集聚纺集聚区气流流动规律及集聚效果的数值研究

Numerical Investigation on the Airflow Characteristics and Condensing Effect in the Condensing Zone of Compact Spinning

为探讨网格圈式集聚纺集聚区气流流动规律及气流对须条的集聚效果,建立计算流体动力学(CFD)模型,对集聚纺集聚区的气流流动进行了三维数值研究,并根据计算结果就气流对须条进行集聚的机理、几个重要的结构参数及工艺参数(如吸风槽倾角、吸风槽形状、吸风槽宽度及集聚负压)对集聚效果的影响进行了分析.研究结果表明:集聚区的气流静压值低于外界的大气压力,集聚区外围越靠近吸风槽,压力越小,气流速度越高.由于内外压力差和速度差的存在,从前罗拉钳口输出的纤维须条向吸风槽汇聚,宽度逐渐变窄.吸风槽倾角为10°时有利于集聚效果的提高;弧线型和折线型吸风槽的集聚效果优于直线型吸风槽;集聚负压在一定范围内的变化对集聚效果的影响不明显;增大吸风槽宽度有利于气流对须条的集聚.

To investigate the airflow characteristics and the condensing effect of the airflow on the strand in the condensing zone in the lattice-type compact spinning,a three-dimensional computational fluid dynamics（CFD） model has been developed to simulate the airflow characteristics in the condensing zone in compact spinning.According to the simulation results,the condensing principle of the airflow on the strand,together with the condensing effect of some important structure and process parameters（such as the incline angle,shape,width of the suction slot and the negative pressure） are analyzed.The results show that the static pressure value of the airflow in the condensing zone is lower than the atmospheric pressure.The air pressure decreases and the air velocity increases from the outside approaching the suction slot.The fiber strand issued from the front roller nip converges toward the suction slot and its width gradually decreases.The suction slot with an incline angle of 10° improves the condensing effect.The condensing effects of the suction slots with arc and broken line shapes are better than that with straight shape.The variation of the negative pressure has little influence on the condensing effect.Increasing the width of the suction slot is better for the condensing of the strand.