# River

Rivers are natural water courses. They have vital contributions to the social and economical welfare of societies living along their course. They provide continuous, usually dependable, flow and supply of water. Accordingly, centralised civilisation began emerging independently along number of river valleys; e.g. the Nile, Tigris and Euphrates, the Indus and the Yellow Rivers. Since then, mankind has been in continuous struggle to understand and live in harmony with this gift/force of nature. Modelling rivers is the modern way to understand their behaviour and is an essential tool to tackle several river problems.

Delft3D is the state-of-the-art modelling framework for hydrodynamics, water quality, ecology, waves and morphology.

Here, in this space, we share knowledge & experiences, and discuss issues related to modelling of rivers.

## Message Boards

### Graduation Thesis on local scour around bridge's pier

AB

#### Graduation Thesis on local scour around bridge's pier

Youngling Posts: 5 Join Date: 10/15/12
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 7 Years ago.

Youngling Posts: 23 Join Date: 2/23/11
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
AB

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

Youngling Posts: 5 Join Date: 10/15/12
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
NA

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

Youngling Posts: 9 Join Date: 8/11/15
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:

YJ

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

Youngling Posts: 16 Join Date: 9/26/19
Andrea Battisti:

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 usa today protonmail.
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
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.
YJ

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

Youngling Posts: 16 Join Date: 9/26/19
Andrea Battisti:

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 filezilla uc browser rufus.
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
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.
GW

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

Youngling Posts: 3 Join Date: 11/7/19
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