基于分形理论的液塞长度分析

利用以自相似性为基础的分形理论对管内径为 5 0mm的水平管道的段塞流液塞长度分布进行了统计分析。结果表明 ,水平管中的液塞长度分布遵循分形统计规律 ,充分发展段的平均液塞长度为管径的 11～ 17倍 ,最大液塞长度为管径的 2 5～ 39倍 ,平均液塞长度和最大液塞长度均与气液相混合速度之间具有线性关系。试验研究还表明 ,重标度极差分析法是计算反映液塞长度波动过程具有长程相关性的Hurst指数的有效方法。Hurst指数与气液相混合速度之间具有缓降的线性关系 ,可以用Hurst指数反映出的FBM随机过程的持久性和反持久性预测液塞长度的发展趋势

Length analysis of liquid slug using fractal theory

A series of experiments were carried out to analyze the statistical laws of the length distribution of liquid slug in horizontal pipe based on the fractal theory. The research results indicate that the length distributions of liquid slug in the horizontal pipe flow obey fractal statistics. For the fully developed slug flow, the mean lengths of liquid slug are within 11 to 17 times of the inner diameter of the pipe, and the maximum lengths of liquid slug are within 25 to 39 times of the inner diameter of the pipe. The mean length and the maximum length of liquid slug linearly depend on the superficial mixed velocity of gas and liquid. In addition, the R/S analysis method is an effective method for calculating the Hurst exponent, which reflects the long distance correlativity of the length fluctuation of liquid slug. The Hurst exponent has a slightly linear descending relationship with the superficial mixed velocity of gas and liquid, which reflects the random durability and anti durability. This method is favorable for forecasting the developing trend of the liquid slug lengths quantitatively.