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1.
某空冷600MW汽轮发电机组是国内首台完全自主开发设计的全新机组,本文针对某空冷600MW汽轮发电机组低压转子采用落地轴承结构,对轴系安全裕度的影响进行了计算和分析。计算结果表明:采用落地轴承有利于提高某空冷600MW机组轴系的安全裕度。  相似文献   

2.
袁永强  潘家成 《热力透平》2006,35(4):257-261,292
主要研究了空冷600MW汽轮发电机组轴系扭振特性、疲劳寿命损耗,并针对两个特定电厂的接入系统进行网机耦合次同步谐振特性分析。轴系扭振频率和响应计算采用连续质量模型,次同步谐振特性分析采用集中质量模型。计算结果表明,机组扭振频率避开了工频和倍频,轴系不会因共振而破坏;在短路故障轴系扭振是安全的;空冷600MW汽轮发电机组可以用于远距离输电在线路中进行串联电容器补偿。  相似文献   

3.
针对三缸超临界空冷汽轮发电机组轴系振动特性进行分析,结果证明机组的安全可靠性达到先进水平。  相似文献   

4.
谷伟 《汽轮机技术》2006,48(1):71-72
通过对天津大港发电厂两台进口意大利328.5MW汽轮发电机组调节、保护系统改造方案的分析,总结了328.5MW机组调节、保护系统改造的特点和经验。  相似文献   

5.
直接空冷机组真空严密性试验方法及漏空原因分析探讨   总被引:1,自引:0,他引:1  
续宏 《热力透平》2008,37(2):128-132
随着大容量直接空冷机组陆续投产运行,空冷机组真空系统在生产运行中所暴露出的问题逐渐显现.本文针对大型直接空冷机组真空系统特点、真空泄漏、真空严密性等方面做了分析探讨,为今后直接空冷机组安全、稳定、经济运行提供必要的参考依据.  相似文献   

6.
针对近年来投产的空冷机组在启动和运行方面出现的问题,搭建了空冷系统试验台,模拟空冷机组运行,针对空冷机组运行的特点作出相应的改进和优化,并对散热器优化提出建议,为我国大容量空冷机组提供借鉴.  相似文献   

7.
针对某核电汽轮发电机组振动保护存在的问题,通过调研国内核电机组振动保护设置情况,分析国内振动保护设置的几种典型情况,得出汽轮发电机组采用轴振组合逻辑的合理性,并对汽轮发电机组振动延时问题进行了探讨,给出了建议,有效解决了问题。研究成果可为同类机组的振动保护设置提供参考。  相似文献   

8.
一、空冷机组的特点 空冷发电机组是节水非常显著的发电方式,目前采用循环冷却系统的大型湿冷火电机组水耗指标约为0.65m^3/(S.GW),而采用大型空冷机组的水耗指标约为0.13m^3/(S.GW),对同容量的机组来说,空冷机组的耗水量可减少到湿冷机组的20%,因此,在我国“三北”富煤贫水地区,大力开发大型空冷机组,对节约宝贵的水资源和电力工业可持续发展具有重大的战略意义。  相似文献   

9.
我国火电空冷技术的发展概况及特点   总被引:3,自引:0,他引:3  
王佩璋 《热力透平》2006,35(4):224-228
为了在我国富煤缺水地区推广应用节水型火电空冷机组,简介了现有空冷机组概况和发展前景,阐述了我国火电直接空冷注重环保采取降噪措施,按我国国情固有的特点而形成的空冷总体特点和系统特点,证明我国火电空冷具有广阔的市场前景。  相似文献   

10.
结合新疆某空冷机组工程的具体情况,讨论空冷发电机组给水泵的选择方案,着重分析了300 MW空冷机组三台35%与50%电动调速给水泵配置的经济性比较,并提出了推荐方案。  相似文献   

