Structural Analysis of Temperature-Flow Field Interaction Based on Wavelet Frequency Reconstruction and Devernay Algorithm

Gas-liquid Annular flow is a crucial flow pattern in many industrial processes, and the structural analysis of its flow field holds significant research importance. And the wave structures perform a considerable interaction with its temperature. This study employs Planar Laser-Induced Fluorescence to investigate the influence of temperature on the flow field structure. To enhance the extraction of falling film structures, Devernay algorithm is utilized for identifying liquid film boundaries in fluorescence images, thereby preserving intricate details of the liquid film. Considering the distinct frequency ranges of the base wave, disturbance wave, and ripple, wavelet transform is applied. This serves not only to eliminate high-frequency noise introduced by the sub-pixel algorithm but also to separate the three types of waves effectively. Subsequent analysis of the wavelet reveals the dynamic characteristics of the waves, illustrating that elevated temperatures amplify liquid film fluctuations. Disturbance waves become more pronounced with increasing temperature, and the amplitude of ripples become more concentrated. This comprehensive exploration contributes valuable insights into the impact of temperature on the dynamics of liquid film flows in vertical pipes, shedding light on the complex interplay of temperature and flow field structures.