Final Report Summary - FLOODSTAND (Integrated Flooding Control and Standard for Stability and Crises Management)
Executive Summary:
A crucial question related to any passenger ship in crisis concerns the safety and the risk involved. As the size of the new ships has increased remarkably during the past decades, these issues have become even more important. When a larger number of passengers get onboard the same vessel the risk to life increases, and hence new insights and methods to deal with it need to be explored. As it is known that the major risk to persons onboard is posed by the hazard of flooding, project FLOODSTAND was planned to respond to this need by deriving new detailed, more reliable information and modeling principles on the process of ship flooding and by developing new methods for analysing the flooding extent onboard and by developing a standard for a more comprehensive measure of damaged ship stability than standards in use today.
In passenger ships, the non-watertight subdivision in the watertight compartments is usually rather dense. Consequently, the structures involved will have a large effect on the progress of the floodwater in the event of breach and leakage. Until now, there has not been available reliable data for assessing the response and strength of widely used structures (such as fire doors) under the pressure of floodwater. However, in flooding simulation, it is necessary to include also the leakage through closed doors since the simulated time-to-flood depends heavily on the applied model for the leakage. Through various analyses carried out in FLOODSTAND the modeling of the flow through typical doors stands now on a much more reliable basis than before. With the new data and guidelines prepared the flooding simulations can serve the needs of designers and operators better than before.
Since the flooding simulations usually require a long time for computing, simplified approaches for calculations, e.g. for modeling the flows inside the damaged ship or for the further assessment of the status of the vessel are often favored. The applied methods have been validated with experiments. This approach is used in all flooding simulation tools. Experimental discharge coefficients that take into account the pressure losses in the openings have widened and deepened the knowledge and understanding related to proper values for discharge coefficients. They are now better known for various typical openings and structures in a modern passenger ship.
Little knowledge has been available with respect to the survivability of damaged cruise ships at calm water and in waves. Some interesting efforts towards this research area have now been directed in FLOODSTAND. These efforts have increased the knowledge and understanding of the related phenomena and the outcome, although in practice it may still be a challenging effort to model a whole ship with every detail.
FLOODSTAND was set out to derive missing data for flooding simulations, for the validation of time-domain numerical tools for the assessment of ship survivability, rescue and to develop guidelines as well as a standard for a comprehensive measure of damaged ship stability, addressing the risk of flooding in passenger ships, cruise liners and ROPAX-vessels. The project has reached these goals fairly well.
Guidelines and uncertainty bounds have been established, and many simulations for assessing the damage and extent of flooding onboard a damaged ship or assessments of the time-to-capsize have been carried out. FLOODSTAND also aimed at establishing methods for instantaneous classification of the severity of ship flooding casualty with an expected performance in reaching the related objectives.
FLOODSTAND will contribute in reducing the risk to human life, by ensuring that the level of safety of the transport system will respond to the increasing demand, featured by large passenger ships. Prospects for this development look encouraging, based on the results achieved during the course of the project. The impact of FLOODSTAND is notable and it will most probably grow considerably with time.
Project Context and Objectives:
see attachment
Project Results:
see attachment
Potential Impact:
see attachment
List of Websites:
http://floodstand.aalto.fi
http://floodstand.aalto.fi/Participants/contact_1.html
A crucial question related to any passenger ship in crisis concerns the safety and the risk involved. As the size of the new ships has increased remarkably during the past decades, these issues have become even more important. When a larger number of passengers get onboard the same vessel the risk to life increases, and hence new insights and methods to deal with it need to be explored. As it is known that the major risk to persons onboard is posed by the hazard of flooding, project FLOODSTAND was planned to respond to this need by deriving new detailed, more reliable information and modeling principles on the process of ship flooding and by developing new methods for analysing the flooding extent onboard and by developing a standard for a more comprehensive measure of damaged ship stability than standards in use today.
In passenger ships, the non-watertight subdivision in the watertight compartments is usually rather dense. Consequently, the structures involved will have a large effect on the progress of the floodwater in the event of breach and leakage. Until now, there has not been available reliable data for assessing the response and strength of widely used structures (such as fire doors) under the pressure of floodwater. However, in flooding simulation, it is necessary to include also the leakage through closed doors since the simulated time-to-flood depends heavily on the applied model for the leakage. Through various analyses carried out in FLOODSTAND the modeling of the flow through typical doors stands now on a much more reliable basis than before. With the new data and guidelines prepared the flooding simulations can serve the needs of designers and operators better than before.
Since the flooding simulations usually require a long time for computing, simplified approaches for calculations, e.g. for modeling the flows inside the damaged ship or for the further assessment of the status of the vessel are often favored. The applied methods have been validated with experiments. This approach is used in all flooding simulation tools. Experimental discharge coefficients that take into account the pressure losses in the openings have widened and deepened the knowledge and understanding related to proper values for discharge coefficients. They are now better known for various typical openings and structures in a modern passenger ship.
Little knowledge has been available with respect to the survivability of damaged cruise ships at calm water and in waves. Some interesting efforts towards this research area have now been directed in FLOODSTAND. These efforts have increased the knowledge and understanding of the related phenomena and the outcome, although in practice it may still be a challenging effort to model a whole ship with every detail.
FLOODSTAND was set out to derive missing data for flooding simulations, for the validation of time-domain numerical tools for the assessment of ship survivability, rescue and to develop guidelines as well as a standard for a comprehensive measure of damaged ship stability, addressing the risk of flooding in passenger ships, cruise liners and ROPAX-vessels. The project has reached these goals fairly well.
Guidelines and uncertainty bounds have been established, and many simulations for assessing the damage and extent of flooding onboard a damaged ship or assessments of the time-to-capsize have been carried out. FLOODSTAND also aimed at establishing methods for instantaneous classification of the severity of ship flooding casualty with an expected performance in reaching the related objectives.
FLOODSTAND will contribute in reducing the risk to human life, by ensuring that the level of safety of the transport system will respond to the increasing demand, featured by large passenger ships. Prospects for this development look encouraging, based on the results achieved during the course of the project. The impact of FLOODSTAND is notable and it will most probably grow considerably with time.
Project Context and Objectives:
see attachment
Project Results:
see attachment
Potential Impact:
see attachment
List of Websites:
http://floodstand.aalto.fi
http://floodstand.aalto.fi/Participants/contact_1.html
