稠密颗粒系统辐射换热算法研究

• 作 者: 吴浩 桂南 杨星团 屠基元 姜胜耀
• 机 构: 清华大学核能与新能源技术研究院,先进核能技术协同创新中心,先进反应堆工程与安全教育部重点实验室,北京100084;皇家墨尔本理工大学工学院,澳大利亚,维多利亚3083
• 出 处: 工程热物理学报
• 发表日期: 2017年12期
• 关键词: particle dense radiation exchange voronoi partition discrete element method (DEM

本文在不同空间尺度下研究稠密颗粒系统的辐射换热,提出短程辐射模型、长程辐射模型和微观模型.长程辐射模型考虑了所有存在辐射换热关系的颗粒对,而短程辐射模型仅考虑距离较近的颗粒球.通过和现有的经验关联式比较,当材料热导率远大于辐射等效热导率时(Λ＞10),长程辐射模型能准确地预测辐射换热.而当两者在同一量级上时,辐射换热被严重高估.此时,短程辐射模型显示出更好的计算精度.“,”In this paper,particle thermal radiation of dense granular systems under different spatial scale is investigated and short-distance radiation model,long-distance radiation model and microscopic model are presented.All possible particle pairs related by thermal radiation are considered in long-distance radiation model and only the ones which are very close to each other are taken into account in short-distance radiation model.By comparing the results with empirical correlations,long-distance radiation model can predict particle thermal radiation in good accuracy when solid conductivity is far greater than effective thermal conductivity (Λ ＞ 10).But when the conductivities are in the same order,particle radiation is overestimated greatly in long-distance radiation model.And then short-distance radiation model provides good prediction for particle radiation.