Enhanced Effect of Bubble Deformation on Internal Particle Transport

Abstract

Separation of gas-borne particles by a single bubble is the physical basis of bubble scrubbing in industries. In this work, detailed, high-resolution numerical simulations have been performed on the purification process based on a combined volume-of-fluid−discrete phase model (VOF− DPM) method. Formation and rise of a single bubble over a wide range of Reynolds number (850 < Re < 5000) coupled with internal particle transport are studied. Results show that 5−7 mm bubble (1200 < Re < 1600) evidently deforms, and particle collection efficiency η is rather higher within the range. Emphasis is put on the investigation of the underlying mechanisms contributing to the enhancement of deformation, especially the bubble internal flow patterns and wake behavior. The radial velocity component arises, and hence, the convection mechanism works. The key lies in the synergy between fields of gas velocity and particle concentration, and the synergy angle θ m is proposed to interpret.

Application Effect Analysis of the Mie Scattering Theory Based on Big Data Analysis Technology in the Optical Scattering Direction

“…At present, thermocouples are often used to measure. However, the research on the optical characteristics of wake is still in its infancy in China because of military secrets, which have not been reported abroad for practicality [3]. This research can further grasp the wake structure and physical properties in theory and promote the development of military detection in practice.…”

Improving Fine Particle Removal Using a Single-Channel Slit Bubbling Device in Wet Flue Gas Desulfurization System

“…Because actual coal-fired flue gas was extracted and used as the PM source in this particle removal experiment, this resulted in the flue gas temperature, PM concentration, and particle size distribution having certain fluctuations attributed to the complexity of the combustion conditions of industrial CFB. Different particle concentrations and particle sizes have different capture efficiencies because particles with different particle sizes have different motions and capture mechanisms . Hence, it was impossible to replicate each set of experiments.…”

“…The particle removal mechanism is shown in Figure . The flue gas entrained with particles entered the particle scrubbing device through a 20 mm high slit, aroused a large number of bubbles, and removed particles by contacting the bubble internal liquid film due to the particle motion mechanism that included the inert force, Brownian motion, the diffusional force, the thermophoretic force, and the drag force. , …”

“…Different particle concentrations and particle sizes have different capture efficiencies because particles with different particle sizes have different motions and capture mechanisms. 35 Hence, it was impossible to replicate each set of experiments. The experiments were repeated at similar concentrations and consistent scrubbing experimental conditions.…”

“…Submicron particles belong to the penetrating particle size range, and particles larger than 1 μm are strongly affected by the inertial force 26 and can move to the surface of the bubble liquid film and be captured by the liquid film. 35 3.3. Effect of the Scrubbing Liquid Volume on the Particle Removal Performance.…”