概率设计法在汽轮机直叶片级热力设计中的应用

提出了汽轮机直叶片级热力性能的概率设计法。该方法以现有汽轮机直叶片级的热力设计的计算公式为基础,把叶片级的热力设计量根据实际情况处理为随机变量,把概率论和统计学应用于直叶片级的热力设计,旨在准确分析设计和制造因素离散性对叶片级内功率和相对内效率的影响。文中给出了汽轮机直叶计片级３０个热力设计量的均值和标准差的计算公式和应用实例。     

用概率设计方法进行叶片可靠性设计初探

目前试行的《汽轮机叶片振动强度安全准则》的设计方法属于经典的设计方法，即安全系数法，该法没有考虑各种随机因素及离散性的影响，不能定量描述安全裕度。本文用概率设计方法对叶片的可靠性设计进行了理论上的初步探讨和推导，给出了叶片可靠性设计中的一些计算公式，以及由此计算出的叶片的可靠性指标，定量地描述了叶片的安全可靠性。     

面向对象方法在汽轮机级的热力计算程序设计中的应用

在对汽轮机级的热力计算方法进行总结的基础上,分析了不同类型的叶片级的热力计算方法的异同。利用面向对象程序设计的思想,将汽轮机的级的热力计算抽象为一个研究对象,建立了汽轮机级的热力计算模型的基本框架,并详细讨论了其内部的实现过程。通过计算实例验证表明,此方法具有便捷、可靠、界面友好的特点,提高了汽轮机级的热力计算的效率。     

汽轮机扭叶片级间隙气流激振力分析

从流体动力学出发,应用动量定理研究汽轮机扭叶片由于间隙引起的气流激振力问题,同时综合考虑了叶片的各项设计参数,特别是进气角、出气角随时高变化的特点,并应用理论分析的方法导出计算汽轮机扭叶片间隙气激振力的普遍适用计算公式,解决了Alford公式不考虑叶片形式及设计参数,因而不适用于计算扭叶片级间隙气流激振力的问题。     

全三维设计方法的应用

随着计算机技术和计算流体力学的飞速发展，汽轮机通流设计已从二维时代飞跃到全三维设计时代。如今，世界各国汽轮机通流设计技术均建立于3D－NS计算分析的基础上。通流叶片级的3D－NS计算分析软件正成为通流优化及新产品开发时气动设计中重要的工具。东方汽轮机厂基于先进的静动叶型线，利用全三维粘性多级叶轮机计算程序对高压级的新旧设计叶片级作了多个方案的3D－NS计算分析，成功地开发出先进的三维弯曲叶片，并应用于国产3F－200MW汽轮机的通流改造中。经过改造后机组的热力性能试验验证，计算和试验证明全三维设计技术的应用是成功的。     

汽轮机热力性能试验中不确定度的计算

对汽轮机热力试验中诸多测量参数的不确定度和最终试验结果的不确定度进行了分析探讨,并给出相应的计算公式。以姚孟电厂300MW汽轮机热力性能试验为例,进行了实际的主流量、主蒸汽流量、发电机出力、热耗率不确定度的计算。     

汽轮机级效率等参数对功率热耗率影响的分析与计算

本文用小偏差方法对再热——回热汽轮机系统进行了分析,得到级内效率、缸内效率等参数对输出功率、热耗率等参数的影响系数表达式。这在分析机组热力性能和确定改进方向以及计算改进效果方面有一定的用处。     

考虑透平逐级冷却的重型燃气轮机热力学建模及关键参数影响分析

透平冷却系统是现代重型燃气轮机的核心之一，如何考虑冷气掺混影响，是燃气轮机热力学建模和关键参数影响分析中需要解决的首要问题之一。随着燃气轮机总体设计的不断深化，需要更细化的热力性能计算模型，以进行关键部件和总体的协调匹配和保障设计性能的最终实现。为此，提出了基于透平一维气动分析的燃气轮机透平逐级掺混及总体热力性能计算方法，建立了重型燃气轮机热力性能模型，并对关键参数的影响和G/H级燃气轮机热力性能方案进行了研究。分析表明：透平初温、压比和冷却空气量是影响燃气轮机总体热力性能的关键参数，在总体设计中应做到三者统一协调，提高透平初温的同时需研究达到该温度水平需要的最少冷却空气量，分析最佳压比，并结合部件设计进行迭代计算和深入研究后最终确认。该研究结果可为自主化重型燃气轮机总体性能设计提供参考。     

