Bubbles 2
BUBBLE CURTAINS FOR NOISE MITIGATION
Initiative
The Bubbles 2 JIP will focus on the operational use of bubble screens and understanding their working principles in various operational situations and how to use them more effective and energy efficient. Bubbles 2 is the follow-up project of the Bubbles JIP.
background
During installation of monopiles and jackets at sea the noise generated by high energy pilling may harm the marine environment. There are different methods to reduce these noise levels. One of these mitigation methods is the use of bubble curtains. These bubble curtains are generated by using a loop hose on the seabed, pressurised by air compressors on a support vessel, enclosing the pile driving location. Although proven to be effective, improvements can be made in the preduction of the sound dampening and efficiency to reduce costs and energy use by the air compressors. To make these improvements, more understanding of the sound dampening working principle of bubble screens is required by the industry.
Bubbles 2 is the follow-up project of the Bubbles JIP executed from 2020 until 2023. This Joint Industry Project aimed at achieving more efficient and effective use of bubble curtains for noise mitigation in offshore installation projects. During the JIP, research was done to get a better fundamental understanding and engineering of bubble screen use within specific projects, to control noise levels.
In Bubbles 2, the focus will be on the operational use of bubble screens and understanding their working principles in various operational situations and how to use them more effective and energy efficient.
Bubbles 2 is the follow-up project of the Bubbles JIP executed from 2020 until 2023. This Joint Industry Project aimed at achieving more efficient and effective use of bubble curtains for noise mitigation in offshore installation projects. During the JIP, research was done to get a better fundamental understanding and engineering of bubble screen use within specific projects, to control noise levels.
In Bubbles 2, the focus will be on the operational use of bubble screens and understanding their working principles in various operational situations and how to use them more effective and energy efficient.
Problem definition
In practice sound dampening often deviates from prediction models leading to delays in the pile driving operation. This deviation often is mitigated by installing extra bubble screens with corresponding extra costs and energy use.
Contact
Tobias van Dijk
Project Manager
Jeroen den Hollander
Project Manager
Project proposal
The initial Bubbles JIP aimed at fundamental research. In this follow-up project MARIN, together with partners from the industry, universities and research institutes, will focus more on the operational side of bubble screens: how to increase their effectiveness and energy efficiency.The proposed scope of work consists of six work packages:
WP1: (literature) Study of current status in the areas of
- rules and regulations
- bubble curtain experiments
- bubble curtain techniques
- pile driving techniques (sound source)
WP2: Analysis of experiment data Bubbles JIP (medium scale experiments at end of JIP)
WP3: Bubble hose/ nozzle technique development
WP4: New medium scale/full scale experiments and analysis of data of those experiments
- scope of experiments dictated by WP1, WP2 and WP3 together with needs from numerical simulations and operations
WP5: Improve numerical simulations based on new data/ insights
- prediction of sound dampening per installation project/area
- including aspects of soil, current and knowledge on sound propagation through water
WP6: Best practice and recommendations on the use of bubble curtains as sound mitigation
- measurements during pile driving operations
Planning
The project is intended to start Q4 2024 and is expected to have a duration of 3 years.Currently the Bubbles 2 project is still open for new partners to join and discuss the final scope of work.
A double bubble curtain is deployed around heavy lift installation vessel Svanen (Picture: Van Oord).