磨齿倾角对等距直齿磨盘磨区流动参数影响的数值模拟研究

Numerical Simulation Study on the Influence of the Bar Angle on Pulp Flow Parameters in Refining Zone of the Straight Bar Plate

关键词:  盘磨机  等距直齿磨盘  磨齿倾角  浆料流动  数值模拟

Key Words:disc refiner  isometric straight bar plate  bar angle  pulp flow  numerical simulation

摘要:磨齿倾角是直齿磨盘的重要参数之一，其会直接影响磨区浆料流动及磨浆质量。本课题运用Fluent软件对9种不同磨齿倾角的等距直齿磨盘磨区的浆料流动进行了研究，分析了磨齿倾角对出口平均速度、磨盘间隙和沟槽间浆料流动的影响，并结合实验数据与模拟结果推测磨齿倾角对磨浆质量和效率的影响。结果表明，出口和沟槽的平均流速随着磨齿倾角的增大而增大，磨齿倾角过大会使得磨区内浆料螺旋运动减少，虽可提高磨浆产量，但磨浆质量会有所下降。因此，通过合理选择磨齿倾角，可以调控浆料在磨区的停留时间及流动参数进而提升磨浆的质量。

Abstract:Bar angle is one of the most important parameters of the straight bar plate， which will directly affect the pulp flow and the refining quality during low consistency refining. In this study， Fluent software was used to simulate the pulp flow state in the refining zone of isometric straight bar plate. The influence of the bar angle on the average velocity at the outlet， the pulp flow in gap clearance of the plates and grooves were analyzed. The quality and efficiency of pulp refining by straight bar plates with different bar angles were speculated by considering both experimental data and the results of simulation. It was found that the velocity of outlet and grooves increased with the increase of bar angle， and the larger bar angle of refining plates could reduce the spiral motion of the pulp in refining zone. Thereby while the output increased， the refining quality decreased. Thus， the fiber residence time， flow parameters in the refining zone， and the pulp quality could be adjusted by reasonable design of bar angle.