某新建火电机组低压缸零切除控制策略分析及设计

为实现某新建机组在低压缸零切除情况下的安全、经济运行,控制策略的设计是其中的重要一环.依据某新建机组调试期间所遇到的问题,提出了中低压缸联通管蝶阀逻辑、中低压缸旁路调门逻辑、抽汽快关调门逻辑的设计及优化工作,实现了新建机组在低压缸零切除方式下的安全运行.     

浅析1000MW机组供热一次调频控制应用

1000MW机组经过热网系统的改造后,需要更大的抽汽量被供热使用,低压缸负荷调节幅度及响应速度降低,导致机组响应一次调频能力减弱。结合电厂实际运行情况,对供热调门进行适当优化,作为一次调频能力的补充手段,为机组安全经济运行提供了保障。     

660 MW机组真空严密性不合格原因分析及处理

针对某660 MW超超临界二次再热3号机组调试期间发生真空严密性试验不合格的情况,通过对怀疑区域检漏、调整、分析,发现汽轮机主汽门、调门门杆处漏空气是导致真空泄漏及真空严密性试验不合格的原因。通过在超高压主汽门、高压主汽门、中压主汽门、高压调门、中压调门门杆漏汽至凝汽器管道上增加电动真空截止阀,设置压力测点,以及增设逻辑控制截止阀的开关等措施,有效地解决了3号机组真空严密性试验不合格的问题。     

中间再热机组一次调频特性研究

针对电网频率变化大,并网机组一次调频性能差的现象,对中间再热汽轮机组的调节系统进行设计,将频差信号以前馈信号的方式叠加到高压调门和中压调门指令上,让中压调门和高压调门同时参与一次调频,充分利用中间再热容积中的蓄热。仿真结果显示,设置了高、中压调门前馈信号后,中间再热机组的一次调频性能得到了很大程度的改善,负荷响应能力显著提高,调节系统的稳定性能良好,但要实现中压调门前馈信号的控制方式则还需要完成相关的研究工作。     

汽轮机一次调频性能不稳定故障的诊断及解决

针对亚临界300MW汽轮机出现的一次调频性能不稳定问题,进行了高调门流量特性的综合测试诊断,结合理论分析发现了高调门存在硬件间隙故障,找到了调频性能不稳定的根源所在。当机组高调门存在硬件链接不紧密故障时,不仅会引起负荷突变故障,而且还会导致一次调频性能不稳定。然后,针对机组实际调门故障情况,基于阀门重组策略设计了新的顺序阀规律,不仅能够兼顾机组调频性能问题,而且能够使1号、2号瓦的瓦温和轴振值维持在原有稳定水平。因此,该测试方法及优化策略具有一定的有效性及应用价值。     

600MW汽轮机高调门蒸汽室壳体有限元计算与分析

建立600MW汽轮机高调门蒸汽室壳体三维实体模型,根据高调门实际工作环境,利用有限元软件ANSYS,对高调门蒸汽室壳体在机组额定工况以及冷态启动时的温度场进行模拟分析,进一步计算得到了高调门蒸汽室壳体的应力分布规律,并将两种不同工况下计算得到的高调门蒸汽室壳体的温度场和应力场进行了对比分析,为阀门的性能以及安全运行的分析提供理论基础。     

六高调门配置汽轮机喷嘴进汽模式对轴系稳定性影响的试验研究

首先针对六高调门汽轮机调门局部进汽模式下的配汽不平衡汽流力进行理论分析,在典型六高调门配置汽轮机调门开关试验的基础上,得到六高调门配置汽轮机进汽模式对轴系稳定性的基本影响规律:喷嘴配汽采用上缸进汽和下缸进汽时,后面开启的3个高调门存在一个最优开启顺序;极端情况下,还可采用两阀联合调节进汽模式;然而,对角进汽模式对轴系稳定性的影响仍为最小。这对在国内占一定比例的六高调门配置大功率汽轮机安全高效运行优化具有一定借鉴意义。     