11.
Woody biomass in Finland and Sweden comprises mainly four wood species: spruce, pine, birch and aspen. To study the ash, which may cause problems for the combustion device, one tree of each species were cut down and prepared for comparisons with fuel samples. Well-defined samples of wood, bark and foliage were analyzed on 11 ash-forming elements: Si, Al, Fe, Ca, Mg, Mn, Na, K, P, S and Cl. The ash content in the wood tissues (0.2–0.7%) was low compared to the ash content in the bark tissues (1.9–6.4%) and the foliage (2.4–7.7%). The woods’ content of ash-forming elements was consequently low; the highest contents were of Ca (410–1340 ppm) and K (200–1310), followed by Mg (70–290), Mn (15–240) and P (0–350). Present in the wood was also Si (50–190), S (50–200) and Cl (30–110). The bark tissues showed much higher element contents; Ca (4800–19,100 ppm) and K (1600–6400) were the dominating elements, followed by Mg (210–2400), P (210–1200), Mn (110–1100) and S (310–750), but the Cl contents (40–330) were only moderately higher in the bark than in the wood. The young foliage (shoots and deciduous leaves) had the highest K (7100–25,000 ppm), P (1600–5300) and S (1100–2600) contents of all tissues, while the shoots of spruce had the highest Cl contents (820–1360) and its needles the highest Si content (5000–11,300). This paper presented a new approach in fuel characterization: the method excludes the presence of impurities, and focus on different categories of plant tissues. This made it possible to discuss the contents of ash element in a wide spectrum of fuel-types, which are of large importance for the energy production in Finland and Sweden.  相似文献   

12.
正1 ABSTRACT To reduce the effect of global warming on our climate,the levels of CO2emissions should be reduced.One way to do this is to increase the efficiency of electricity production from fossil fuels.This will in turn reduce the amount of CO2emissions for a given power output.Using US practice for efficiency calculations,then a move from a typical US plant running at 37%efficiency to a 760℃/38.5 MPa(1 400/5 580 psi)plant running at 48%efficiency would reduce CO2emissions by 170kg/MW.hr or 25%.  相似文献   

13.
The purpose of this paper is to illustrate the advantages of the direct surface-curvature distribution blade-design method, originally proposed by Korakianitis, for the leading-edge design of turbine blades, and by extension for other types of airfoil shapes. The leading edge shape is critical in the blade design process, and it is quite difficult to completely control with inverse, semi-inverse or other direct-design methods. The blade-design method is briefly reviewed, and then the effort is concentrated on smoothly blending the leading edge shape (circle or ellipse, etc.) with the main part of the blade surface, in a manner that avoids leading-edge flow-disturbance and flow-separation regions. Specifically in the leading edge region we return to the second-order (parabolic) construction line coupled with a revised smoothing equation between the leading-edge shape and the main part of the blade. The Hodson–Dominy blade has been used as an example to show the ability of this blade-design method to remove leading-edge separation bubbles in gas turbine blades and other airfoil shapes that have very sharp changes in curvature near the leading edge. An additional gas turbine blade example has been used to illustrate the ability of this method to design leading edge shapes that avoid leading-edge separation bubbles at off-design conditions. This gas turbine blade example has inlet flow angle 0°, outlet flow angle −64.3°, and tangential lift coefficient 1.045, in a region of parameters where the leading edge shape is critical for the overall blade performance. Computed results at incidences of −10°,   −5°,   +5°,   +10° are used to illustrate the complete removal of leading edge flow-disturbance regions, thus minimizing the possibility of leading-edge separation bubbles, while concurrently minimizing the stagnation pressure drop from inlet to outlet. These results using two difficult example cases of leading edge geometries illustrate the superiority and utility of this blade-design method when compared with other direct or inverse blade-design methods.  相似文献   

14.
A chemical reactor for the steam-gasification of carbonaceous particles (e.g. coal, coke) is considered for using concentrated solar radiation as the energy source of high-temperature process heat. A two-phase reactor model that couples radiative, convective, and conductive heat transfer to the chemical kinetics is applied to optimize the reactor geometrical configuration and operational parameters (feedstock's initial particle size, feeding rates, and solar power input) for maximum reaction extent and solar-to-chemical energy conversion efficiency of a 5 kW prototype reactor and its scale-up to 300 kW. For the 300 kW reactor, complete reaction extent is predicted for an initial feedstock particle size up to 35 μm at residence times of less than 10 s and peak temperatures of 1818 K, yielding high-quality syngas with a calorific content that has been solar-upgraded by 19% over that of the petcoke gasified.  相似文献   

