• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Textile Research Journal >Role of Baffles on Flow Fields Inside Wet-Lay Mixing Tanks and Their Potential Influence on Fiber Dispersion
【24h】

Role of Baffles on Flow Fields Inside Wet-Lay Mixing Tanks and Their Potential Influence on Fiber Dispersion

机译：挡板对湿式混合罐内流场的作用及其对纤维分散性的潜在影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Dispersion and separation of fiber bundles requires exposing them to a shear stress field to overcome interfiber frictional forces. To this end, fiber-mixing tanks are equipped with baffles to enhance shear and agitation in the water to help disperse the fiber bundles. The time and agitation required to separate and disperse the fibers depends on the fibers being used. It is well known, however, that excessive agitation will give rise to the formation of rope defects in the output because of the high-energy vortices that form behind these baffles. Optimizing the baffle geometry and position is therefore critically important in the wet-lay process. This paper presents some possible ways of eliminating the regions in the water velocity field where strong vortices may be present; in particular, the motivation for this paper is that minimizing vortex formation will lower the probability of rope formation. In this regard, we present a series of numerical simulations to model fluid-flow behavior inside wet-lay mixing tanks. A turbulent flow field is obtained by solving the Navier-Stokes equations in a two-dimensional geometry. The turbulent features of the flow are captured using the RNG k-e model. Fibers, modeled as spherical rigid particles with the same volume as the fibers, are introduced into the solution domain and their trajectories are tracked inside the mixing tank. The effects of the baffles and their orientation with respect to flow streamlines are simulated. We report the simulation results for different baffle configurations and show that aligning the baffles with the streamlines and increasing their surface area can eliminate the formation of vortices while still keeping the shear field at a satisfactory level. We hypothesize that eliminating the vortices in the mixing tank reduces the probability of rope formation, but this hypothesis needs to be verified experimentally.
机译：纤维束的分散和分离需要将它们暴露在剪切应力场中，以克服纤维间的摩擦力。为此，纤维混合罐配备了挡板，以增强水中的剪切和搅动，以帮助分散纤维束。分离和分散纤维所需的时间和搅拌取决于所使用的纤维。但是，众所周知，由于在这些挡板后面形成高能涡流，过度搅拌会在输出中引起绳索缺陷的形成。因此，优化挡板的几何形状和位置在湿法铺设过程中至关重要。本文提出了一些可能的方法来消除水流速度场中可能存在强涡旋的区域。特别是，本文的动机是使涡旋形成最小化将降低绳索形成的可能性。在这方面，我们提出了一系列数值模拟，以对湿式混合罐内的流体流动行为进行建模。通过求解二维几何中的Navier-Stokes方程获得湍流场。使用RNG k-e模型捕获流的湍流特征。将具有与纤维相同体积的建模为球形刚性粒子的纤维引入溶液域，并在混合槽内跟踪其轨迹。模拟了挡板的影响及其相对于流线的方向。我们报告了不同挡板配置的仿真结果，结果表明，将挡板与流线对齐并增加其表面积可以消除旋涡的形成，同时仍将剪切场保持在令人满意的水平。我们假设消除混合罐中的涡流会降低绳索形成的可能性，但是该假设需要通过实验进行验证。

著录项

  • 来源
    《Textile Research Journal》 |2003年第7期|p.575-582|共8页
  • 作者

    H. VAHEDI TAFRESHI; B. POURDEYHIMI;

  • 作者单位

    Nonwovens Cooperative Research Center, North Carolina State University, Raleigh, North Carolina 27695, U.S.A.;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 纺织工业、染整工业;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号