水平管段塞流液塞速度波动的非线性分析

A FLUCTUATION ANALYSIS OF SLUG VELOCITIES FOR TWO-PHASE SLUG FLOW IN A HORIZONTAL PIPE

利用非线性分析技术中的分形理论在较宽的流速范围内对水平管空气-水段塞流中的液塞速度波动特性进行了研究。结果表明,水平管道段塞流的液塞速度符合正态分布,其波动是对初始条件敏感的混沌振荡,遵循分形统计规律,且具有持久性。通过对不同折算液速下的液塞速度 波动特性的分析发现,当混合速度U_m=11m/s,即其约等于该工况下压力波传播速度时,液塞速度波动的Kolmogorov熵会出现极值,从而发现了液塞速度波动的混沌特征与实际两相流动特征之间的内在联系。在实际应用中,可以通过改变系统的折算液速,优化液塞速度波动的长程相关性。

The fluctuation characteristics of slug velocities have been investigated on basis of fractional theory for air/water slug flow in horizontal pipe within a large variation range of gas and liquid velocities. The results show that distributions of slug velocities can be well fitted by normal distributions, and the fluctuations are some chaotic vibrations, which are sensitive to initial conditions. The results also indicate that the fluctuations obey fractional statistics laws, and keep permanent characteristic. By carrying out an analysis about the fluctuations of slug velocities at two superficial liquid velocities, the authors find that the Kolmogorov entropy of slug velocities will show extremum while the superficial mixture velocity approximates the corresponding pressure wave speed (Um=11m/s). Based on the result, they explored the substaintial correlation between the chaotic characteristics of slug velocities and the intrinsic characteristics of gas-liquid two-phase flow. By changing superficial liquid velocities, the long-range dependence properties of slug velocities fluctuations can be optimized.