Flow visualization of natural convection in a tall, air-filled vertical cavity
Flow visualization of natural convection in a tall, air-filled vertical cavity
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DOI：
10.1016/j.ijheatmasstransfer.2005.06.045
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发表时间：
2006-03
影响因子：
5.2
通讯作者：
J. Wright;H. Jin;K. Hollands;D. Naylor
中科院分区：
文献类型：
--
作者：
J. Wright;H. Jin;K. Hollands;D. Naylor
本文用烟雾图和干涉法研究了竖直空腔内空气的自然对流。实验覆盖了4850<Ra<54，800的瑞利数和纵横比A ≤ 40。在低至6228的Ra下观察到次级细胞。流量在Ra<104时稳定。当Ra超过104时，流动变得不规则，核心流动变得越来越不稳定，三维运动变得明显。干涉测量表明，大部分的温降存在于壁面附近的边界层。岩芯混合良好，温度相对均匀，很少或没有垂直分层。
Natural convection of air in a tall vertical cavity was studied using a smoke patterns and interferometry. Experiments covered Rayleigh numbers of 4850<Ra<54,800 and aspect ratio A≈40. Secondary cells were noted at Ra as low as 6228. The flow was stable at Ra<104. As Ra exceeded 104the flow became irregular, the core flow became increasingly unsteady and 3-D motion became evident. Interferometry showed that most of the temperature drop exists in boundary layers near the walls. The core is well mixed and of relatively uniform temperature with little or no vertical stratification.