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对于S-CO2燃煤发电系统,系统复杂难以横向比较,拆分法通过对循环流量分配,能够梳理循环回热过程并进行循环间的比较,应用循环拆分法有助于对复杂燃煤发电系统的性能进行分析。本文以再压缩循环(RC)为例,构建了集成冷却器热量回收(CHR)和烟气冷却器法(FGC)的S-CO2燃煤发电系统(RC+LFGC+CHR),论证了拆分法在分析燃煤发电系统中的优势。当主气参数为620?C/28 MPa时,应用拆分法分析,RC+FGC+CHR可等效为在热效率49.21%的RC基础上,叠加热效率为57.49%的子循环(SSC+LFGC+CHR),故RC+FGC+CHR效率(49.80%)高于RC(49.21%)。 相似文献
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理论和实践证明,各种联合循环均存在有使循环热效率达最高值的热力特性参数最优化组合.寻求这样的最优化组合是十分重要的. 一、最优化数学模型 由热力学知,联合循环发电装置的热效率η是与燃气循环参数及系统、蒸汽循环参数及系统、燃料特性、各组成元件的内效率及压力保持系数、联合循环的型式、燃机与汽机功率比等诸因素有关的多元函数,很难求得解析表达式.本文选取次要影响因素为确定值, 相似文献
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排气全燃型联合循环设计点性能简明估计公式 总被引:1,自引:0,他引:1
排气全燃型联合循环设计点性能简明估计公式蔡睿贤(中国科学院工程热物理研究所北京10O080)关键词:排气全燃型联合循环,热力分析主要符号表Hu燃料热值L燃料理论空气量l比功P单位能量价格R燃气轮机与蒸汽轮机的功率比α过量空气系数β摩尔燃料系数△增量η... 相似文献
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用于IGCC的燃气轮机技术方案与性能预测 总被引:4,自引:2,他引:2
主要符号表T温度G质量流量。压气机压比。压气机进口导叶安装角N功率X。压损系数X。。氮气回注系数X。;,空分整体化系数下标a空气cg煤气0烧天然气时设计工况。氮气as空分装置f燃料O。氧气1Bu8整体煤气化联合循环(IGCC)燃气轮机与常规的燃机有很大的差异[“l。它改烧中低热值的合成煤气,其燃料量比烧高热值的油气时要增大几倍;不同空分方案和采用不同的NZ回注掺混量时,情况就更为复杂。透平工质流量比压气机空气流量相差很多,燃气轮机总是处于复杂的变工况状态。2IGCC中燃气轮机技术方案归纳IGCC中燃气轮机可行的技术方案… 相似文献
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联合循环中蒸汽底循环系统稳态全工况特性模型及计算分析 总被引:12,自引:0,他引:12
主要符号表GI质流量US换热能力系数d水、蒸汽侧参数h比烩值。对流换热系数g烟气侧参数k换热系数p。HRSG传热效率h高压段参数NP底循环压力级数西几对数平均温差l低压段参数Q换热器热交换量下标:如人口参数S换热面积0基准点参数O。t出日参数1Bua随着燃气轮机性能参数逐年提高,排气温度也相应升高,需要更有效地回收排气余热、因此,优化设计蒸汽底循环,对其进行较准确的全工况性能计算分析愈显重要。已有对联合循环中蒸汽底循环的分析或多或少存在着一些局限性。最普遍的局限性是,对底循环系统匹配和构成方式研究不深人或不全面,多… 相似文献
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IGCC空气侧整体综合优化的研究 总被引:4,自引:1,他引:3
主要符号表X。。氮气回注系数如空分整体化系数E。;c燃气轮机压气机效率G。l回注氮气流量万燃气轮机透平前温尼。”系统相对效率G。。煤气氮气掺混流量Ea;,c空气专用压缩机效率N。”系统相对功率1前言整体煤气化联合循环(IGCC)系统模拟与优化逐步受到重视,开展了许多相关研究[‘-‘]。但是,现有的方法[‘,‘]一个突出的问题,它是在设定的具体流程方案下的数值分析,这常常导致落入“局部优化掩盖了整体最优”的误区。本文是研究以空分系统为中心的空气侧子系统的整体优化,阐述基本概念,尝试新方法,并结合大型商业化装… 相似文献
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固体氧化物燃料电池是将化学能转化成电能的全固态能量转换装置,被认为是极具前景的绿色发电系统。本研究提出了结合碳捕集的固体氧化物燃料电池-超临界二氧化碳布雷顿循环集成系统,通过阳极尾气富氧燃烧实现低能耗碳捕集,并利用s CO2再压缩布雷顿循环回收燃烧室余热提高系统效率。模拟结果显示,该集成系统在设计工况下的净发电效率为59.74%,二氧化碳捕集量为134.50 kg/h。此外,关键工作参数对系统性能的影响分析结果表明,合理的阳极尾气再循环比、燃料利用率和燃料流量是确保系统安全高效运行的必要前提。 相似文献
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Sham-Tsong Shiue 《Optical and Quantum Electronics》1996,28(10):1379-1394
Thermally induced microbending losses in initially curved tightly jacketed double-coated optical fibres at low temperature are investigated. The initial deflections are described by a more general formula. The deflections in an initially curved fibre increase gradually with increasing thermally induced compressive axial force, and result in an increase of microbending loss. In order to minimize such a microbending loss, the Young's modulus and Poisson's ratio of the primary coating should be increased. The best value of the Poisson's ratio of the primary coating is 0.5. On the other hand, the thickness of the primary coating, the Young's modulus and effective thermal expansion coefficient of the secondary coating, and the thickness, Young's modulus and effective thermal expansion coefficient of the jacket should be decreased. These results are compared to those of double-coated optical fibres. Thermally induced lateral pressure in the glass fibre can also produce microbending loss. When the effects of axial force and lateral pressure on the microbending losses are both considered, the optimum selection of polymeric coatings is to let the lateral pressure be less than zero, and the magnitude of lateral pressure and the ratio of the final-initial deflection be as small as possible. When the material properties of polymeric coatings and their thicknesses are selected, there are two ways to achieve the optimum design. 相似文献
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Fibers of fully aromatic thermotropic liquid-crystal polymers containing mesogenic groups in the backbone are prepared on
