锯齿型通道流动与换热的自维持振荡实验研究

THE EXPERIMENTAL STUDY OF THE SELF-SUSTAINED OSCILLATION OF FLOW AND HEAT TRANSFER IN A CORRUGATED CHANNEL

本文对锯齿型通道内流动与换热的自维持振荡特性进行了实验研究。从可视化实验中观察到,Re<300时,流场随时间几乎没有明显的变化;Re>300,流动出现了明显的回流现象,且随着Re数增大,回流形成的涡增大,流动产生的涡的位置随时间呈有规律的周期性变化;在恒热流边界条件下,通道上、下壁面温度沿流动方向的变化与数值模拟所得到的Nu数、壁温的变化规律一致。

In this paper,the self-sustained oscillation character of flow and heat transfer in the corrugated channel was studied by experimental method.It was obvious according to the visual experiment：there was almost no visible variation with time in the flow field when the Reynolds number was below 300.With the increase of Reynolds number and exceed 300 the Back Layering was obviously observed in the picture of the flow.And also the position of the swirl had a cyclical variation with time.Under the condition of constant heat flow,the distribution of temperature in the upper and lower side of the wall in the channel changed regularly through the flow orientation,which was similar with the variation of the Nu number and the wall temperature according to the result of numerical simulation.