Turbulent Kinetic Energy Dissipation in Buoyant Motions

该研究项目考察了浮力对湍动能耗散率的影响。研究了浮力在决定运动中起重要作用的两个问题：由浮力流体源产生的湍流羽流和流体内部密度-界面的垂直混合。实验采用激光多普勒测速仪测量速度，激光诱导荧光测量示踪剂浓度。研究结果将对关注颗粒凝聚力学和溶解物质在密度分层流体中的混合的环境工程师具有实际意义。应用包括废水处理和处置系统的优化设计、水体曝气、二氧化碳等大气气体的溶解以及河口悬浮颗粒的絮凝等过程的描述。

This research project examines the influence of buoyancy forces on the rate of turbulent kinetic energy dissipation. Two problems in which buoyancy forces play a significant role in determining the motion are investigated: turbulent plume generated by a source of buoyant fluid and vertical mixing across adensity- interface within a fluid. The experiments are performed using alaser-Doppler anemometer for velocity measurement and laser induced fluorescence in dye molecules for tracer concentration. The research results will be of practical importance to environmental engineers concerned with particle coagulation mechanics, and the mixing of dissolved materials withindensity-stratified fluids. Applications include the optimal design of waste water treatment and disposal systems, description of processes such as aeration of water bodies, dissolution of atmospheric gases such as carbon dioxide, and flocculation of suspended particles in river estuaries.