laboratory machines that make it possible to vary the conditions of jet spinning and subsequent heat treatment. The thermal
and mechanical properties of the polymer fibers are investigated using differential thermal and thermomechanical analyses
and strength measurements. It is found that, after spinning under optimum conditions, the strength of the fibers at room temperature
is approximately equal to 1 GPa. After heat treatment under specially chosen conditions, the strength increases by a factor
of two or three due to an increase in the activation energy of fracture. The role of crystallization and cross-linking in
strengthening of liquid-crystal polymer fibers is elucidated. 相似文献
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A test bed for development of catalysts in a temperature programmed reactor is described. The effluent species are monitored
in real time. Such data are collected into spreadsheet arrays which can be interrogated to yield kinetic data. An appropriate
reactor design can therefore proceed directly from laboratory measurements to generate whole plant simulation analysis and
commercial evaluation. For the oxidative coupling of methane, the hydrocarbon to oxygen ratio in the feed is of particular
importance since the state of oxidation plays a significant role in determining the selectivity of the catalyst to the optimum
product distribution. Homogeneous gas phase reactions may also occur at high temperatures, hence the reactor volume both upstream
and downstream of the catalyst must also be considered.
The stability of the catalyst under reactor conditions can be further assessed by following temperature programmed, thermal
gravimetric and differential thermal analyses in diverse oxidizing, reducing or reaction atmospheres. Temperature programmed
AC electrical measurements also give further insight into changes in the catalyst both at the surface and in the bulk as chemical
reactions proceed. Examples of these techniques on a variety of mixed oxides such as Li-Ni-Co-O, La-Sr-Co-Fe-O and K-β′' alumina
are presented.
Paper presented at the 4th Euroconference on Solid State Ionics, Renvyle, Galway, Ireland 相似文献
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光纤热极化过程的实时测试研究 总被引:1,自引:0,他引:1
通过热极化可以使中心对称的熔石英光纤中产生二阶非线性效应和线性电光效应。为了解各热极化过程参量对热极化产生的线性电光效应的影响,利用全保偏光纤马赫一曾德尔干涉仪构造了一套光纤热极化的实时线性电光效应测试系统,并利用其进行了光纤热极化全过程的监控测试。在线测试了热极化过程的一些参量,例如极化电压、极化时间、以及极化温度等对热极化光纤中产生的线性电光效应的影响。实时测试研究表明,在光纤中施加尽可能高的极化电场将可能在光纤中产生较高的线性电光效应。对侧边抛磨光纤结构的热极化器件,考虑到器件的抗强电场击穿能力,可选用3.o~4.0kV左右的极化直流电压。当施加3.0kV左右的极化电压时,热极化优化时间约为16min,最佳热极化加热温度约为190℃。 相似文献
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针对异面腔四频差动激光陀螺(DILAG)工作模式不确定性和跳模对其性能的负面影响,提出了根据开机时腔体温度快速选择最优初始模的智能选模方法。分析了纵模阶数对DILAG的零偏和比例因子的影响以及跳模的危害,指出选择最优初始模是在现有基础上进一步提高DILAG性能的重要方法。通过温度实验做出了最优模相应的压电换能器(PZT)驱动电压随温度的变化曲线,为建立选模模型提供了基本依据。实验表明,智能选模使腔长控制系统加电后能快速稳定在最优初始模,减小了跳模几率,提高了腔长控制电路的鲁棒性和自适应性,对改善DILAG的性能、可靠性具有实用价值。 相似文献
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At least two bunchers are needed in the 3MeV H- Medium Energy Beam Transport (MEBT) line located between RFQ and DTL for the CSNS (China Spallation Neutron Source). A nose-cone geometry has been adopted as the type of buncher cavity for its simplicity, higher impedance and lower risk of multipacting. By making use of the results got from the simulations on the buncher with two-dimension code SUPERFISH, the thermal and structural analyses have been carried out, the process and results to determine the resulting frequency shift due to thermal and structural distortion of the cavity are presented, the water-cooling channel position and the optimum cooling water temperature as well as the tuning method by adjusting the cooling water temperature when the cavity is out of resonance are also determined through the analyses. 相似文献
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激光测距仪信噪比与激光发散角最佳值的选取 总被引:2,自引:0,他引:2
研讨激光测距仪的信噪比和激光发散角如何选取最佳值的问题。如果信噪比为SNR,激光发散角为θt,则取SNR θt^2最小时的信噪比和激光发散角为最佳值。 相似文献