共查询到18条相似文献,搜索用时 156 毫秒
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基于模糊神经网络的电站燃煤锅炉结渣预测 总被引:7,自引:0,他引:7
综合运用模糊数学和神经网络知识构建了一个模糊神经网络模型,用以预测电站燃煤锅炉的结渣特性.通过引入反映煤灰特性的4个常用指标以及反映锅炉运行情况的两个指标,使所建模型综合考虑了煤灰特性和锅炉运行因素对结渣的影响.以实际电厂燃煤锅炉为样本,基于改进的BP(back-propagation)算法对网络模型进行了训练.为验证模型的准确性,对7台电站燃煤锅炉的结渣特性进行预测,并将该模型与只考虑煤灰特性指标的常规 BP网络模型进行比较.验证结果表明,模糊神经网络模型的预测结果与实际相符,效果优于常规BP网络模型. 相似文献
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应用支持向量机算法对燃煤锅炉结渣问题进行数学建模,并利用模拟退火算法对支持向量机模型参数进行了优化,最终获得最优参数组合。模型将煤的软化温度tSt、硅铝比w(SiO2)/w(A12O3)、碱酸比J和硅比G以及锅炉的无因次切圆直径t和无因次实际切圆直径d作为输入变量,以结渣程度作为输出,用试验数据对模型进行了校验和参数的寻优,利用优化后的模型对15台锅炉结渣特性进行预测评判,有14个正确,评判准确率为93.33%,由此表明此方法是合理有效的。同时为了配合该模型,采用高级语言编程开发出了相应的预测评判系统。 相似文献
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电站燃煤结渣特性的模糊模式识别 总被引:1,自引:1,他引:1
目前国内外普遍采用的单一煤灰结渣特性指标分辨率较低,有时甚至出现按某一准则判别的结果与实际结渣程度相矛盾的情况。本文运用模糊数学的方法对电站燃煤的结渣特性进行了模式识别,用以综合判定燃煤的结渣性能,可作为锅炉运行和设计部门预测炉内结渣程度的依据。 相似文献
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模糊综合评判模型预测电站燃煤结渣特性的研究 总被引:2,自引:0,他引:2
基于最大隶属度原则,采用常规煤质结渣特性指标以及炉膛运行参数组成的"6指标法"对模糊理论预测燃煤结渣的4种常用模型进行了分析和检验.分析发现,4种模型都具有较好的预测效果,但相比而言,具有"主因素决定型"特征的模型由于过于强调单一指标的作用效果,在评判过程中容易陷于局部最大修正隶属度的误区,从而导致对结渣倾向性不明显样本预测的失效.考虑各因素影响的综合评判方法则避开了这一误区,在整体预测效果上获得了更高的准确度. 相似文献
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Md Tanvir ALAM Baiqian DAI Xiaojiang WU Andrew HOADLEY Lian ZHANG 《Frontiers in Energy》2021,15(1):46
Gasification or combustion of coal and biomass is the most important form of power generation today. However, the use of coal/biomass at high temperatures has an inherent problem related to the ash generated. The formation of ash leads to a problematic phenomenon called slagging. Slagging is the accumulation of molten ash on the walls of the furnace, gasifier, or boiler and is detrimental as it reduces the heat transfer rate, and the combustion/gasification rate of unburnt carbon, causes mechanical failure, high-temperature corrosion and on occasions, superheater explosions. To improve the gasifier/combustor facility, it is very important to understand the key ash properties, slag characteristics, viscosity and critical viscosity temperature. This paper reviews the content, compositions, and melting characteristics of ashes in differently ranked coal and biomass, and discusses the formation mechanism, characteristics, and structure of slag. In particular, this paper focuses on low-rank coal and biomass that have been receiving increased attention recently. Besides, it reviews the available methodologies and formulae for slag viscosity measurement/prediction and summarizes the current limitations and potential applications. Moreover, it discusses the slagging behavior of different ranks of coal and biomass by examining the applicability of the current viscosity measurement methods to these fuels, and the viscosity prediction models and factors that affect the slag viscosity. This review shows that the existing viscosity models and slagging indices can only satisfactorily predict the viscosity and slagging propensity of high-rank coals but cannot predict the slagging propensity and slag viscosity of low-rank coal, and especially biomass ashes, even if they are limited to a particular composition only. Thus, there is a critical need for the development of an index, or a model or even a measurement method, which can predict/measure the slagging propensity and slag viscosity correctly for all low-rank coal and biomass ashes. 相似文献
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为提高基于模糊神经网络的锅炉炉膛受热面结渣预测精度,提出了一种基于广义钟型隶属度函数非线性惯性权重递减调整策略的粒子群优化算法,通过适应度测试函数对比实验、结渣预测实验和预测稳定性分析对现有文献中线性惯性权重递减调整策略(LPSO)、指数型非线性惯性权重递减调整策略(IPSO)和基于广义钟型隶属度函数非线性惯性权重递减调整策略(GJPSO)进行对比分析。研究结果表明:本文所改进的粒子群算法可以有效地改善算法的早熟现象、平衡算法的全局和局部搜索能力、提高算法的收敛效果和稳定性。利用改进后的粒子群算法对模糊神经网络中的权值和阈值进行优化,提高了模糊神经网络的炉膛结渣预测性能。 相似文献
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