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采用双模颗粒动态分析仪 (DualPDA)同时测定了气流式喷嘴雾化过程中液滴在不同空间位置的三维速度向量、粒度和滞留时间等物理量 ,研究了液滴速度分量、粒度分布及滞留时间的时间序列 ,通过域重新标度分析法 ,计算出时间序列的赫斯特指数、谱密度指数及其分形维数 ,发现各空间点测得的各物理量的归一化域值对时间具有标度性质 ,相对于均值的累积偏差曲线具有自仿射性 ,各物理量的时间序列彼此也具有自仿射性 ,其Hurst指数和分维数分别近似相等 .所得到的结果和前人用激光诱导荧光 (LIF)技术获取湍流 /非湍流界面图像而得到的结果一致 .
The dual-mode particle dynamics analyzer (DualPDA) was used to simultaneously determine the three-dimensional velocity vector, particle size and residence time of droplets in different spatial positions during the atomization process. The effects of drop velocity, particle size distribution and residence time The time series Hearst index, spectral density index and its fractal dimension were calculated through the domain rescaling analysis method. It was found that the normalized value of each physical quantity measured in each space point was marked with time Degree property, the cumulative deviation curve with respect to the mean is self-affine, and the time series of each physical quantity is also self-affine with each other, and the Hurst exponent and the fractal dimension are approximately equal, respectively. The results obtained with fluorescence (LIF) technique for acquiring turbulent / non-turbulent interface images are consistent.