展向局部加热与圆柱尾流的绝对不稳定性  

Research on absolute instability of a cylinder wake at low Reynolds numbers by local heating

作　　者：蒋小勤[1] 杨立[2] 郑学龄[1] 

机构地区：[1]海军工程大学基础部,湖北武汉430033 [2]海军工程大学动力工程学院,湖北武汉430033

出　　处：《海军工程大学学报》2003年第4期1-4,共4页Journal of Naval University of Engineering

基　　金：国家自然科学基金重点项目(编号59236140)

摘　　要：采用对圆柱展向局部电加热的方式,在水槽中实验研究了临界/亚临界雷诺数圆柱尾流的绝对不稳定性.利用可控电加热改变圆柱表面温度分布,对二维圆柱绕流引入局部三维扰动,观察其对于临界/亚临界雷诺数圆柱尾流稳定性的影响.研究表明,在临界雷诺数状态,圆柱绕流尾流具有绝对不稳定性;在亚临界雷诺数状态,圆柱绕流尾流则是对流不稳定的.加热圆柱展向局部涡脱落存在锁频现象.The absolute instability of a cylinder wake has been studied experimentally by local heating in water channel. A 3\|D perturbation is introduced in the wake by electrical heating at the middle of spanwise, which changes the spanwise temperature distribution and the water viscosity near the heated cylinder surface. The experimental results show that the cylinder wake has absolute instability when Re ≈ Rec, but it has convective instability when Re < Rec. The lock\|in phenomenon of the local vortex shedding along the heated cylinder slantwise has been found for the first time. 

关 键 词：雷诺数 圆柱尾流 绝对不稳定性 水槽实验 锁频 旋涡脱落 电加热 

分 类 号：O35[理学—流体力学]