基于EMD降噪的燃烧器火焰静电信号能量熵分析

Energy entropy analysis of flame signals obtained by an electrostatic sensor array based on EMD denoising method

采用灵敏度高、结构简单、环境适应性强的非侵入式静电传感器阵列测量甲烷及生物质火焰的能量变化特性。基于经验模态分解的降噪方法对测量信号进行去噪处理,以获得信号的能量熵用于表征火焰中带电颗粒运动复杂度。实验中对甲烷-空气预混和扩散火焰以及甲烷助燃生物质火焰进行测量。研究结果表明:甲烷扩散火焰带电颗粒运动复杂度随燃料流量的增大而增大,相同甲烷流量下,空气流量越大预混火焰颗粒运动复杂度越高,生物质火焰中带电颗粒运动复杂度比气态甲烷火焰的高,火焰中部带电颗粒运动复杂度最高。

A non-invasive electrostatic sensor array with high sensitivity,simple structure and good environmental adaptability was used to measure the energy characteristics of burner flames in different combustion tests.A denoising method based on empirical mode decomposition(EMD)was adopted to denoise the original sensor signals before calculating the EMD energy entropy of the flame,which was used to evaluate the motion complexity of charged particles in a flame.Experimental tests were conducted under various flame conditions,such as methane-air diffusion flames,methane-air premixed flames and methane-assisted biomass flames.The results show that the motion complexity of charged particles in diffusion and premixed flames increases with the flow rate of methane.The motion complexity of charged particles in biomass flames is higher than that of methane flames.The motion complexity of charged particles in the middle region of a flame is the highest.