• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>International Journal of Heat and Mass Transfer >Exploration of nanofluid pool boiling and deposition on a horizontal cylinder in Eulerian and Lagrangian frames
【24h】

Exploration of nanofluid pool boiling and deposition on a horizontal cylinder in Eulerian and Lagrangian frames

机译：欧拉和拉格朗日框架中水平圆柱体上纳米流体池沸腾和沉积的探索

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

In spite of many advantages of using nanoparticles in convective heat transfer, there are still some hidden aspects of nanofluids regarding simulations. Pool boiling flows are complicated regarding analytical aspects, and the presence of particles can noticeably extend this complexity. One of the most important aspects of nanofluid pool boiling is concerned with the changes in nucleation site and bubble diameter due to particles deposition and surface roughness. To include these effects, new correlations are implemented as a user-defined function for nucleation site density and bubble departure diameter. On the other hand, the particles are introduced and tracked everywhere in the domain in the Lagrangian frame by using discrete model. As an application, a tube bundle with four tubes is considered with different orientation angles concerning each other and different pitch distances. Unsteady Eulerian two-fluid model in ANSYS-Fluent is employed to simulate the liquid and vapour flows in the computational domain. In this work, pool boiling nanofluid flow is numerically solved around a two-dimensional horizontal cylinder with 20 mm diameter and compared with experimental data. The nanofluid is consist of distilled water and aluminium oxide with a particle size of 38 nm. The good agreement is found, and further discussion regarding particles migration and deposition are presented. It is found that the percentage of deposition is dependent on heat flux and particle concentration. Also, heat transfer coefficient increases with expanding the horizontal distance between cylinders and then decreases to a fixed value.
机译：尽管在对流换热中使用纳米颗粒有许多优点，但在模拟方面，纳米流体仍然存在一些隐藏的方面。池沸腾流动在分析方面很复杂，并且颗粒的存在可以显着扩展这种复杂性。纳米流体池沸腾的最重要方面之一是由于颗粒沉积和表面粗糙度导致的成核位置和气泡直径的变化。为了包括这些效果，新的相关性被实现为用户定义的成核点密度和气泡离开直径的函数。另一方面，通过使用离散模型，粒子在拉格朗日框架中的域中的任何地方被引入和跟踪。作为应用，考虑具有四个管的管束，它们具有彼此相关的不同定向角和不同的节距。 ANSYS-Fluent中的非稳态欧拉二流体模型用于在计算域中模拟液体和蒸汽的流动。在这项工作中，在直径为20mm的二维水平圆柱体周围，对池沸腾的纳米流体流进行了数值求解，并与实验数据进行了比较。纳米流体由蒸馏水和​​粒径为38 nm的氧化铝组成。找到了良好的协议，并提出了有关颗粒迁移和沉积的进一步讨论。发现沉积的百分比取决于热通量和颗粒浓度。另外，传热系数随着气缸之间的水平距离的增大而增加，然后减小至固定值。

著录项

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