intro story Coast / Estuary

Coast / Estuary

Coastal systems are among the most dynamic physical systems on earth and are subject to a large variety of forces. The morphodynamic changes occurring to coastlines worldwide are of great interest and importance. These changes occur as a result of the erosion of sediments, its subsequent transport as bed load or suspended load, and eventual deposition. 
 
Estuaries are partly enclosed water bodies that have an open connection to the coast. Estuaries generally have one or more branching channels, intertidal mudflats and/or salt marshes. Intertidal areas are of high ecological importance and trap sediments (sands, silts, clays and organic matter).
Within the Delft3D modelling package a large variation of coastal and estuarine physical and chemical processes can be simulated. These include waves, tidal propagation, wind- or wave-induced water level setup, flow induced by salinity or temperature gradients, sand and mud transport, water quality and changing bathymetry (morphology). Delft3D can also be used operationally e.g. storm, surge and algal bloom forecasting. 
 
On this discussion page you can post questions, research discussions or just share your experience about modelling coastal and/or estuarine systems with Delft3D FM. 
 

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Sub groups
D-Flow Flexible Mesh
DELWAQ
Cohesive sediments & muddy systems

 

 

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Graduation Thesis on local scour around bridge's pier

U
Andrea Battisti, modified 8 Years ago.

Graduation Thesis on local scour around bridge's pier

Dear guys,

I'm an engineering student at the "La Sapienza" university of Rome. For my graduation thesis I'm trying to use Delft3D in order to study the hydrodynamic field and morphodynamic evolution around the bridge's pier in a 3D simulation. It's my first experience with a Computational Fluid Dynamics modelling framework, so I'm not an expert.
Until now I have made some attempts in order to understand how to use Delft3D and how to set up the parameters in Flow-GUI. Now I'm trying to realize a straigth channel with a bridge's pier in the middle, in order to analyze the hydrodynamic and morphodynamic changes the pier produces. My problem is: how can I create the pier? I have read the Flow User Manual, but I haven't understand the correct method to realize a cylindrical pier. Until now I have simulated the hydraulic structure by means of the "Dry Points" command, but I think it's not the best way to simulate local scour, because "Dry Points" is not a structure, but only a dry cell. Moreover it has not a cylindrical shape, but it is a square monopile.
I hope someone can help me, explaining step by step the correct method to draw a pier in a channel and suggesting me scientific publication or Thesis to read.
Thanks to all for your attention.

Best regards,


Andrea Battisti
Mohamed Yossef, modified 8 Years ago.

RE: Graduation Thesis on local scour around bridge's pier (Answer)

Youngling Posts: 23 Join Date: 2/23/11 Recent Posts
Dear Andrea

To simulate the oscillation of the separation points along the edge of a round pillar, you would need to use a boundary-fitted circular grid. However, a circular grid is not possible in Delft3D. Using a high resolution square grid with the pillar represented using dry cells is the best approximation that Delft3D offers.

Good luck
Mohamed Yossef
U
Andrea Battisti, modified 8 Years ago.

RE: Graduation Thesis on local scour around bridge's pier

Dear Mohamed,

thank you for helping me!
For my Master Thesis I have represented the pier as you suggested.
Now I'm continuing to study the user manual and to improve my model in order to check every possible manner to analize the local scour and hydrodynamic around the pier.

Kind regards,

Andrea Battisti
U
Nima Attari, modified 5 Years ago.

RE: Graduation Thesis on local scour around bridge's pier

Hi, my thesis is about modeling of local scour around circular bridge pier


Is there any way in delft3D to change the formulation that is used in calculating Bed Shear Stress?

I want to calculate Tb (bed shear stress) with using Shear Velocity (u*) ------> Tb = (row) x u* ^ 2 (row = density)

AND

I want to calculate u* (shear velocity) with using Kb (turbulent energy at bed level which is calculated with k-e model) ------> u* ^ 2 = Kb / SQRT(Cmoo) Cmoo = constant = 0.09


Thanks

Attachments:

GW
Grant Wilson, modified 1 Year ago.

RE: Graduation Thesis on local scour around bridge's pier

Youngling Posts: 7 Join Date: 11/7/19 Recent Posts
Andrea Battisti:

Dear guys,

I'm an engineering student at the "La Sapienza" university of Rome. For my graduation thesis I'm trying to find an essay writer for hire and use Delft3D in order to study the hydrodynamic field and morphodynamic evolution around the bridge's pier in a 3D simulation. It's my first experience with a Computational Fluid Dynamics modelling framework, so I'm not an expert.
Until now I have made some attempts in order to understand how to use Delft3D and how to set up the parameters in Flow-GUI. Now I'm trying to realize a straigth channel with a bridge's pier in the middle, in order to analyze the hydrodynamic and morphodynamic changes the pier produces. My problem is: how can I create the pier? I have read the Flow User Manual, but I haven't understand the correct method to realize a cylindrical pier. Until now I have simulated the hydraulic structure by means of the "Dry Points" command, but I think it's not the best way to simulate local scour, because "Dry Points" is not a structure, but only a dry cell. Moreover it has not a cylindrical shape, but it is a square monopile.
I hope someone can help me, explaining step by step the correct method to draw a pier in a channel and suggesting me scientific publication or Thesis to read.
Thanks to all for your attention.

Best regards,


Andrea Battisti

Hello Andrea,
You can check the pdf documents from the University of Windsor library. One of the possible papers you may refer to is Effect of suction on local scour around circularbridge piers. Or here's the older reference: Local  scour  at  bridge  piers  in  non-uniform  sediment” from  the University of Auckland, at Auckland. Many more: http://etd.lib.metu.edu.tr/upload/12615594/index.pdf
Dr. Grant Wilson