气固两相流超声过程层析成像系统研究  

Ultrasonic process tomography system for gas-solid two-phase flow measurement

作　　者：田昌[1] 苏明旭[1] 顾建飞[1] 

机构地区：[1]上海理工大学能源与动力工程学院上海市动力工程多相流动与传热重点实验,上海200093

出　　处：《仪器仪表学报》2016年第3期586-592,共7页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(51176128;51206113)项目资助

摘　　要：研究了一种应用于气固两相流过程监测的超声波层析成像系统。为利用少数传感器实现较精确成像,研制了一套测试系统:传感器阵列由8个扇形空气耦合传感器组成,每个传感器均为收发一体式并且发射扇形波束角度可达150°;设计了基于单片机的切换装置以改善系统实时性;发展了改进二值逻辑反投影图像重建算法,通过设置双阈值改善边缘效应提高了图像重建精度。对四氟乙烯棒进行的静态实验与对煤粉进行的动态测试实验中,系统获得了足够多的有效信号数据,实现了气固两相流横断面的二维图像重建。静态实验中重建图像的最小空间成像误差(SIE)为3.2%,表明系统具有较好成像精度,可实现气固两相流流动监测。A transmission-mode ultrasonic process tomography system is presented for gas-solid two-phase flow monitoring. To achieve more precise imaging with a small number of sensors,a measurement system is designed as following： the sensor array is composed of eight fan-shaped air-coupled sensors with a fan beam angle of 150 °,and each sensor can serve as transmitter and receiver alternately.The switching device with MCU is designed to improve the system real-time ability of the system. Furthermore,an improved binary logic back projection algorithm is employed to improve the edge effect in image reconstruction. The static experiments with a tetrafluoroethylene rod and dynamic test experiments with pulverized coal and quartz sand are carried out respectively. Enough effective signal data are obtained and Gas-solid flow cross-section of the two-dimensional image reconstructions are achieved. The spatial imaging error of the system can reach 0. 032. It manifests that the presented system can be used for monitoring the gas-solid two-phase flow.

关 键 词：气固两相流 超声法 层析成像 二值逻辑反投影算法 

分 类 号：TH89[机械工程—仪器科学与技术] TK31[机械工程—精密仪器及机械]