新型水火管蒸汽锅炉汽水分离特点与效果

提出十分简单的汽水分离措施,使蒸汽湿度低于0.5%。我国标准规定水火管锅炉和锅壳锅炉的蒸汽湿度不应大于4%,是明显偏高,建议对此给予修改。     

角管式蒸汽锅炉再循环管的实验研究

通过对角管式蒸汽锅炉侧墙水冷壁的循环原理进行分析,找到了影响再循环管水动力特性的主要因素,并建立了水动力特性实验台,对热负荷和预分离集箱影响再循环管作用的规律了实验研究。     

亚临界压力自然循环锅炉水循环问题研究

本文介绍了由专用源程序计算的一台3×10~5kW 亚临界压力自然循环锅炉的水循环情况,包括不同的下降管径,水冷壁热负荷及汽包运行压力为20.3MPa等各种工况。并进行了讨论,得到一些有意义的结论。     

直流盘管式蒸汽锅炉管子泄漏失效分析

某酒店的立式强制循环盘管式直流锅炉,频繁出现盘管泄漏事故,在对该炉的结构和使用情况进行详细分析的基础上,对泄漏部位进行了检查和分析,确定吸氧电化学腐蚀、汽蚀和流动加速腐蚀是造成事故的主要原因,并有针对性地提出了防护和改进措施。     

自然循环热水锅炉水动力研究

本文提出的自然循环热水锅炉水动力计算方法包括了简单回路、并联回路、结构不均的典型回路和下降管入口水温的计算,并且考虑了热力不均及水力不均的影响。通过试验分析提出了防止气泡贴壁和产生过冷沸腾的条件。     

Experimental and Numerical Investigation on a Two-Phase Natural Circulation Test Facility

A geometrically similar model of the proposed Advanced Heavy Water Reactor being designed and built by Bhabha Atomic Research Centre has been conceived and built at Indian Institute of Technology, Bombay. The basic objective of setting up such a facility and conducting experimental studies was to simulate the thermal-hydraulic behavior during the startup and also during part or full power operation. Owing to hydrodynamic instabilities observed in natural circulation system, it is necessary to know the stability boundaries. In this paper, the details of the experimental facility, experimental studies, and numerical simulations carried out using RELAP5/MOD 3.2 are discussed. Type I and type II stability boundaries and stable two-phase operation zones have been experimentally obtained at various pressures and inlet subcooling and the results are correlated using appropriate nondimensional numbers. Further, the experimental facility is modeled using the thermal-hydraulic code RELAP5/MOD 3.2. The single-phase pressure drops measured in the loop are used to estimate the appropriate loss coefficients used in the model. The model is then used to predict stability boundaries, and the predictions are compared with the experimental findings. The details of the experimental model and simulation results are presented. The capability of RELAP5/MOD 3.2 to predict the flow oscillations during instabilities is discussed.     

自然循环热水锅炉射流装置的数值模拟研究

结合生产的实际需要,利用FLUENT软件对自然循环热水锅炉射流装置的工作过程进行了数值模拟,并通过对相关参数的监测,给出了各参数对射流装置工作效能影响的规律。     

自然循环锅炉整体动态特性分析

运用理论分析和经验归纳结合的方法,系统总结并提炼出了一整套自然循环锅炉的整体动态数学模型,并编写了相应的实时仿真程序。     

Two-Phase Natural Circulation Loops: A Review of the Recent Advances

The wide range of applications of two-phase natural circulation loops (NCLs) demands intense analyses of boiling systems, and consequently a large number of experimental and theoretical research findings are available in the literature. This comprehensive review focuses on the state-of-the-art appraisal of the related technology, with a primary focus on studies carried out in the last two decades. General modeling strategies have been reported and compared. Different forms of thermal-hydraulic instabilities appearing in two-phase NCLs have been summarized, with discussions on possible ways of identification and their differences. In addition, studies on system instability are presented in a categorywise grouping following a chronological style in terms development of knowledge. Coupled nuclear instabilities are reported as well in some detail. Finally, this review identifies the gray areas where the information is not quite complete and suggests the required path of future research.     

亚临界自然循环水动力特性的分析

结合国内外锅炉生产厂家的亚临界自然循环锅炉水动力计算数据和已经运行的亚临界自然循环锅炉的运行测试数据,对锅筒压力和循环回路的结构特性如水冷壁管内径、循环回路高度、下降管和引出管与上升管的截面比等对亚临界自然循环锅炉水循环特性的影响,管子内壁粗糙度、局部阻力系数、锅内旋风分离器阻力、锅筒凝汽率等参数在水循环计算时的选取,...     

