基于数字图像处理的生物质混燃火焰稳定性检测方法  

Flame stability detection method for co-firing of biomass fuels based on digital image processing

作　　者：葛红[1] 徐伟程 闫勇[1,2] 卢钢[2] GE Hong;XU Weicheng;YAN Yong;LU Gang(School of Control and Computer Engmeering,North China Electric Power University Beijing 102206,China;School of Engineering and Digital Arts,University of Kent,Kent CT2 7NT,U.K.)

机构地区：[1]华北电力大学控制与计算机工程学院,北京102206 [2]肯特大学工程与数字艺术学院,英国坎特伯雷肯特CT2 7NT

出　　处：《热力发电》2019年第9期64-70,共7页Thermal Power Generation

基　　金：国家自然科学基金项目(51827808,61673170)~~

摘　　要：低质燃料或混合燃料(如煤粉+生物质等)的燃烧常常出现火焰不稳定现象,导致燃烧效率低、NOx排放量偏高等。由于燃烧器火焰本身的复杂性和现有检测方法的局限性,目前还无法对火焰的稳定性进行定量检测和评估。本文提出一种基于数字图像处理的生物质混燃火焰检测及稳定性评价方法。该方法定义了一个在[0,1]范围内连续取值的通用火焰稳定指数,并采用数字CCD相机采集火焰图像信息,通过图像分析提取火焰长度/高度、亮度、温度、闪烁频率等特征参数,经过对火焰特征参数进行统计分析和数据融合,求得火焰稳定指数,实现火焰稳定性的定量检测和评估。在生物质燃烧试验台对玉米芯、麦秸、柳木和花生壳4种不同生物质两两混合形成的3种混合生物质燃料进行了燃烧试验。试验结果表明定义的火焰稳定指数能够有效表征火焰燃烧状态。Combustion of low-quality fuels or fuel blends will lead to flame instability, resulting in low combustion efficiency and high NOx emissions. Due to the inherent complexity of burner flames and the lack of an effective means for flame monitoring and characterization, it is difficult to evaluate the flame stability in a combustion process quantitatively. To solve this problem, a method based on digital image processing for co-firing biomass fuels is proposed in this paper to monitor various characteristic parameters of a burner flame and evaluate its stability. In this method, a general flame stability index with continuous values in the range of [0, 1] is defined, and by using a digital CCD camera, the flame image information is collected. After the collected image is analyzed, the characteristic parameters like the flame length/height, brightness, temperature, flicker frequency and others are extracted. Then, statistical analysis and data fusion are carried out for theses characteristic parameters, and the flame stability index is obtained. Thus, the quantitative detection and evaluation of flame stability is realized. Moreover, this method was verified on a laboratory-scale combustion test rig. The combustion behaviours of different biomass blends(corncob-wheat straw blend, willow-peanut shell blend and peanut shell-wheat straw blend) were compared. The results show that, the defined flame stability index could effectively characterize the flame combustion state.

关 键 词：生物质 火焰 特征参数 火焰稳定性 火焰稳定指数 图像处理 数据融合 

分 类 号：TP391.7[自动化与计算机技术—计算机应用技术]