Measurement of fiber suspension flow and forming jet velocity profile by pulsed ultrasonic doppler velocimetry.

Fibers;Suspension;Fluid flow;Forming;Jets;Velocity measurement

Xu, Hanjiang ; Institute of Paper Science and Technology

University:Georgia Institute of Technology

Department:Institute of Paper Science and Technology

关键词: Fibers;    Suspension;    Fluid flow;    Forming;    Jets;    Velocity measurement;   

Others  :  https://smartech.gatech.edu/bitstream/1853/7073/1/xu_hanjiang_200305_%20phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

The flow of wood fiber suspensions plays an important role during the pulp and papermanufacture process. Considerable research has been carried out in the past 50 years tocharacterize the fiber suspension flow behavior and to monitor the fiber suspension flowduring paper manufacture. However, the above research has been hampered by the lackof techniques to directly characterize fiber suspension flow fields because fibers and fiberflocs tend to interfere with instruments inserted into the flow.The fundamental studies in this thesis concentrated on three parts: (1) examine thefeasibility of measuring wood fiber suspension flow by Pulsed Ultrasonic DopplerVelocimetry (PUDV), (2) apply PUDV to characterize fiber suspension flow behavior ina rectangular channel, (3) apply PUDV to measure the forming jet velocity profile alongthe jet thickness direction (ZD). In the first part, it is demonstrated that PUDV is anaccurate technique for the velocity profile measurement of fiber suspension flow. Themeasurement has high repeatability and sensitivity. Suitable parameters should beselected in order to obtain the optimum measuring results.