School of Environment and Municipal Engineering, Xi'an University of Architecture and Technology, Key Laboratory of Northwest Water Resources and Environmental Ecology, Ministry of Education, Xi'an, 710055, Shaanxi, China; School of Environment and Municipal Engineering, Xi'an University of Architecture and Technology, Shaanxi Provincial Key Laboratory of Environmental Engineering, Xi'an, 710055, Shaanxi, China.
Shaanxi Key Laboratory of New Transportation Energy and Automotive Energy Saving, School of Energy and Electrical Engineering, Chang'an University, Xi'an, Shaanxi, 710061, China.
J Environ Manage. 2024 Aug;366:121812. doi: 10.1016/j.jenvman.2024.121812. Epub 2024 Jul 14.
Improving gas-liquid mass transfer efficiency in aeration systems contributes to energy savings, cost reduction, and enhanced efficiency in wastewater treatment. However, due to the complex nonlinear interactions among bubbles in turbulence, understanding the transport mechanisms of non-uniform bubble clusters in turbulence remains unclear. This study employs a combined approach of experimental research and numerical simulations to investigate the shape, diameter distribution, trajectory, and velocity of bubbles under different aeration port sizes and flow rates. The diameter distribution of bubble clusters exhibits a bimodal distribution. Bubble trajectories during ascent mainly exhibit two types of motion patterns: "Z" shaped and linear. Increasing aeration port size and flow rate both lead to an increase in the maximum bubble diameter. Higher initial flow rates and smaller port sizes induce greater lateral velocity fluctuations in bubbles. The proposed numerical simulation method serves as a reference for simulating the transport of non-uniform bubble clusters.
提高曝气系统中的气液传质效率有助于节约能源、降低成本，并提高废水处理效率。然而，由于在湍流中气泡之间存在复杂的非线性相互作用，因此对于非均匀气泡簇在湍流中的输运机制仍不清楚。本研究采用实验研究和数值模拟相结合的方法，研究了不同曝气孔尺寸和流量下气泡的形状、直径分布、轨迹和速度。气泡簇的直径分布呈双峰分布。上升过程中的气泡轨迹主要表现为两种运动模式：“Z”形和线性。增大曝气孔尺寸和流量都会导致最大气泡直径增大。较高的初始流速和较小的孔尺寸会导致气泡的横向速度波动增大。所提出的数值模拟方法可作为模拟非均匀气泡簇输运的参考。