基于阀位的主蒸汽流量计算可行性研究

对利用调门综合阀位计算主蒸汽流量需要解决的问题进行了分析,借助某汽轮机正规试验数据,建立了阀位与流量关系的数学模型,并对其相关性、重现性进行了检验。结果表明,当调门重叠度设置合理时,主蒸汽体积流量与综合阀位相关性较强;当调门系统未改变时,调门流量特性重现性较好;主蒸汽流量可由调门综合阀位和主蒸汽参数来求得,作为主蒸汽流量间接测量计算的又一方法,可用于日常离线分析计算。     

1000MW超超临界机组单侧中压调门异常关闭应对策略

根据国内首台1 000 MW超超临界机组的实际运行经验,并针对汽轮机单侧中压调门异常关闭后对机组参数的影响,介绍了汽轮机单侧中压调门异常关闭的处理过程和应对策略,并对华能玉环电厂中压调门的动作原理进行了介绍,可为同类型机组单侧中压调门异常关闭后如何快速判断和事故处理提供借鉴。     

汽轮机通流部分的故障诊断

吴泾热电厂11号机组大修后运行一个余月，进行常规的主汽门和调门松动试验，发现机组在6个调门全开下，负荷只能达到296MW。针对这一现象，通过对试验前后和大修前后的运行数据对比分析和理论计算，成功诊断出故障所在位置、发生时间和严重程度，为检修赢得了宝贵的时间。图5表3     

Electroless platinum and palladium deposition over alumina coated stainless steel plates and their catalytic activity for hydrogen mitigation in severe nuclear accidents

This work focused on platinum and palladium-based autocatalytic plates, which used to remove hydrogen. The six sandblasted stainless steel plates were coated with platinum and palladium metals using the electroless coating method. The three plates A-01, A-02, A-03 were first coated with alumina using the sol-gel dip method, and after that, different ratios of platinum and palladium were deposited on them. The three other plates, B-01, B-02, B-03 (without alumina coated), were coated directly with different ratios of platinum and palladium. The platinum and palladium ratio used for coating these plates were Pt 80%: Pd 20%; Pt 90%: Pd 10%, and Pt 70%: Pd 30. The coating of these plates was characterized using Scanning Electron Microscopy, X-rays Fluorescence Spectroscopy, and their catalytic efficiency was measured by the Passive Autocatalytic Recombiner testing rig method. It was found that the plates coated with alumina using two dipping cycles are suitable for different coating of mixed metals by electroless coating method compared to three dipping cycles. It was observed that the alumina-coated catalytic plates (A-01, A-02, A-03) exhibited excellent catalytic efficiency as compared to those without alumina-coated plates (B-01, B-02, B-03). Furthermore, the catalytic efficiency of A-03 and B-03 is higher than other plates. It was also found that the catalytic efficiency of A-03 is higher than B-03. The best coating ratio is Pt 90%: Pd10%, and alumina-coated plates give excellent results.     

Photo-fermentative hydrogen production performance of a newly isolated Rubrivivax gelatinosus YP03 strain with acid tolerance

Screening and excavating new photosynthetic bacteria with excellent hydrogen production performance is extremely important for improving the photo-fermentative hydrogen production. A new photosynthetic bacterium YP03 was isolated and identified to be Rubrivivax gelatinosus by morphological characterization and phylogenetic analysis. The effects of several key factors on hydrogen production performance were carried out. The results indicated that YP03 strain showed a preference for the carbon sources, and 5375 ± 398 mL/L of maximum hydrogen yield was obtained using butyrate medium. Meanwhile, YP03 strain could use several nitrogen sources to produce hydrogen, and glutamic acid was the optimum nitrogen source for hydrogen produced. Furthermore, YP03 exhibited better hydrogen production performance at initial pH 7.0, reaction temperature 33 °C and light intensity 5000 lux, and the maximum hydrogen production rate was 108.3 ± 12.4 mL/(Lh), which was relatively high compared with the previous reports by R. gelatinosus. Especially, the proper pH for hydrogen production by YP03 ranged from weak acid to neutral (6.5–7.0) and it still could produce hydrogen at pH 5.5 showing the characteristic of acid tolerance. It suggested that YP03 is a potential candidate for the integration of dark- and photo-fermentative hydrogen production. These findings contribute to our understanding of YP03 strain and provide a prospective photosynthetic bacterium for efficient hydrogen production in future research.     

