水平携带床内玉米秸颗粒速度场的PIV实验研究

为研究生物质颗粒在水平携带床中的流动特性,搭建了水平携带床透明模拟装置。利用PIV无接触测量技术,在氩气流量为1.9m3/h工况下,对60~160目粒径的玉米秸颗粒流进行了速度场的研究。计算出了颗粒和氩气的平均速度以及流经水平携带床的时间,对颗粒与氩气的跟随性进行了分析。研究结果表明,颗粒流的轴向速度沿轴方向不断增大,管道中心附近的颗粒加速最为明显,而边壁附近的颗粒速度变化相对较慢;颗粒流的速度沿径向大致呈抛物线状分布;颗粒流的平均运动速度比氩气低,颗粒流通过水平床的平均时间略大于氩气。

Experimental study on velocity field of corn stalk granules in horizontal entrained bed by PIV

A horizontal entrained bed made of transparent glass was design and built in order to study the movement characteristics of biomass granules.Using a non-instructive technique of Particle Image Velocimetry(PIV),the velocity fields of corn stalk granules which mesh size ranges from 60 to 160 were studied at the 1.9m~3/h volume flux of Argon gas.The mean velocity and time passing the horizontal entrained bed of the particles and Argon gas were obtained and the difference between the granules and the gas movement in mean velocity was analyzed.The researches show that the axial velocity of the granules accelerates along axis and especially,the central velocity along axis of the bed increased remarkably,while the velocity of the granules near the bed wall changes slowly.The velocity distribution of the granules flow is like a parabola along radius.The mean velocity of the granules is lower than the gas,so the time passing the bed is longer than the gas.