Wind Load Response Of Marine Evacuation Inflatable Slide Under Fluid-solid Coupling Analysis

At present,the development and application of domestic marine emergency evacuation system is in the ascendant stage,the inflatable slide type emergency evacuation system has received extensive attention from researchers due to its high efficiency in evacuation and ease of installation and maintenance.The flexible inflatable membrane has a light weight,large span and high wind sensitivity.Therefore,the stability of the inflatable slide under the action of wind load and the efficiency of evacuation are becoming more and more significant in research.This paper studies the simulation of wind load response and evacuation process on the inflatable slide type evacuation system of high-speed passenger rolling ships.Firstly,the overall scheme of the inflatable slide type evacuation system is determined,and the stability of the floating body structure under the action of waves is verified;Based on the early research of inflatable membranes,the theory of fluid-solid coupling is introduced to formulate research routes;On the theoretical level,the theory of numerical simulation of wind field is established,and the fluid space and structure space are discretized;Simplified information transfer model of structure domain and fluid domain is established based on structural mechanics,and simulation boundary conditions are determined.In order to verify the rationality of the simulation process and the reliability of the results,the model wind tunnel test completed by Tokyo Technology University is checked by the example,and the result is good.Considering the actual offshore deployment conditions,the ANSYS CFX is used to simulate the wind load response under the variables of 0,30,60 and 90 degrees wind direction,15 m/s,20 m/s,25 m/s wind speed,3000 Pa,3500 Pa,4000 Pa,4500 Pa and 5000 Pa inflatable internal pressure.The displacement deformation of the inflatable slide under wind load and the wind pressure distribution near the membrane surface are obtained.According to the simulation results,the displacement and wind resistance data under various working conditions are compared to find the most dangerous condition for the evacuation system.Within the experimental internal pressure range,the influence of internal pressure on wind load response is analyzed to find the ideal internal pressure that satisfies the structural stability.For the internal pressure,the modal analysis of the slide structure is completed,and the wind vibration response result is obtained.Based on the test results of the wind load stability of the inflatable slide,the Workbench Ls-dyna module is used to simulate the inflation process of the inflatable slide to verify the rationality of the AIRBAG inflation principle.The displacement change and equivalent stress distribution under different inflatable internal pressure are compared.Then,a reasonable simplified simulation of the evacuation efficiency is carried out.The inflatable internal pressure is taken as the variable to find the rule of the influence of the personnel sliding on the bending deformation and the personnel sliding speed of the inflatable slide when the internal pressure changes,and to find the ideal internal pressure which satisfies the efficiency of the slide.The results show that the pneumatic membrane structure has a high wind sensitivity,and the 30 degree wind direction angle is the most dangerous condition.With the increase of internal pressure,the stiffness and stability of the structure are improved.The internal pressure of 4000 Pa is the ideal pressure to meet the stability requirements.As the internal pressure increases,the deformation of the slide caused by the personnel decline is reduced,the speed of the decline is improved,and the evacuation efficiency under the test range can reach the evacuation requirement.The internal pressure of 4000 Pa is the ideal internal pressure to meet the double standard of evacuation efficiency and stability.The research in this paper has practical value for the wind resistance analysis and engineering application of the inflatable slide type evacuation system.