Study On Boiler Tube Leakage Monitoring System Of300MW Circulating Fluidized Bed Boiler

In the recent years, the boiler tube leakage have become a very important reasonwhich affects the unit running safely and economically in power plant. The boiler tubeleakage monitoring system plays a very important role in power plant which can find outearly light leaking points of boiler in time. The boiler tube leakage monitoring systembased on acoustics could monitor the boiler tube leakage in real time and in remote.Because the monitoring technology is not very mature, some problems influence the itsdeveloping severely, such as the acoustic sensors burning out easily, acoustic conductiontube blocking and the inaccurate locating.According to the generation principle of the boiler tube leakage noise and jetstructure, the sound field model of the boiler tube leakage noise was established. Somecharacteristics of the leakage noise was simulated by EASE which was a acoustic designsoftware. For the boiler tube leakage monitoring system turning out the problems such asthe acoustic sensors burning out easily, acoustic conduction tube blocking in circulatingfluidized bed boiler, the principle of the boiler tube leakage monitoring system wasanalyzed and the rehabilitation program of the system hardware was proposed.According to the problem of inaccurate locating in the boiler tube leakage monitoringsystem, a sound source location method was proposed. Time delay was calculated bycross-correlation method which the boiler tube leakage noise reach the acoustic sensorsin four-cross array and the principle of geometry locating was used to locate the soundsource. The characteristics of different cross-correlation method was compared byMATLAB which was a software and time delay estimation deviation was analyzedfurther which influence the location accuracy. In the last, the location method wasresearched by simulation, and the result showed that the location method based on timedelay had a good location property.