On the Application of Detached Eddy Simulation Turbulence Modelling to Hydrocyclonic Separators for Shipboard Ballast Water Treatment

There is significant worldwide environmental concern related to the transportation of Invasive Aquatic Species (IAS) by ships ballast water into non-native environments. This has given rise to the development of a vast array of technological ballast water treatment systems. The complex environmental challenges and tight operational characteristics of marine vessels limits the scope of the technologies used for Ballast Water Treatment (BWT). As a result few technologies have progressed beyond the research and development stage; however one of the most promising technologies for ship board use is the cyclonic separator, or hydrocyclone. Despite the use of hydrocyclones in a wide variety of engineering applications they have yet to be successfully adapted towards the removal of suspended sediment and marine organisms from large volumes of ballast water. This study details the operational characteristics of ballast water hydrocyclones with the aim of enabling hydrocyclones to be optimised for individual ship configurations. This study employs Computational Fluid Dynamics (CFD), and in particular the Detached Eddy Simulation (DES) turbulence model. The DES model is shown to be valid for hydrocyclonic flow regimes, validated against empirical and experimental data.