...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Energy Conversion & Management >Investigating effects of sphere blockage ratio on the characteristics of flow and heat transfer in a sphere array
【24h】

Investigating effects of sphere blockage ratio on the characteristics of flow and heat transfer in a sphere array

机译：球阻塞率对球阵列中流动和传热特性的影响研究

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

With advantage of higher heat transfer area per unit mass, a pebble bed is usually adopted as an essential component for design of energy production systems and thermal energy storage (TES) systems. The majority of this paper investigates the sphere blockage ratio (β) on the thermal-hydraulic characteristics of a pebble with 14 spheres using a three-dimensional (3-D) computational fluid dynamics (CFD) model with the v~2 -f turbulence model. In a previous work, this model has been validated against measured distributions of the heat transfer coefficient on the selected spheres. The measured data are obtained using the transient liquid-crystal technique. According to the simulation results, the thermal-hydraulic characteristics in the sphere array can be captured reasonably with the present CFD model, including flow stagnation, flow separation, vortex formation and anisotropic characteristics of the heat transfer on the sphere surface. Comparisons of the simulation results for the sphere arrays with different blockage ratios show that the flow and turbulent intensity distributions are similar in most regions of a sphere array, except the portions between the pebbles. The heat transfer coefficient for the upstream spheres increases slightly as the blockage ratio decreases. However, a lower heat transfer coefficient is predicted for the downstream sphere if β is less than 0.75. In addition, the heat transfer coefficient around the front of a downstream sphere would not be influenced by the upstream spheres until ft β≤0.75. Similar results are also revealed in the dependence of the heat transfer coefficient on the zenith angle of the spheres for the different blockage ratios.
机译：由于单位质量的传热面积更大，通常将卵石床用作能量生产系统和热能存储（TES）系统设计的基本组件。本文的大部分内容是使用v〜2-f湍流的三维（3-D）计算流体力学（CFD）模型研究具有14个球体的卵石的热工水力特性的球体堵塞率（β）模型。在以前的工作中，已经针对所选球体上传热系数的测量分布验证了该模型。使用瞬态液晶技术获得测量数据。根据仿真结果，利用现有的CFD模型可以合理地捕捉球阵列中的热工水力特性，包括流滞，流分离，涡旋形成以及球表面传热的各向异性特征。对具有不同阻塞率的球体阵列的仿真结果进行比较，结果表明，在球体阵列的大多数区域中，除了卵石之间的部分之外，流动和湍流强度分布都是相似的。随着堵塞率的降低，上游球体的传热系数略有增加。但是，如果β小于0.75，则预测下游球体的传热系数较低。另外，直到ftβ≤0.75时，下游球体前部附近的传热系数才受到上游球体的影响。对于不同的堵塞率，传热系数对球的天顶角的依赖性也表明了相似的结果。

著录项

  • 来源
    《Energy Conversion & Management》 |2014年第5期|455-464|共10页
  • 作者

    M.T. Kao; Y.H. Tung; Y.M. Ferng; C.C. Chieng;

  • 作者单位

    Dept of Engineering and System Science, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC;

    Dept of Engineering and System Science, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC;

    Dept of Engineering and System Science, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC,Department of Engineering and System Science. Institute of Nuclear Engineering and Science, 101, Section 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan, ROC;

    Dept of Engineering and System Science, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC,Dept of Mechanical and Biomedical Engineering City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region;

  • 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

    Sphere array; Sphere blockage ratio; CFD model; v~2-f Turbulence model;

    机译：球面数组;球体阻塞率;差价合约模型v〜2-f湍流模型;

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