Application of multiresolution analysis for simultaneous measurement of gas and liquid velocities and fractional gas hold-up in bubble column using LDA

Abstract

A new strategy using wavelet transforms for multiresolution analysis of bubble column hydrodynamics from laser Doppler anemometer measurements of the axial velocity has been formulated. The advantage of the methodology is that we may infer intrinsic features of the bubble column hydrodynamics by accurately detecting the passage of bubbles at local positions in the column. The detection of bubbles was possible by denoising local time series data and analyzing for its intermittent behavior. The methodology allows for calculating the changes in the local average liquid velocities and local gas hold-up and was related to the intermittent nature of turbulence in the system. The variation in these properties and flow behavior as a function of radial distance have been studied.