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Physical modelling of mixing processes from ballast water discharge in ports


Cossu, R and MacFarlane, G and Abbassi, R and Carvalho, A, Physical modelling of mixing processes from ballast water discharge in ports, Proceedings of the Australasian Coasts and Ports Conference 2017, 21-23 June 2017, Cairns, Australia, pp. 1-7. ISBN 9781922107916 (2017) [Conference Extract]

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The predominant factor in biological invasion in port areas is the discharge of ballast water from commercial cargo ships which is a global threat to marine ecosystems. We report Rhodamine-WT tracer dye experiments carried out in a contolled environment to simulate ballast water propagation in order to better understand the diffusion and retention characteristics of ballast water discharges in ports at various wave climates. A Cyclops C7 Turner Rhodamine sensor was used to measure dye concentrations in proximity of the discharge point. Several wave heights and wave periods showed different concentration rates. In particular, the wave frequency accelerated the mixing of dye in the wave basin whilst the wave height had less impact on the dilution. However, further testing is imperative to gain a more complete understanding of all the factors affecting diffusion processes. Our findings suggest that this experimental setup is an efficient way to determine mixing and diffusion coefficients to better analyse Ballast Water Management protocols. Future experiments should include the use of multiple sensors and sufficient rest in between experimental runs. With a targeted parameter set of various sea states diffusion coefficients of discharge jets as well as molecular diffusion rates can be determined.

Item Details

Item Type:Conference Extract
Keywords:ballast water management (BWM), diffusion, effective factors, Rodamine-WT, dye tracing
Research Division:Engineering
Research Group:Maritime engineering
Research Field:Ocean engineering
Objective Division:Environmental Management
Objective Group:Marine systems and management
Objective Field:Control of pests, diseases and exotic species in marine environments
UTAS Author:MacFarlane, G (Associate Professor Gregor MacFarlane)
UTAS Author:Abbassi, R (Dr Rouzbeh Abbassi)
UTAS Author:Carvalho, A (Mr Aaron Carvalho)
ID Code:122351
Year Published:2017
Deposited By:NC Maritime Engineering and Hydrodynamics
Deposited On:2017-11-10
Last Modified:2018-02-21

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