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加热器端差对机组经济性的影响 总被引:3,自引:1,他引:3
汽轮机热力系统中的加热器的运行情况对机组经济性有较大的影响,采用等效焓降法定量分析ANSALD TCDF-33.5型机组加热器端差对机组经济性的影响。结果表明,如果加热器端差从运行的实际值减少至设计值,机组经济性明显提高。这项工作对指导回热系统运行及研究机组经济性具有重要意义。 相似文献
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准确而快速地评价加热器端差引起的机组热经济性变化,对热力系统的设计、运行和检修具有十分重要的意义.以热力系统热平衡方程、锅炉输入燃料(火用)方程、锅炉吸热量方程、汽轮机输入热(火用)量(火用)方程和汽轮机功率方程为基础,根据小扰动理论和微分理论,得各抽汽量、锅炉输入燃料炯、锅炉吸热量、汽轮机输入热量(火用)和汽轮机功率对端差的变化率.在锅炉(火用)效率、机组炯效率和发电煤耗率概念的基础上,由微分理论推导端差对(火用)经济性指标的影响.以N 1000 - 25/600/600机组为例,计算加热器端差对机组(火用)经济性指标的影响. 相似文献
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高压加热器的运行对机组的热经济性具有重要影响.以300 MW凝汽式机组的热力系统为例,结合高加的端差、抽汽压力损失和散热损失3个方面,得出了高加运行与机组热经济性的具体关系和影响机组热经济性的强度系数,并绘制出了强度系数、得出煤耗率与机组负荷的关系曲线.得到了机组的运行中需要重点监测的参数和系统的改造方案,为机组的最优运行和改造工作提供了理论基础. 相似文献
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回热级数是影响机组热经济性的重要因素,级数变化引起的给水温度的变化,对机组热经济性也有重要影响。定性分析了回热级数及给水温度变化对机组热经济性的影响,并以某1000MW机组为例,定量分析了该机组在不同负荷工况下增设0号高压加热器后的热经济性,分析得出机组热经济性随给水温度的升高先升高后降低,即存在最佳给水温度,进而确定了0号高压加热器最佳进汽压力,与未增设0号高加时经济性相对比,增设0号高压加热器能显著提高机组在低负荷运行下的热经济性,且负荷越低经济性提高越明显。 相似文献
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基于热力系统矩阵方程理论,针时不同型式的加热器,推导出了加热器端盖对机组功率增量及吸热量增量的计算公式,并建立了N300-16.7/537/537机组各级加热器端盖对循环效率影响的数学模型。经实例计算表明:该模型具有结果准确、使用简便、通用性强等优点,尤其适用于机组运行经济性在线监测系统。 相似文献
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定量计算分析加热器上端差变化对火电机组发电煤耗率的影响对节能降耗具有重要的现实意义,为解决以前计算方法的局限性,提出了一种计算上端差改变对煤耗率影响的新方法.以火电机组热经济性分析的统一物理模型和数学模型为基础,借助梯度算子,建立了基于强度矩阵的上端差改变对煤耗率影响的通用计算模型,并对某600MW机组的典型工况进行了计算.结果表明:该模型推导简单、计算量小、精度高且通用性强;强度矩阵可直接用于定性和定量地分析各个加热器上端差改变对机组煤耗率的影响;端差对经济性的影响除了其本身的大小外,还与加热器所处的位置和结构有关,在运行或检修中,更应关注强度系数大的加热器端差变化对经济性的影响. 相似文献
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A study is reported of the potential performance of dry cooling on power generation. This is done in the context of a generic trough solar thermal power plant. The commercial power plant analysis code GateCycle is applied for this purpose. This code is used to estimate typical performance of both wet and dry cooling options. Then it is configured to estimate the performance of ideal wet and dry cooling options. The latter are defined as the condenser temperature being at the ambient wet bulb temperature or dry bulb temperature, respectively. Yearly power production of a solar power plant located in Las Vegas is presented for each of the cooling options. To move further toward approaching the possible improvement in dry cooling, the impact of a high-performance heat exchanger surface is evaluated. It is found that higher efficiency generation compared to current dry cooling designs is definitely possible. In fact the performance of these types of systems can approach that of wet cooling system units. 相似文献
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Ana M. Blanco-Marigorta M. Victoria Sanchez-Henríquez Juan A. Peña-Quintana 《Energy》2011,36(4):1966-1972
Exergetic analysis is without any doubt a powerful tool for developing, evaluating and improving an energy conversion system. In the present paper, two different cooling technologies for the power cycle of a 50 MWe solar thermal power plant are compared from the exergetic viewpoint. The Rankine cycle design is a conventional, single reheat design with five closed and one open extraction feedwater heaters. The software package GateCycle is used for the thermodynamic simulation of the Rankine cycle model. The first design configuration uses a cooling tower while the second configuration uses an air cooled condenser. With this exergy analysis we identify the location, magnitude and the sources or thermodynamic inefficiencies in this thermal system. This information is very useful for improving the overall efficiency of the power system and for comparing the performance of both technologies. 相似文献
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50MW供热机组在线运行优化管理系统 总被引:1,自引:0,他引:1
结合供热机组运行的特点,采用热平衡法、循环函数法和等效焓降法,并辅以神经网络和模糊诊断等现代方法进行能损分析,首次将热工过程动态建模理论应用于供热机组的运行优化管理系统。介绍了某热电厂的运行优化管理系统的具体结构和功能实现,为供热机组的运行管理、节能降耗及提高经济效益提供了有力的指导依据。 相似文献
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In the present work, exergy analysis of a coal‐based thermal power plant is done using the design data from a 210 MW thermal power plant under operation in India. The entire plant cycle is split up into three zones for the analysis: (1) only the turbo‐generator with its inlets and outlets, (2) turbo‐generator, condenser, feed pumps and the regenerative heaters, (3) the entire cycle with boiler, turbo‐generator, condenser, feed pumps, regenerative heaters and the plant auxiliaries. It helps to find out the contributions of different parts of the plant towards exergy destruction. The exergy efficiency is calculated using the operating data from the plant at different conditions, viz. at different loads, different condenser pressures, with and without regenerative heaters and with different settings of the turbine governing. The load variation is studied with the data at 100, 75, 60 and 40% of full load. Effects of two different condenser pressures, i.e. 76 and 89 mmHg (abs.), are studied. Effect of regeneration on exergy efficiency is studied by successively removing the high pressure regenerative heaters out of operation. The turbine governing system has been kept at constant pressure and sliding pressure modes to study their effects. It is observed that the major source of irreversibility in the power cycle is the boiler, which contributes to an exergy destruction of the order of 60%. Part load operation increases the irreversibilities in the cycle and the effect is more pronounced with the reduction of the load. Increase in the condenser back pressure decreases the exergy efficiency. Successive withdrawal of the high pressure heaters show a gradual increment in the exergy efficiency for the control volume excluding the boiler, while a decrease in exergy efficiency when the whole plant including the boiler is considered. Keeping the main steam pressure before the turbine control valves in sliding mode improves the exergy efficiencies in case of part load operation. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献