Progress in Offshore Research at TUD
Description
Progress in Offshore Research at Delft University of Technology (TU Delft).
This evening KIVI NIRIA will offer the floor to two PhD students to present their work, which is to lead to a PhD thesis.
*Underwater noise from offshore pile driving by Apostolos Tsouvalas
The generated levels of underwater noise from pile driving during the construction of large offshore wind farms are unacceptably high according to upcoming regulations. This results in serious delays and increased costs for the offshore wind industry since the pile driving activities have to be conducted at specific times during the year.
During offshore pile driving, a hydraulic hammer hits the top of the pile and a stress wave is generated which propagates downwards. Part of the energy introduced into the system is spent on the pile progression into the soil whereas another part is irradiated into the water in the form of pressure waves from the vibrating surface of the shell. A third part of the energy enters the soil and generates elastic waves which propagate through the soil medium.
The primary goal of this project is to understand and analyse the main sources of underwater noise generated from offshore pile driving and to test the available mitigation measures used in practice. For this reason, a new model will be developed which will include the hydraulic hammer, the monopile, the compressible viscous water and the water-saturated seabed. By doing this, we aim at providing the offshore wind industry with the necessary tools in order to predict and eventually reduce the underwater noise for a wide range of system parameters.
* Ice Induces Vibrations of Offshore Structures by Hayo Hendrikse
Occasionally bottom offshore structures experience sustained vibration due to drifting ice sheets crushing against them. These vibrations, known as Ice Induced Vibrations (IIV), may lead to fatigue problems, safety issues and uncomfortable working conditions. Two following mechanisms are believed to lead to IIV:
- The synchronisation of the frequency of the ice failure and that of the structure;
- Amplification due to a descending dependence of the compressive ice strength on the loading rate.
To date only phenomenological models exist for the prediction of ice- and structural behaviour in these situations which are not up to the standards set by the industry.
Goal: To develop a hybrid multi-scale model of a moving ice sheet dynamically interacting with a bottom founded structure.
After the break, the award for the Best Graduation Work Offshore and Dredging Engineering 2012 will be presented.
As of 2012, the Offshore Engineering Department of the Royal Institute of Engineers KIVI NIRIA has established an annual award for the best graduation work in Offshore and Dredging Engineering. The graduation prize involves €2,000
Seven candidates were nominated:
- Jeroen Brugman (Buoyancy tank connection study for the Heerema Hybrid Exchangable)
- Thijs den Hamer (Optimising for Design and Operation - Application of a Configuration Optimisation Routine to the Design and Operation of an Offshore Wind Turbine Installation Jack-Up)
- Reza Karimi (Investigation of Hydrostructural Interactions based on the results of the SLOSHEL project)
- Jan Maris (Examination of Non-Stationary records of Nonlinear Waves using Signal Processing Methods)
- Alexander van Nauta Lemke (The Bypass Dome - A New Solution for Offshore Hydrocarbon Containment)
- Richard van Rijs (Bulldozer effect in front of a draghead)
- Arnaud Verschelde (Erosion behaviour of a draghead)
On 24 May a.s., Wim Jolles will speak on behalf of the jury (which in addition to himself consists of: Jo Pinkster, Peter Tan, Jan Vugts and Wim Vlasblom) will announce which of the above candidates has been awarded the Prize for the Best Graduation Work Offshore and Dredging Technology 2012. After the presentation, the winner will give an explanation of his graduation report.
Speaker(s)
- Apostolos Tsouvalas & Hayo Hendrikse, PhD Candidates Section Structural Mechanics (Promotor: Prof.dr. A.V. Metrikine)
- winner Prize for the Best Graduation Work Offshore and Dredging Engineering 2012
PARTICIPANTS
* There will be an opportunity to join the sponsored bread meal at 18.00.
* The bread meal beforehand and the drinks afterwards will be offered by TU Delft.
* The drinks afterwards will be held in café "de Posthoorn" on the Lange Voorhout.
* You can indicate until 22 May at the latest whether you would like to participate in the sandwich meal.
* After 22 May, you can still register - as long as the maximum number of participants has not yet been reached - but no sandwich meal will be reserved for you. You will then be expected at 7pm
Location
KIVI NIRIA Building, Prinsessegracht 23
2514 AP The Hague
Organiser
Offshore Technology
Name and contact details for information
Further information at the e-mail address below.