Real Time Temperature Monitoring Of Energy Deposits Based On Acoustic Method

In the process of power production,solid fuels such as coal and biomass usually exist in the form of particle accumulation.These accumulated fuels are prone to slow oxidation exothermic reaction.If it is not found in time,it will produce natural phenomena and cause huge losses to the power production process.Therefore,it is necessary to monitor the internal temperature distribution of the accumulated fuels in real time.Acoustic temperature measurement technology is a new type of non-contact temperature measurement technology in recent years,with its perfect theoretical basis and the advantages of being able to adapt to a variety of harsh temperature measurement environment and so on.This paper mainly studies the propagation characteristics of sound waves in energy deposits through experiments,and verifies the possibility of using acoustics to measure the temperature field of energy deposits.Firstly,according to the theoretical derivation,the energy deposits are divided into particle deposits and powder deposits.In this paper,the process of acoustic measurement of the internal temperature field of energy particle deposits is systematically introduced,and the standard sound velocity at the experimental temperature is calculated.Before the formal experiment,the least square method combined with the theoretical sound velocity at the experimental temperature was used to solve the measurement error of the experimental platform.Then,soybean and mung bean were used to carry out experiments to study the effects of particle diameter,depth and temperature on the sound velocity in the deposit.The process of sound propagation in the deposit was explained by simulation,and the sound attenuation coefficient of sound propagation in different frequency bands was measured.Next,the experiment uses coal powder to explore the propagation characteristics of sound wave in powder accumulation,mainly explores the sound absorption characteristics of accumulated coal powder and the propagation characteristics of low-frequency sound wave in accumulated coal powder.The coal sample is bituminous coal produced by Fuquan coal mine,and four kinds of coal samples with different particle size range are prepared.The absorption coefficient of sound wave and attenuation coefficient of sound wave are studied in turn.The frequency range of the study is 200-2000hz,which verifies the feasibility of acoustic measurement of temperature distribution of accumulated pulverized coal.