15.
16.
汽轮机数字电液调节系统挂闸异常的技术完善   总被引:1,自引:0,他引:1  
分析了200MW汽轮机数字电液调节系统在运行中存在的挂闸异常问题,采取了相应的技术处理措施,且运行实践效果良好。  相似文献   

17.
为了提高喷油器电磁阀的响应速率,提出了一种基于CPLD(复杂可编程逻辑器件)应用于高压共轨ECU的数字升压模块。鉴于该升压电路结构参数多,其升压电压的恢复响应要求高等特征,基于Pspice建立了升压电路的仿真模型,研究了不同电路参数下升压模块的输出特性,全面优化了该升压模块的性能。结果显示,该升压模块的最大转换效率可以达90%以上。在柴油发动机上对ECU的试验表明,升压电压最大波动不超过10%,其恢复时间仅为1.3ms,功率管最大温升仅为41℃,满足整机运行范围内ECU的需求。  相似文献   

18.
The physical aspects of the activation energy, in higher and high temperatures, of the metal creep process were examined. The research results of creep-rupture in a uniaxial stress state and the criterion of creep-rupture in biaxial stress states, at two temperatures, are then presented. For these studies creep-rupture, taking case iron as an example the energy and pseudoenergy activation was determined. For complex stress states the criterion of creep-rupture was taken to be Sdobyrev's, i.e. σred = σ1 β + (1 − β)σi, where: σ1-maximal principal stress, σi-stress intensity, β-material constant (at variable temperature β = β(T)). The methods of assessment of the material ageing grade are given in percentages of ageing of new material in the following mechanical properties: 1) creep strength in uniaxial stress state, 2) activation energy in uniaxial stress state, 3) criterion creep strength in complex stress states, 4) activation pseudoenergy in complex stress states. The methods 1) and 3) are the relatively simplest because they result from experimental investigations only at nominal temperature of the structure work, however, for methods 2) and 4) it is necessary to perform the experimental investigations at least at two temperatures.  相似文献   

19.
Hydrogen was produced from primary sewage biosolids via mesophilic anaerobic fermentation in a continuously fed bioreactor. Prior to fermentation the sewage biosolids were heated to 70 °C for 1 h to inactivate methanogens and during fermentation a cellulose degrading enzyme was added to improve substrate availability. Hydraulic retention times (HRT) of 18, 24, 36 and 48 h were evaluated for the duration of hydrogen production. Without sparging a hydraulic retention time of 24 h resulted in the longest period of hydrogen production (3 days), during which a hydrogen yield of 21.9 L H2 kg−1 VS added to the bioreactor was achieved. Methods of preventing the decline of hydrogen production during continuous fermentation were evaluated. Of the techniques evaluated using nitrogen gas to sparge the bioreactor contents proved to be more effective than flushing just the headspace of the bioreactor. Sparging at 0.06 L L min−1 successfully prevented a decline in hydrogen production and resulted in a yield of 27.0  L H2 kg−1 VS added, over a period of greater than 12 days or 12 HRT. The use of sparging also delayed the build up of acetic acid in the bioreactor, suggesting that it serves to inhibit homoacetogenesis and thus maintain hydrogen production.  相似文献   

20.
As part of a pilot study investigating the role of microorganisms in the immobilisation of As, Sb, B, Tl and Hg, the inorganic geochemistry of seven different active sinter deposits and their contact fluids were characterised. A comprehensive series of sequential extractions for a suite of trace elements was carried out on siliceous sinter and a mixed silica-carbonate sinter. The extractions showed whether metals were loosely exchangeable or bound to carbonate, oxide, organic or crystalline fractions. Hyperthermophilic microbial communities associated with sinters deposited from high temperature (92–94°C) fluids at a variety of geothermal sources were investigated using SEM. The rapidity and style of silicification of the hyperthermophiles can be correlated with the dissolved silica content of the fluid. Although high concentrations of Hg and Tl were found associated with the organic fraction of the sinters, there was no evidence to suggest that any of the heavy metals were associated preferentially with the hyperthermophiles at the high temperature (92–94°C) ends of the terrestrial thermal spring ecosystems studied.  相似文献   

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