深海采矿尾水羽状流扩散的数值模拟

Numerical Simulation of Plume Diffusion in Deep-Sea Mining Tailwater

深海采矿尾水排放形成的羽状流会极大地污染海底环境,针对尾水排放口高度、排放速度和排放口形状影响尾水羽状流扩散的因素,利用FLUENT软件中的DPM模型建立尾水羽状流扩散模型,并通过数值仿真分析羽流扩散形态。仿真结果表明:尾水排放速度高达10 m/s,并迅速到达海床,尾水反射造成羽流二次扩散。围绕尾水排放速度对羽流尺寸的影响问题,优化了深海采矿尾水羽流抑制装置,优化结果表明安装该装置后尾水排放速度降至原来的1/3,羽流扩散幅度减少92.7%,可有效降低尾水排放环境扰动,最大程度保护深海环境。

The plume formed by the tailwater discharge from deep-sea mining greatly pollute the seabed environment.In view of the factors that affect the tailwater plume diffusion such as the tailwater outlet height,discharge speed and outlet shape,a tailwater plume diffusion model is established using the DPM model in Fluent software,and the plume diffusion pattern is analyzed by numerical simulation.The simulation results show that the tailwater discharge velocity is as high as 10 m/s and reaches the seabed rapidly,and the plume secondary diffusion is caused by the tailwater reflection.Focusing on the influence of tailwater velocity on plume size,the tailwater plume suppression device for deep-sea mining is optimized.The optimization results show that the tailwater discharge speed is reduced to 1/3 of the original,and the plume diffusion amplitude is reduced by 92.7%,which can effectively reduce the tailwater discharge environmental disturbance and maximize the protection of the deep-sea environment.