School of Civil Engineering

Projects in coastal engineering

Project 1. Tornados and other rotating buoyant plumes

Supervisor:      Prof. Peter Nielsen p.nielsen@uq.edu.au

Type of project:      Experimental and numerical modelling for 1-2 students

Further details of project can be found here

 

Project 2. Differential Diffusion in wave boudary layers

Supervisor:      Prof. Peter Nielsen p.nielsen@uq.edu.au

Please see Prof. Nielsen for project details

 

Project 3. Flow Slides

Supervisor:      Prof. Peter Nielsen p.nielsen@uq.edu.au

Flow slides (known from the media as 'sink holes') which have occurred famously at Inskip Point near Fraser Island where some caravans were lost in 2016. They involve a special failure mode where a well compacted sand body can erode with a retreating vertical face up to 7metres high under water. The project involves experimental investigations of this phenomenon in the laboratory and in the field.

Please contact Prof Peter Nielsen for further details.

 

Project 4. Experimental and numercial modelling of mixing at a density interface

Supervisor:      Prof. Peter Nielsen p.nielsen@uq.edu.au (Experimental) and Dr. David Callaghan dave.callaghan@uq.edu.au (Numerical)

Set up, in the hydraulics lab, experiments similar to what we have observed during field work in the Manihiki atoll, Cook Islands.
That is, a tank is initially set up with salinity and hence density linearly increasing downwards.
A steady flow across the top is then imposed and the density profile will change from linear to having a sharp step.
Quantify the process by conductivity measurements and make a video.
Try to mimic the process with a numerical model.
Make comparisons between the small scale model results and the field data from Manihiki.
A team of two students is optimal, one focusing on the physical setup and measurements the other on numerics.

A similar student project is described in https://www.whoi.edu/fileserver.do?id=136806&pt=10&p=85893

Please contact Prof Peter Nielsen for further details.

 

Project 5. Shear stresses on sand beds under waves

Supervisor:      Prof. Peter Nielsen p.nielsen@uq.edu.au

Analysing measurements eg those of Löfquist, K E B (1986): Drag on naturally rippled beds under oscillatory flows. Misc Paper CERC-86-13, U S Army Corps of Engineers, 121pp.
And discuss the implications for wave energy dissipation and sediment transport.
A major outcome would be to show the readership, how wrong it is, to assume that bed shear stresses on rippled bed under waves vary simply as the free stream velocity or as this velocity squared.

Project 6. Propagation of dam break waves onto rough beds covered by a small initial water depth

Supervisor:      Prof. Peter Nielsen p.nielsen@uq.edu.au

It is well known that a bit of initial water, depth Di, in front of a dam break wave tends to slow down the wave propagation if the bed is smooth or if Di>>Ks, where Ks is the bed roughness.
Natural river beds below dams are however generally quite rough and initial experiments show that a bit of water, up to a couple of roughness heights have the opposite effect compared with smooth beds. I e: a bit of initial water 0 < Di <~ Ks tends to speed up the wave propagation.
This study will be experimental in the Hydraulics lab, investigating how the two opposite trends are reconciled through the experimental gap 1 < Di/Ks <5.