The Study Of Cross Correlation Time Delay Estimation And Acoustic Measurement Of Gas-Solid Two Phase Velocity

Time delay estimation is an important branch of signal processing.In coal fired power plants,the furnace is harsh and opaque.Acoustic techniques will help to solve complex engineering problems.And acoustic measurement is a non-contact measurement method,which has broad application prospects.In the monitoring of a power plant,the operating parameters matters most.Monitor the parameters will help to adjust the parameters,which can reduce pollutant emissions,improve boiler efficiency and guarantee safety.This paper studies about time delay estimation algorithm,including the basic principle of the cross-correlation,generalized cross-correlation and cepstrum delay estimation algorithm.The programming of the algorithms are developed in Labview.Based on this,a novel time delay estimation algorithm based on quadratic correlation PHAT-? is developed.To explore the feasibility of the algorithm,we did experiments on free space,furnace,tube array,pipelines and so on.Besides,we also discussed the acquisition of acquisition card,microphone,acoustic signal,software and other experimental equipments.The experiment of time delay estimation in free space,furnace,tube array,pipelines and 300MW unit were carried out respectively.The advantages and disadvantages of the delay estimation algorithm under different application conditions are compared.Experimental results show that the new algorithm can be better applied in several scenarios.Finally,the application of time delay estimation in velocity measurement of gas-solid two-phase flow is studied.A first wind speed measurement experimental bench was set up,including feed system,transportation system,signal processing system,material recovery system and measurement system.Compared the advantages and disadvantages of two forms of measurement.The pitot tube was used to measure the speed as a reference flow velocity.The experimental results show that the acoustic velocity measurement measures the average velocity of the pipe section and can provide a reference for practical application.