螺旋管中二次流强度的数值研究

A Numerical Study of the Intensity of Secondary Flow in Helical Coiled Tube

对螺旋管中充分发展的层流状态下二次流强度进行了数值分析,定义了二次流强度的无量纲化参数——二次流强度雷诺数,得到了迪恩数与阻力系数、二次流强度雷诺数、流量比之间的关系.发现迪恩数与提出的二次流强度雷诺数具有良好的线性关系,这表明迪恩数的另一物理意义是螺旋管中二次流强度的度量.

The intensity of secondary flow in helical coiled tube is studied by numerical method in the ease of fully developed laminar flow. A dimensionless parameter which describes the intensity of secondary flow is defined in the present study,and it is named as the secondary intensity Reynolds number. The relationships between Dean num- ber, friction factor,and the secondary flow intensity Reynolds number, the ration of the flow rate in helical coiled tube to the flow rate in straight tube are obtained. Our studies have found a perfect linear relation existing between Dean number and the secondary flow intensity Reynolds number. The linear relationship shows that the physical meaning of Dean number is a measurement of the secondary flow intensity in helical coiled tube.