1000MW级空冷机组可行性研究

针对空冷机组的特点,分析空冷汽轮机的主要技术问题,对大型空冷机组设计进行技术总结,在研究湿冷百万机组的基础上,提出1000MW级空冷机组的设计思路,对汽轮机热力系统优化、末级叶片的选择、排汽装置设计、给水泵配置等设计技术进行分析讨论,对其可行性和经济性进行研究。     

基于C++ Builder的600MW汽轮机组热耗率计算程序的开发

根据国家标准GB8117-87与国际最新水和水蒸汽热力性质计算公式,采用反平衡方法推导国产600MW汽轮机组热耗率的计算关系式,并以此编制可视化程序进行了计算,计算结果与汽轮机厂家提供的热力特性参数吻合较好。     

汽轮机热力系统管壳式换热器管束振动的可靠性设计

提出了汽轮机热力系统管壳式换热器管束振动的可靠性设计方法。该方法把流体弹性激振的设计量根据实际情况处理为随机变量,使用概率设计法确定换热器避免流体弹性激振的可靠性。文中给出了高压加热器,低压加热器,凝汽器和汽水分离器防止流体弹性激振的设计判据和避开流体弹性激振可靠度的计算公式以及应用实例。     

Ways for Improving Efficiency and Reliability of Steam Turbines at Nuclear Power Stations

The current state and ways for improving the effectiveness of steam turbine units at nuclear power stations (NPS) are examined. The specifics of NPS turbines is described. The comparison of NPS steam turbine performance with the performance of steam turbines at thermal power stations (TPS) demonstrates that power units of NPSs are much poorer in effectiveness due to relatively low steam conditions at the inlet and the presence of wet steam already in the first stages of turbines. A decrease in the relative internal efficiency of NPS turbines results from the enhanced negative effect of wetness in the expansion process: in modern NPS turbines, more than two-thirds of the heat drop is spent in the two-phase region, while less than one fourth in TPS turbines. It is demonstrated that the effectiveness of NPS steam turbine units can be increased drastically in the future only through a considerable rise in the turbine inlet steam conditions. This can be achieved by using a heat carrier at supercritical conditions in the NPS reactor. The dependence of the effectiveness of NPS modern turbines on the turbine inlet steam conditions in the applicable pressure ranges of the saturated steam and vacuum in the condenser, as well as on the turbine exhaust area, is examined. For a 1000 MW turbine, increasing the inlet pressure from 6.0 to 8.0 MPa raises the turbine power and efficiency by 3.5%. At a condensing turbine outlet pressure ranging from 2.5 to 7.5 kPa and a constant velocity downstream of the last stage, the turbine power and efficiency can be increased by 7%. The importance of the exhaust area for the turbine effectiveness is revealed. Alternative designs of the flowpath in a low-pressure cylinder are analyzed. A unique configuration of a steam turbine unit with two-stage moisture separation is proposed. The comparison of high-speed turbines with low-speed ones was performed. It is demonstrated that the efficiency of the examined turbines is nearly the same within the accuracy of design calculations and the test results, and it is slightly higher for low-speed turbines due to lower losses with outlet velocity.     

变汽温法测300MW机组高中压缸间轴封漏汽量的应用实践

介绍了变汽温法测量国产引进型300MW汽轮机高中压缸间轴封漏汽量的应用实践,分析了高中压缸间轴封漏汽量对热耗率和中压缸效率计算值的影响,提出可以使用此法确定同型新投产机组和改造机组热力性能考核试验中高中压缸间的轴封流量,以及监测机组日常运行时高中压缸前轴封运行状况和中压缸通流效率。     

