Large-eddy simulations of a sediment plume released by a dredger using overflow. Issue 1 (2nd January 2018)

• Record Type: Journal Article
• Authors: Decrop, B.; Sas, M.; De Mulder, T.; Toorman, E.A.
• Is Part Of: Journal of applied water engineering and research. Volume 6:Issue 1(2018)
• Page Start: 62
• Page End: 69
• Publication Date: 2018-01-02
• Subjects: Trailer Suction Hopper Dredgers -- turbidity plumes -- large-eddy simulation -- computational fluid dynamics; Water-supply engineering -- Periodicals; Water-supply engineering; Periodicals; 627.05
• DOI: 10.1080/23249676.2016.1209441
• Languages: English
• ISSNs: 2324-9676

Abstract

Abstract : Sediment plume predictions are part of the assessment of environmental impacts of dredging. The main source of turbidity while employing Trailer Suction Hopper Dredgers is the release of excess water through the overflow shaft. The near-field plume dynamics below and directly behind the sailing hopper dredgers are traditionally unknown during predictions of far-field plume dispersion. Indeed, an accurate input of the vertical and horizontal distributions of sediment at the source location is important to obtain reliable results at environmentally sensitive areas further away. In this paper, a computational fluid dynamics model is presented as a tool to determine the three-dimensional flows of water, sediment and air bubbles directly after release from the overflow shaft. The full dredger hull geometry and an actuator disc accounting for propeller action are included. It is shown that the model can reproduce two different cases of overflow plumes measured in the field with fair accuracy.