Scholarlink

<p>Effect of bed and sphere diameter on natural convection heat transfer in the self-heating, constant temperature packed bed was investigated experimentally. Based on the analogy concept, mass transfer experiments were performed using a copper electroplating system. The sphere diameter was varied by 0.004, 0.006 and 0.01 m, which corresponds to a <i>Ra</i><sub><i>d</i></sub> range of 5.43 × 10<sup>6</sup> - 8.48 × 10<sup>7</sup>. The ratio of bed diameter to sphere diameter ranged from 5 to 30, which covers the range of existing pebble bed reactor design. Also, the ratio of bed height to sphere diameter ranged from 5 to 20. The heat transfer degraded with the increase of bed diameter and bed height. The preheating effect appeared due to the constant temperature heating condition and increased with the packed bed height. Separate measurements of heat transfers in the core and wall regions revealed that the heat transfer degradation was attributed to that in the core region. We developed natural convection heat transfer correlation for the influences of sphere diameter, bed height and bed diameter.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

The local porosity influence on natural convection heat transfer of packed beds with large bed diameter at constant temperature

  • 期刊论文

  • 发表日期：

    2025年11月8日

查看全文
  • Sang-Soo Yoon,
  • Hyun-Ha Ahn,
  • Bum-Jin Chung

摘要

Effect of bed and sphere diameter on natural convection heat transfer in the self-heating, constant temperature packed bed was investigated experimentally. Based on the analogy concept, mass transfer experiments were performed using a copper electroplating system. The sphere diameter was varied by 0.004, 0.006 and 0.01 m, which corresponds to a Rad range of 5.43 × 106 - 8.48 × 107. The ratio of bed diameter to sphere diameter ranged from 5 to 30, which covers the range of existing pebble bed reactor design. Also, the ratio of bed height to sphere diameter ranged from 5 to 20. The heat transfer degraded with the increase of bed diameter and bed height. The preheating effect appeared due to the constant temperature heating condition and increased with the packed bed height. Separate measurements of heat transfers in the core and wall regions revealed that the heat transfer degradation was attributed to that in the core region. We developed natural convection heat transfer correlation for the influences of sphere diameter, bed height and bed diameter.