Experimental Study of Vertical Two-dimensional Diffusion Concentration Distribution in Sloped Wave Bank Angular Field

• 作者: Bing GUO Changai ZHANG Hongtao SHAN Li YAO Shurong XIN Xiuying YU Zhengtao YANG Zhouhu WU
• 来源期刊: 农业生物技术:英文版
• 学科: 工学
• 关键词: Sloped WAVE BANK Digital image processing Concentration distribution Experimental research
• 年，卷（期）: 2020,（1）
• 页码范围: 101-109
• 页数: 9页
• 分类号: TG1

摘要

[Objectives] This study was conducted to detect the two-dimensional diffusion concentration distribution from sloped wave bank. [Methods] Diffusion experiments of instantaneous line source discharge were carried out using two sloped wave banks with different inclination angles based on the developed two-dimensional diffusion tank device for sloped wave banks by the apex discharge method under grid oscillation frequencies n=15, 20, 40 and 60 r/min. The image acquisition and digital image processing techniques were applied to measure the two-dimensional concentration field distribution and to analyze the distribution laws of the pollutant in the angular field. [Results] The diffusion of the pollutant in the sloped wave bank area became faster with the increase of the grid oscillation frequency, and the pollution range became wider with the diffusion time. The point concentration of the pollutant at the water surface monotonically decreased with the increase of the abscissa, and the vertical concentration distribution decreased with the increase of water depth. The transverse diffusion rate of the pollutant in water was greater than the vertical diffusion rate, and its concentration distribution exhibited a distribution characteristic of farther diffusion in the adjacent area on the water surface. The diffusion experiment area of the sloped wave bank at θ=30° had a higher concentration of the pollutant at each point compared with the diffusion experiment of the sloped bank at θ=45°, under the same experimental conditions. A large-scale vortex appeared near the sloped wave bank at θ=45° during the experiment, and the presence of the vortex made the concentration distribution of the pollutant in the direction along the bank slope first decrease and then increase, while no obvious vortex was observed near the sloped wave bank at θ=30°, and the concentration of the pollutant decreased monotonously along the bank slope direction. [Conclusions] This study is of great significance for the concentration distribution