在常温常压下,利用水平放置在机械传动的摇摆台架上的两相流实验装置,对内径为34.5mm有机玻璃管内的单相水在不同摇摆状态下的摩擦压降特性进行了试验研究。应用能量方程和Darcy公式求解了摇摆状态下单相水的摩擦阻力系数。试验结果表明:流速、摇摆周期和摇摆幅值等因素对摩擦压降都有一定的影响,并且摇摆状态下的摩擦系数与稳态时不同,呈现周期性的变化。通过引入摇摆雷诺数和实验数据的拟合,提出了用于计算摇摆状态下单相水的摩擦阻力系数的试验关联式。与实验值比较,计算值能够反映摩擦阻力系数的变化,两者符合得很好。
Friction pressure drop of single-phase liquid in rolling tube with inner diameter 34.5mm was investigated to develop a general correction of friction factor. The test section was horizontally settled on the rolling platform, which was driven by link gearing and rotated around a set axis. Friction factor is obtained by applying for the energy equation and the Darcy formula. Comparing the experimental results between the rolling and stable state, it is found that the frictional pressure drop depended on not only the flow velocity, tube diameter, but also the rolling period, rolling angle and etc. It is also found that the rolling friction factor dis- played the periodic change. By defining rolling Reynolds number and applying dimensional analysis, a new correction of single-phase friction factor is provided incorporating the effects of rolling parameters. The proposed correction can well predict the experimental data.