首页> 外文期刊>International Journal of Heat and Mass Transfer >Numerical study of hot and cold spheroidal particles in a viscous fluid
【24h】

Numerical study of hot and cold spheroidal particles in a viscous fluid

机译:粘性流体中冷热球体颗粒的数值研究

获取原文
获取原文并翻译 | 示例
           

摘要

The gravity-driven motion of rigid particles with a temperature difference with respect to the surrounding viscous fluid is relevant in many natural and industrial processes, yet this has mainly been investigated for spherical particles. In this work we study the influence of the Grashof number (Gr) on the settling velocity and the drag coefficient C_D of a single spheroidal particle of different aspect ratios (1/3, 1 and 3). The discrete forcing immersed boundary method (IBM) is employed to represent the fluid-solid interaction in both momentum and temperature equations, while the Boussinesq approximation is used for the coupling of momentum and temperature. The simulations show that the drag coefficient of any spheroidal particle below the onset of secondary motion can be predicted by the results of the settling spheres at the desired Grashof number as the main effect of the particle shape at low Galileo number (Ga) and sufficiently small Gr/Ga~2 is found to be the change in the frontal area of the particle. Furthermore, we identify the regions of stable sedimentation (vertical path) in the Ga - Gr/Ga~2 plane for the 3 particle shapes, investigated in this study. We show that the critical Ga beyond which the particle exhibits the zigzagging motion, is considerably smaller for oblate particles in comparison to prolate ones at low Gr/Ga~2. However, both spheroidal shapes indicate a similar behavior as Gr/Ga~2 increases beyond 0.5.
机译:在许多自然和工业过程中,相对于周围的粘性流体,具有温差的刚性颗粒的重力驱动运动是相关的,但是,主要针对球形颗粒进行了研究。在这项工作中,我们研究了格拉斯霍夫数(Gr)对不同纵横比(1 / 3、1和3)的单个球形颗粒的沉降速度和阻力系数C_D的影响。离散强迫沉浸边界方法(IBM)用于表示动量和温度方程中的流固耦合,而Boussinesq近似用于动量和温度的耦合。仿真表明,在次级运动开始以下的任何球形颗粒的阻力系数都可以通过在所需的Grashof数下的沉降球的结果来预测,这是低伽利略数(Ga)和足够小时颗粒形状的主要影响发现Gr / Ga〜2是颗粒正面面积的变化。此外,在本研究中,我们确定了在Ga-Gr / Ga〜2平面中3种颗粒形状的稳定沉积(垂直路径)区域。我们表明,与扁桃形颗粒相比,扁豆形颗粒在低Gr / Ga〜2时,超出极限的Ga呈锯齿形运动,而扁桃形颗粒则明显较小。然而,两个球体形状都表示出类似的行为,因为Gr / Ga〜2的增加超过0.5。

著录项

  • 来源
    《International Journal of Heat and Mass Transfer》 |2020年第3期|119206.1-119206.12|共12页
  • 作者

  • 作者单位

    School of Mechanical Engineering Shiraz University Mollasadra Street Shiraz 71348-51154 Iran;

    Linne Flow Centre and SeRC (Swedish e-Science Research Centre) KTH Mechanics Stockholm SE-10044 Sweden;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    Direct simulation; Heat transfer; Sedimentation; Non-spherical;

    机译:直接模拟;传播热量;沉降;非球形;

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