几种空气源热泵热水器工质的实验研究

对三种混合工质(TJM01、TJM02、TJM03)的基本物理性质、安全环保性及溶油性进行了分析,又通过实验对三种混合工质的循环系统性能进行了分析。分析结果表明,三种混合工质在安全环保性和溶油性方面的差别都很小;在基本物性方面,TJM03较好;在系统性能方面,TJM03性能较好,而TJM01性能一般,TJM02性能较差。     

6F.03型燃气轮机现场安装要点分析

据统计,6F.03型燃气轮机在全球已销售200余套。由于6F.03型燃气轮机发电量和耗气量适中,效率媲美9F型燃气轮机,赢得了中国市场的青睐。未来几年,我国将迎来6F.03型燃气轮机的安装高峰。本文结合现场实践,分析并探讨了6F.03型燃气轮机的安装方法和流程。     

The Symplectic Semigroup and Riccati Differential Equations

In this paper, we study close connections that exist between the Riccati operator (differential) equation that arises in linear control systems and the symplectic group and its subsemigroup of symplectic Hamiltonian operators. A canonical triple factorization is derived for the symplectic Hamiltonian operators, and their closure under multiplication is deduced from this property. This semigroup of Hamiltonian operators, which we call the symplectic semigroup, is studied from the viewpoint of Lie semigroup theory, and resulting consequences for the theory of the Riccati equation are delineated. Among other things, these developments provide an elementary proof for the existence of a solution of the Riccati equation for all t ≥ 0 under rather general hypotheses. 2000 Mathematics Subject Classification. 49N10, 93B27, 93B03, 22E15.     

Heat flow near Orlando,Florida and Uvalde,Texas determined from well cuttings

Heat flow has been determined in a borehole near Orlando. Florida and another near Uvalde, Texas. Thermal conductivities in both boreholes were obtained by divided-bar measurements on rock discs and by needle-probe measurements on rock chips. For the needle-probe method, the rock chips were pulverized into powder, saturated with water, and the conductivity of the solid rock was obtained from the conductivity of the mixture by an empirical relationship. Divided-bar measurements for the Florida borehole indicate a heat flow of 0.92 = .03 H.F.U., while needle-probe measurements on rock chips show a heat flow of 1.24 = .06 H.F.U. The discrepancy is attributed to anisotropy of the sedimentary rocks penetrated by the borehole. Heat flow obtained from these two different methods of determining conductivity show good agreement in the Texas borehole. Divided-bar measurements indicate a heat flow of 1.08 = .03 H.F.U. while the chip technique gives a value of 1.13 = .03 H.F.U.     

Local Bifurcations of Control-Affine Systems in the Plane

The phase portrait of a control-affine system, being an almost complete feedback invariant, carries the information on time-optimality and controllability structure of the system. In the paper, we deal with generic control affine systems and 1-parameter families of such systems around stationary points of their controllable part. We classify the portraits of such systems up to homeomorphisms of the state space. In the case of 1-parameter families, the classification embraces bifurcations, which can appear when changing the parameter. The figures illustrating these phenomena are included. The work was partially supported by the European Community Marie Curie Fellowship (in the CTS framework), contract number: HPMT-CT-2001-00278 and KBN grant 2P03A00124.     

燃烧生物质成型燃料采暖热风炉的设计与试验

为弥补华北农村冬季传统采暖存在的不足，根据生物质成型燃料燃烧特性，设计制造出适合燃用生物质成型燃料的专用热风采暖炉，并对其进行了热工性能试验，结果表明，在较好工况下，其燃烧效率可达85.03％～92.06％，热效率可达44．82％～55．85％，为解决农村地区采暖问题提供了有效途径。