沿结构壁面下落的非定常液体薄膜的表面波具有复杂的特性. 对不同频率周期性扰动下沿正弦波纹壁面的薄膜流动进行了数值模拟, 并采用流体体积 (volume of fluid, VOF) 法捕捉流体界面, 分析了表面波的空间演化过程. 结果表明, 表面波的演化过程是由扰动频率决定的行波和由壁面结构决定的静态波相互作用的结果. 通过同步压缩小波变换对表面波进行空间频谱分析, 研究了壁面结构对行波波数的影响, 以及行波和静态波之间的动力学行为.
Unsteady film flow along an inclined corrugated wall behaves a variety of complex features. By utilizing volume of fluid (VOF) method to capture the evolution of free surfaces, the liquid falling film along the inclined sinusoidal wall for the different applied frequencies of the periodic disturbance is simulated numerically to study the spatial evolution of the waves. Results obtained indicate that the evolution of the surface wave is dominated by the interaction of the traveling wave induced by the disturbance applied at the inlet and static wave determined by the wall structure. With the application of synchrosqueezing wavelet transforms, the spatial frequency spectrum of the surface wave is analyzed, and the influences of the wall structure on the wave numbers of traveling waves are studied, as well as the dynamical behavior of both traveling wave and static wave.
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