为了使压力筛中的浆料更好地导向筛缝和提高筛选能力，必须减小或消除压力缝筛波纹处的涡流。利用UG软件对筛缝处的局部流场造型，运用FLUENT软件对筛缝处的流场进行数值模拟；分析比较了不同造型的波纹形状，得到流场的压力、湍流动能和速度的分布云图。结果表明：在实验条件下，筛缝入口倒角值越大，筛缝入口处的浆料流体流线形态越平滑；当倒角半径增至04 mm时，涡流状态消失；波纹筛缝入口两侧的圆倒角半径均为05 mm时，浆料流动形态最好，通过率最大，比改进前提高了124 ％。
Abstract
In order to turn the pulp in the pressure screen turn into the slot more easily and to improve the screening ability， the vortex near the contoured slot should be reduced or eliminated. The local flow field model of the screen slot was drawn with UG software， and then the flow field model was simulated with FLUENT software. Different improvements of the contoured slot shape were analyzed， and finally the detail distribution contours of the pressure， turbulent kinetic energy and velocity magnitude in the contoured slot field were obtained. The results showed that in the experimental condition the larger the screen slot chamfering angle was， the smoother the fluid flow near the screen slot was. When chamfering angle radius increased to 04 mm， the vortex disappeared. When the chamfering angle radiuses of the contoured slot entrance on both sides were 05 mm， the pulp flow form was the best， the passage ratio was the largest and improved 124 ％ higher than before.
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基金
收稿日期：2011-12-07修回日期：2012-04-18
基金项目：南京林业大学江苏省制浆造纸科学与技术重点实验室开放基金（201001）；江苏高校优势学科建设工程资助项目（PAPD）
第一作者：陈永利，硕士生。 *通信作者：张辉，教授。 Email： hgzh@njfu.edu.cn。
引文格式：陈永利，张健，张辉. 基于FLUENT的压力缝筛波纹形状的改进机制[J]. 南京林业大学学报：自然科学版，2012，36（6）：105-109.
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