Research Of Total Flooding High Pressure Water Mist System For Semi-submersible Support Platform Engine Room

The deep-water semi-submersible platform is a platform providing life and entertainment for the offshore oil rig workers.The engine room is the power place of the platform and is a high-risk area for fire.If a fire broke out,it would cause great damage.As an alternative to Halon fire extinguishing agent,water mist has been widely used in engine room fire extinguishing systems.The total submergence high pressure water mist system has high fire extinguishing efficiency,but at present there is almost no self-developed system in China It is necessary to develop a total flooding high pressure water mist system with independent intellectual property rights.In this paper,the engine room of a deep-water semi-submersible support platform is taken as the research object,and a simplified formula of the interaction between the total flooding high-pressure water mist system and the most frequent obstacle pool fire and non-obstacle pool fire in the engine room is derived The optimum diameter of water mist particles and the system flow rate are calculated according to the derived formula,which can be used to design the fully submerged high pressure water mist system in the cabin.The full-scale fire-extinguishing experiment is carried out to verify the fire-extinguishing effectiveness of the self-developed total flooding high-pressure water mist system But for the small power obstacle pool fire extinguishing time is relatively long,the analysis of the fire extinguishing experiment phenomenon shows that the system can effectively reduce the environment temperature in the cabin,making the environment temperature distribution according to uniform,but the effect of improving the gas quality in the environment is not good.Through numerical simulation,the effect of the ventilation in the obstacle shelter space on the fire suppression in the obstacle pool is studied.It is found that when the ventilation speed is more than 3.0 m/s,the fire suppression time is shorter with the increase of the air speed through comparison,it is found that when the ventilation speed is 5.0 m/s,the fire extinguishing performance can be improved effectively and the relative larger wind speed is more economical and the ventilation will not reduce the performance of putting out the non-barrier pool fire.