基于低采样率声波法的电站烟气流速测量  

Measurement of Flue Gas Velocity in Power Plant Based on Low Sampling Rate Acoustic Wave Method

作　　者：贺文凯 周宾[1] 任红伟 刘奇 岳晓庚 祝仰坤 向鹏 HE Wen-kai;ZHOU Bin;REN Hong-wei;LIU Qi;YUE Xiao-geng;ZHU Yang-kun;XIANG Peng(School of Energy and Environment,Southeast University,Nanjing 210096,China;QingHai Salt Lake Industry Co.Ltd,Golmud 816000,China)

机构地区：[1]东南大学能源与环境学院,江苏南京210096 [2]青海盐湖工业股份有限公司研发中心,青海格尔木816000

出　　处：《仪表技术与传感器》2020年第7期105-109,117,共6页Instrument Technique and Sensor

基　　金：国家重点研发计划项目(2017YFB0603204);国家自然科学基金项目(50976024);国家自然科学基金青年科学基金项目(50906013)。

摘　　要：为解决现有声学测速方法存在的计算量大且耗时长的问题,提出一种基于声学信号相关函数插值的电站脱硝出口烟气流速在线测量方法。研究了在较低采样率下对声学信号互相关函数进行插值处理,以获取准确的信号时延的可行性。数值仿真结果表明:采用三次样条插值方法得到的声波飞渡时间比线性插值方法的结果更准确。回流式风洞实验结果表明:对相关函数进行三次样条插值可获得较高的测量精度,在1~8 m/s测速范围内的最大测量误差为3.62%,同时计算耗时仅为传统互相关方法耗时的1/258。因此,低采样率声波法测量气体流速可得到较高的精度,可作为电站烟气流速测量的有效方法。In order to solve the problem of large amount of computation and long time-consuming in the existing acoustic velocity measurement method,an online measurement method of flue gas rate at the denigration outlet of power station based on the method of the interpolation of acoustic signal correlation function was proposed.The feasibility of interpolating the acoustic signal cross-correlation function at a lower sampling rate to obtain an accurate signal delay was studied.The numerical simulation results show that the time of flight obtained by cubic spline interpolation method is more accurate than the linear interpolation method.The results of the backflow wind tunnel test show that the cubic spline interpolation of the correlation function can obtain higher measurement accuracy,and the maximum measurement error is 3.62% in the range of 1~8 m/s.By the way,the computational time is only 1/258 of the time consumed by the traditional cross-correlation method.Therefore,the low sampling rate acoustic wave method can accurately measure the flue gas flow rate at the denigration outlet,which can be used as an effective method for measuring the flue gas flow rate of the power plants.

关 键 词：声波法 低采样率 互相关 插值 脱硝出口 烟气流速 

分 类 号：TK313[动力工程及工程热物理—热能工程]