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电站锅炉火焰检测及燃烧诊断技术 总被引:19,自引:0,他引:19
电站锅炉的安全运行主要决定于燃烧的稳定性,实时探测燃烧火焰是否稳定,及时作出判断,对电站锅炉安全运行有着重要的实际意义。本文分析了炉膛火焰特征与火焰检测和燃烧诊断的关系,论述了火焰检测的基本原理和方法以及燃烧诊断理论和技术,并对目前火电厂燃煤锅炉应用的各种火焰检测器和燃烧诊断系统进行了分析比较,最后讨论了火焰检测及燃烧诊断技术的进一步研究方向。 相似文献
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基于频谱分析和自组织神经网络的火焰燃烧诊断研究 总被引:14,自引:1,他引:14
通过对实验室煤粉燃烧炉实验数据的采集与分析,介绍了一种基于FFT变换处理与自组织神经网络状态识别相结合的燃烧诊断方法。首先,通过光电传感器获得一系列以一定的频率、在某个均值左右上下波动的火焰强度值。然后,利用FFT程序将获得的时域信号转换成频域上的功率谱信号。因为在稳定和不稳定的燃烧状态下,转换后得到的低频分量有明显的区别,所以把每个功率谱中前30个低频分量取出,将其作为神经网络的训练输入。通过自组织训练,神经网络将得到对应于稳定和不稳定燃烧状态火焰信号的不同输出区域。经过验证,这种方法能非常有效地识别燃烧火焰状态的稳定与否,在信号采样频率的选择,神经网络算法的改进等方面作了有意义的探索。图4表3参12 相似文献
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基于神经网络的零维预测燃烧模型及建模方法 总被引:1,自引:0,他引:1
《内燃机学报》2015,(2)
提出了基于神经网络的零维预测燃烧模型,适用于发动机稳态和动态过程的燃烧计算.以建立高原增压柴油机燃烧模型为例,介绍了基于神经网络的零维预测燃烧模型的建模步骤,主要包括放热率计算、放热率参数化、构建和训练神经网络.介绍了缸压处理和放热率计算方法;以三韦伯函数形式拟合放热率曲线,增加一系列约束解决拟合参数的多解问题;构建并训练了神经网络,完成建模.通过训练误差分析、预测结果与试验数据的对比,对模型的预测精度进行了验证. 相似文献
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基于火焰序列图像的煤粉燃烧稳定性判别 总被引:10,自引:1,他引:9
研究煤粉燃烧稳定性判别问题。对煤粉火焰图像进行了分析,提出了差分图像相对变化量作为特征参数来表征燃烧稳定性的方法,在此基础上提出了一种燃烧稳定性模糊判别方法。该方法将燃烧稳定性知识用语言形式描述出来,通过建立语言与特征参数之间的模糊关系,进而建立了特征参数与燃烧稳定性之间的模糊模式关系。试验表明:判别方法能有效地进行燃烧稳定性判别。这对实现燃烧状态自动监测,保障锅炉安全运行具有实际意义。图5参4 相似文献
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本文介绍了一种利用工业孔探仪对发动机内部损伤进行检测和识别的新方法。通过孔探探头采集发动机内部损伤图像,利用数字图像处理中的最大类间方差法分割出损伤区域,提取损伤图像的几何特征和纹理特征,并将提取的图像特征输入神经网络进行分层识别,最后由专家系统对损伤程度进行诊断。系统实现了孔探检测损伤的自动分类和损伤程度的自动诊断。通过现场测试,证明了该方法的有效性和实用性。 相似文献
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Ali Mirsephai Morteza Mohammadzaheri Lei Chen Brian O'Neill 《International Communications in Heat and Mass Transfer》2012
In this work, a new solution approach was developed for heat estimation class of inverse heat transfer problems where radiation provides the dominant mode thermal energy transport. An Artificial Neural Network (ANN) was designed, trained and employed to estimate the heat emitted to irradiative batch drying process. 相似文献
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《International Journal of Heat and Mass Transfer》2007,50(11-12):2089-2100
This paper presents an efficient technique for analyzing inverse heat conduction problems using a Kalman Filter-enhanced Bayesian Back Propagation Neural Network (KF-B2PNN). The training data required for the KF-B2PNN are prepared using the Continuous-time analogue Hopfield Neural Network and the performance of the KF-B2PNN scheme is then examined in a series of numerical simulations. The results show that the proposed method can predict the unknown parameters in the current inverse problems with an acceptable error. The performance of the KF-B2PNN scheme is shown to be better than that of a stand-alone Back Propagation Neural Network trained using the Levenberg–Marquardt algorithm. 相似文献
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Asghar Alizadehdakhel Masoud Rahimi Jafar Sanjari Ammar Abdulaziz Alsairafi 《International Communications in Heat and Mass Transfer》2009,36(8):850-856
A large number of experiments in a 2 cm diameter and 6 m length tube were carried out in order to study the two-phase flow regimes and pressure drops in it. The two-phase flow in the experimental tube was modeled using commercial CFD code, Fluent 6.2. An Artificial Neural Network (ANN) with three inputs including gas and liquid velocities and tube slope was designed and trained to predict average pressure drop across the tube. The comparison between CFD and ANN predictions of pressure drops with experimental measurements shows that the CFD results are more accurate than the ANN evaluations for new conditions. 相似文献
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由于电力市场竞争的日益激烈,电力企业纷纷采用先进的控制策略和手段来加强市场竞争力。因此,将模糊逻辑、神经网络等智能技术与基于模型的控制技术引入过程控制领域,形成先进过程优化控制的研究得到广泛关注。本文介绍了一种蒸汽温度优化控制系统在火电厂中的应用,设计了两种动态的优化过程,分别基于模糊控制和神经网络,并通过测试验证了该方案的应用,可明显有效地提高电厂运行效率,控制汽温范围,具有较强的现实意义。 相似文献
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叙述了基于T-S模型的模糊神经网络应用于三川河地表水质的评价,且说明用单因子评价法和综合指数评价法能取得了较好的效果,为水质评价提供了新的方法. 相似文献
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Artificial Neural Networks (ANN) are multifaceted tools that can be used to model and predict various complex and highly non-linear processes. This paper presents the development and validation of an ANN model of a CO2 capture plant. An evaluation of the concept is made of the usefulness of the ANN model as well as a discussion of its feasibility for further integration into a conventional heat and mass balance programme. It is shown that the trained ANN model can reproduce the results of a rigorous process simulator in fraction of the simulation time. A multilayer feed-forward form of Artificial Neural Network was used to capture and model the non-linear relationship between inputs and outputs of the CO2 capture process. The data used for training and validation of the ANN were obtained using the process simulator CO2SIM. The ANN model was trained by performing fully automatic batch simulations using CO2SIM over the entire range of actual operation for an amine based absorption plant. The trained model was then used for finding the optimum operation for the example plant with respect to lowest possible specific steam duty and maximum CO2 capture rate. Two different algorithms have been used and compared for the training of the ANN and a sensitivity analysis was carried out to find the minimum number of input parameters needed while maintaining sufficient accuracy of the model. The reproducibility shows error less than 0.2% for the closed loop absorber/desorber plant. The results of this study show that trained ANN models are very useful for fast simulation of complex steady state process with high reproducibility of the rigorous model. 相似文献