Lagrangian modelling and visualization of rosette outfall plumes

Abstract

A recently-developed Lagrangian jet model (JETLAG) is combined with visualization technology to give virtual reality simulations of three-dimensional rosette-shaped jet groups issuing from ocean outfalls. The main features of the new entrainment formulation in the Lagrangian model, in particular the prediction of mixing in the weak-strong current transition, and the coflowing jet, are described. Representative comparisions of model predictions with experimental data are presented. The incorporation of computer graphic techniques to develop a PC-based, interactive flow visualization tool is summarized. The resulting model, VISJET, portrays the evolution and interaction of multiple buoyant jets discharged at different angles to the ambient tidal current. The model enables the determination of the degree of merging of the interacting plumes, and is capable of communicating the predicted environmental impact effectively to the stakeholders.