K-65-12.8 condensing steam turbine

A new condensing steam turbine K-65-12.8 is considered, which is the continuation of the development of the steam turbine family of 50–70 MW and the fresh steam pressure of 12.8 MPa, such as twocylinder T-50-12.8 and T-60/65-12.8 turbines. The turbine was developed using the modular design. The design and the main distinctive features of the turbine are described, such as a single two-housing cylinder with the steam flow loop; the extraction from the blading section for the regeneration, the inner needs, and heating; and the unification of some assemblies of serial turbines with shorter time of manufacture. The turbine uses the throttling steam distribution; steam from a boiler is supplied to a turbine through a separate valve block consisting of a central shut-off valve and two side control valves. The blading section of a turbine consists of 23 stages: the left flow contains ten stages installed in the inner housing and the right flow contains 13 stages with diaphragm placed in holders installed in the outer housing. The disks of the first 16 stages are forged together with a rotor, and the disks of the rest stages are mounted. Before the two last stages, the uncontrolled steam extraction is performed for the heating of a plant with the heat output of 38–75 GJ/h. Also, a turbine has five regenerative extraction points for feed water heating and the additional steam extraction to a collector for the inner needs with the consumption of up to 10 t/h. The feasibility parameters of a turbine plant are given. The main solutions for the heat flow diagram and the layout of a turbine plant are presented. The main principles and features of the microprocessor electro hydraulic control and protection system are formulated.     

汽轮机通流效率与机组热耗率关系的计算

建立汽轮机组变工况热力计算程序,并给出各缸效率与热耗率关系的数学模型,对上海汽轮机厂600 MW超临界汽轮机进行热力计算,分析通流性能变化与热耗率的关系。计算结果显示:级组效率变化与热耗率及本缸效率变化量成线性关系;级组承担功率越大、越靠近排汽端,则级组效率变化对热耗率与本缸效率的影响越大;低压缸效率改变对热耗率的影响最大,高压缸其次,中压缸最低;基于数学模型的计算结果与变工况热力计算基本一致,表明该数学模型计算精度很高。     

Retrofitting Steam Turbines with Expired Service Life

Many pieces of equipment installed at thermal power stations (TPS) have an expired service life or are close to expiry and are obsolete. In addition, the structure of heat consumption by end users has changed. Among the ways for solving the problem of aging equipment is the retrofitting of turbines that allows for service life recovery and improvement of their performance to the modern level. The service life is recovered through replacement of high-temperature assemblies and parts of a turbine, and the performance is improved by retrofitting and major overhaul of low-temperature assemblies. Implementation of modern engineering solutions and numerical methods in designing upgraded flow paths of steam turbines considerably improves the turbine effectiveness. New flow paths include sabre-like guide vanes, integrally-machined shrouds, and effective honeycomb or axial-radial seals. The flow paths are designed using optimization and hydraulic simulation methods as well as approaches for improving the performance on the turbine blading and internal steam flow paths. Retrofitting of turbines should be performed to meet the customers' needs. The feasibility of implementation of one or another alternative must be determined on a case-by-case basis depending on the turbine conditions, the availability of reserves for generating live steam and supplying circulation water, and the demands and capacities for generation and delivery of power and heat. The main principle of retrofitting is to retain the foundation and the auxiliary and heat-exchange equipment that is fit for further operation. With the example of PT-60-130 and T-100-130, the experience is presented of a comprehensive approach to retrofitting considering the customer’s current needs and the actual equipment conditions. Due to the use of modern engineering solutions and procedures, retrofitting yields updating and upgrading of the turbine at a relatively low cost.     

燃气-蒸汽联合循环中蒸汽轮机发电机组的整体调试

燃气-蒸汽联合循环机组近年来被广泛应用,其蒸汽轮机发电系统的主要设备包括余热锅炉、汽轮机以及辅助设备。以PG9171E燃气轮机配套的蒸汽轮机发电机组为例,介绍了设备安装完成后的一系列试验和性能考核工作,并给出了试验结果。     

适应整体煤气化联合循环燃气轮机改型方法分析

整体煤气化联合循环(IGCC)是多种设备、多种技术集成的一个复杂系统,整合了化工、发电等各方面技术为一体,包括了气化炉、空分系统、燃气轮机、余热锅炉、蒸汽轮机等设备。通过分析煤气化合成气与天然气的差异以及煤气化合成气对燃气轮机的影响,展开燃用天然气燃气轮机改型设计为燃用合成气的方法探索,总结改型设计经验,为整体煤气化联合循环燃气轮机设计奠定基础。     

火电机组排汽焓在线计算方法的研究

根据火电机组热经济性在线监测的特点 ,利用熵增原理 ,结合温熵图、热力单元矩阵分析法和等效热降理论对汽轮机排汽焓的计算方法进行探讨 ,实现了火电机组在线监测系统中汽轮机排汽焓的在线计算 ,为机组实时热经济性分析提供了依据。图 3表 2参 9。