振动管外流动与传热实验研究及场协同分析

Experimental research and field synergy analysis of flow and heat transfer outside a vibratory tube

采用实验与数值模拟相结合的方法研究了振动管外的流动及传热特性,利用正交设计方法分析了振幅、频率等参数对换热性能的影响,得到了低频区内换热效果与振动参数间的拟合关联式,并基于场协同理论得到了管外近壁区的协同角余弦值随频率、振幅的变化规律。通过分析发现:振动强化传热的效果随着频率和振幅的升高而显著增强,共振工况下换热最强。对比不同管型的换热性能,沿椭圆管短轴方向振动的传热效果最好,圆管次之,长轴最差,证明管型也为影响振动工况下对流换热性能的重要参数。

Experimental research and numerical simulation were carried on to study the flow and heat transfer characteristics outside a circular and an elliptical tube under vibration condition.The orthogonal design method was used to analyze the effect of amplitude,frequency and shape of the tube on heat transfer performance,and a fitted correlation between heat transfer and vibration parameters was obtained in the low-frequency area.Based on the field synergy theory,in the near-wall region,the dependence of the cosine value of synergy angle on the vibration frequency and amplitude was gained.It is shown that heat transfer is significantly enhanced while the frequency increases,and rises to a peak value when resonance condition appears.Comparison between different kinds of vibration tubes indicates that heat transfer of elliptical tube with vibration in the direction of its short axis is the best,round tube takes second place,and elliptical tube with vibration in the direction of its long axis is the worst.Results show that resonance can greatly enhance heat transfer,and type of vibrating tube is also an important factor affecting the heat transfer.