Abstract For low Prandtl-number fluids, heat-transfer characteristics under the influence of the aspect ratio for buoyancy-driven recirculating flows in rectangular enclosures (with left hot, right cold, top/bottom insulated walls) behave differently from those for high-Pr fluids. At Ra = 10 6 and Pr = 0.025 , as the enclosure widens, time-averaged and hot-wall-spatially-averaged heat transfer first decreases, then cascades downward. Locally, heat transfer peaks at a few locations, and these peaks travel cyclically as time elapses. For completeness, the present study serves as a sequel of a previous high-Pr investigation.

中文翻译：

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低普朗特数下外壳纵横比影响的级联和循环传热特性

摘要 对于低普朗特数流体，矩形外壳（左热、右冷、顶/底隔热壁）中浮力驱动的再循环流在纵横比影响下的传热特性与高Pr 的流体不同。流体。在 Ra = 10 6 和 Pr = 0.025 时，随着外壳变宽，时间平均和热壁空间平均传热首先减少，然后向下级联。在局部，传热在几个位置达到峰值，并且这些峰值随着时间的流逝而循环传播。为完整起见，本研究是先前高 Pr 调查的续集。