管道内稀疏颗粒相图像法多参数测量  

Measurement of Multi-Parameters for Dilute Granular Phase in Pipes Using Image Method

作　　者：周骛[1] 胡嘉睿 蔡小舒[1] 

机构地区：[1]上海市动力工程多相流动与传热重点实验室(上海理工大学),上海理工大学颗粒与两相流测量研究所,上海200093

出　　处：《工程热物理学报》2015年第3期541-544,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金项目(No.51206112;No.51327803);上海市自然科学基金青年项目(No.12ZR1446900);上海市教委科研创新项目(No.12YZ110)

摘　　要：本文研究了基于单帧单曝光图像的颗粒多参数测量方法,以同时测量包括颗粒相的粒径、速度、浓度和流量等直接反映颗粒相流动特征的参数。由于镜头景深有限,不在景深范围内的颗粒成像将出现离焦模糊现象,且不同粒径大小的颗粒在同一位置被识别的精度不同,因此需要在现有的单帧单曝光法基础上,对拍摄到的模糊颗粒图像进行粒度修正,以获得颗粒的真实粒径和其它参数。采用背光照明方式对8 mm×8 mm方管内水-Al_2O_3颗粒两相流动过程进行图像法测量,对基于模糊图像处理的颗粒相多参数测量方法进行了验证。A measurement method based on single frame single exposure imaging is investigated for multi-parameters of dispersed granular phase,including size distribution,velocity distribution,concentration and volumetric flow rate.Because of the limited depth of field,particles out of that will have defocused images on the image sensor.And different size leads to different measurement accuracy at the same imaging location.So correction from defocus should be carried out on the information of particle size to get accurate results.The measuring method for multi-parameters of dilute granular phase based on processing of defocused images is validated by the experiments on water- Al_2O_3 flow in a 8 mm×8 mm rectangular tube using backward illumination.

关 键 词：图像法 稀疏颗粒相 多参数测量 离焦 轨迹 

分 类 号：O359[理学—流体力学]