Effect of Chemical Cleaning on Steam Generator Tube Performance

Boiling experiments were performed on new, chemically cleaned, and fouled steam generator tubes to determine the heat transfer performance of each. It was found that the heat transfer performance of the fouled tube was the best, followed by the chemically cleaned tube. The performance of the new tube was the worst. Scanning electron microscope (SEM) photographs of the boiling surfaces were taken to identify differences in surface characteristics. Results revealed the presence of significant amounts of porous deposits on the surface of the fouled tube that provided ample nucleation sites for boiling. Chemical cleaning removed most of the deposits such that the boiling performance of the cleaned surface was degraded. The new tube was very smooth and there were relatively fewer nucleation sites as evidenced in the SEM photographs. Available correlations were used to predict the heat flux for a given wall superheat and were compared with the experimental data.     

CFB锅炉的循环倍率

循环倍率是ＣＦＢ锅炉设计和运行的重要参数，但目前并存着两种不同的定义。本文分析了两种不同定义的循环倍率之间的数值关系，指出两种定义并存可能造成的问题，并对如何取舍提出了建议。     

600MW自然循环锅炉屏式过热器爆管分析

针对600MW锅炉分隔屏过热器上升管频繁超温爆管的问题,分析了发生爆管的主要原因,提出了切实可行的改造方案及对策。     

汽轮机中湿蒸汽两相凝结流动研究

在汽轮机湿蒸汽透平级中,湿蒸汽两相凝结流动现象的出现降低了透平级的流动效率,并且造成了透平叶片的水蚀损坏.本文针对汽轮机中的自发凝结流动,介绍了湿蒸汽两相流动数值研究发展的现状,以及西安交通大学TurboAero研究组在此方面的研究情况,以期对我国湿蒸汽汽轮机的设计以及湿蒸汽两相凝结理论的工程应用起到推动作用.     

循环流化床锅炉循环倍率软测量研究

循环倍率对循环流化床(CFB)锅炉运行状态监测和关键参数控制具有重要作用,但其难以直接测量.针对此问题提出一种循环倍率的软测量方法,通过对炉内化学过程和床内物料循环过程进行机理分析,依据质量守恒定律建立平衡方程并对其进行简化,进而计算出炉内飞灰份额、分离器分离效率等关键中间变量,最后通过仿真得到循环倍率.结果表明:循环倍率与单位负荷下稀相区的颗粒密度存在线性关系;循环倍率软测量方法计算值与锅炉设计值非常接近,证明了循环倍率软测量方法的可行性和有效性.     

自然循环热水锅炉水动力回路分析法的计算原理

1前言自然循环热水锅炉在我国得到了广泛的应用。为了保证热水锅炉的安全运行,必须对其进行水动力计算。长期以来,自然循环热水锅炉水动力计算使用的方法是图解法[1],该方法将锅炉受热面划分成若干个管组,假定每管组内的各单管具有相同的热负荷和结构参数,然后对各个管组进行水     

自然循环锅炉启动过程中过热器超温机理的研究

根据热量平衡原理,提出了一种简单直观的计算分析计算方法对锅炉启动过程中的过热器超温的原因进行了分析和化证。其结论与实际的测量结果一致。该结论揭示了锅炉启动过程中过热器超温的实质,对过热器超温机理的研究和提出解决过热器超温的措施有一定的参考价值。     

汽轮机湿蒸汽两相凝结流动数值研究的现状与进展

着重针对汽轮机中存在自发凝结的湿蒸汽两相流动 ,论述了湿蒸汽两相流动数值研究进展现状及其待解决的问题 ,以期对此方面的研究及其工程应用起到促进作用。文中结合作者目前进行的有关湿蒸汽两相凝结流动数值研究 ,对湿蒸汽透平级中两相流动的数值模型、求解方法等关键问题进行了阐述和探讨 ,给出了作者对一维喷管、二维喷管以及叶栅进行数值模拟的部分算例结果 ,以说明所发展的数值模拟方法的可行性和准确程度。     

锅炉排汽管口裂纹原因及处理方法

针对某一发电锅炉排汽管口裂纹,分析了造成缺陷的原因及处理方法,并提出了防止出现这种缺陷的措施。     

超超临界锅炉的汽温偏差探析

根据实际运行数据研究了超超临界锅炉的汽温偏差变化规律和影响汽温偏差的特殊因素。指出特殊因素为:在湿态向干态转变和跨越临界点时工质热物理特性变化大;过热器系统的蒸汽流程延长、汽温偏差的累积效应增大;水煤比变化等;必须注意单侧减温水量过大,将加剧流量偏差,甚至引发临界流,进而扩大汽温偏差。实例反映的汽温偏差变化趋势为:超临界锅炉在低负荷运行阶段汽温偏差最大;在临界压力附近,汽温偏差被放大;在90%负荷以上过热器出口汽温偏差可以控制在低于5℃的设计值。对于制造、安装和焊接等工艺质量引起的超温爆管或流量偏差更要高度重视。