冷卻圓柱尾流特性之有效雷諾數研究

A Study on Effective Reynolds Number by using the Wake Characteristics of a Cooled Circular Cylinder

杜文允(Wen-Yun Tu)

指導教授 ： 王安邦

國立臺灣大學/工學院/應用力學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.02902

摘要

本文針對恆溫冷卻圓柱尾流在高溫層流之實驗，研究圓柱表面溫度與自由流溫度比小於1 (T*< 1)時，溫度效應對圓柱尾流渦旋剝離之影響。自Lecordier et al.(1991) 提出有效雷諾數概念至今，已有許多加熱圓柱方面的實驗(T*> 1)，然而卻從未有加熱流場冷卻圓柱方面的實驗，圓柱尾流的熱效應經本文完成0.67

關鍵字

冷卻圓柱 ； 圓柱尾流 ； 渦旋剝離 ； 有效雷諾數 ； 有效溫度

並列摘要

The paper deals with a non-isothermal case T*<1 of an airflow around circular cylinder in cross flow at the regime of laminar vortex shedding. Lecordier et al.(1991) originally proposed the effective Reynolds number and effective temperature concept. Wang et al. (2000) derived Teff from experiments proposed c=0.28 and St-Reeff curve for T* between 1 to 2. The thesis confirm that Wang et al.(2000) effective temperature and St-Reeff curve for T*<1.
This thermal effect is consistent with known effect of flow stabilization by cylinder heating.

並列關鍵字

cooled circular cylinder ； cylinder wake flow ； vortex shedding ； effective Reynolds number ； effective temperature

參考文獻

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