿真系统,并详细阐述了模型建立的基本思路和方法,通过改变输入参数、负荷和环境条件,仿真电厂在不同工况下的运行特性．结果表明：系统仿真所获得的结果与实际电厂的性能测试数据相比误差不超过2％;通过仿真可获得主要物流、能流的热力学参数（包括质量流量、温度、压力、比焓、比熵等）和主要设备的运行参数（包括汽轮机和泵的等熵效率、加热器端差、热传导系数等）,为燃煤电厂的实际运行优化、炯分析、热经济学分析等提供基础数据．     

寒冷地区闭合空气幕防寒保温特大门设计研究

为了满足寒冷地区核电汽轮机厂房的设备正常运行和电厂安全,以辽宁红沿河核电厂汽轮机发电厂房特大门为例,探讨了在寒冷地区核电常规岛汽轮发电机房一种闭合空气幕防寒保温特大门的构造做法。通过使用该大门能够减少能耗损失,满足核电厂汽轮发动机厂房边界温度大于等于5 ℃最低要求,每天节约标煤85 kg左右。     

Energy performance enhancement of solar thermal power plants by solar parabolic trough collectors and evacuated tube collectors-based preheating units

Solar steam power plant is the dominant technology in the category of solar thermal power systems. In steam power cycles, there is usually a couple of steam lines, extracted from medium-pressure and low-pressure turbines, to preheat the working fluid before the boiler. This although leads to an increase in the energy efficiency of the cycle, reduces the contribution of the turbine proportionally. Therefore, finding an alternative method of preheating the working fluid would be effective in further enhancement of the efficiency of the system. In this study, the feasibility of using solar collectors for the preheating process in a solar steam power plant is investigated. For this, parabolic trough solar collectors and evacuated tube solar collectors based on a wide range of different scenarios and configurations are employed. The plant is designed, sized and thermodynamically analyzed for a case study in Saudi Arabia where there is a large solar irradiation potential over the year. The results of the simulations show that, among all the considered scenarios, a power cycle aided by a set of parabolic trough collectors as the preheating unit is the best choice technically. This configuration leads to about 23% increased power generation rate and 6.5% efficiency enhancement compared to the conventional design of the plant.