Design And Experimental Study On Sealed Cabin Used For Life-saving From Capsized Vessels

With the prosperity of shipping,the frequency of ship accidents has also increased.Among them,capsizing is a relatively common form of ship distress.The speed of the ship's turn is faster,so the air in the cabin will form an air layer at the top.That makes the ship still floating on the water.It is a very difficult task to rescue trapped people in capsized vessels.Especially for the life rescue of steel vessels,due to the lack of special rescue tools,the rescue process has the problems of high risk and low efficiency.Therefore,this paper designs a sealed cabin suitable for the life-saving rescue from steel capsized vessels.Opening holes for rescue in sealed cabin can effectively prevent gas escaping from ships.At the same time,the sealed cabin has a pressurizing function,which can compensate the pressure difference between the inside and the outside of the cabin,thereby reducing the influence on the floating state of vessels.Focusing on the task of life salvage from tipping vessels and combining with the characteristics of rescue using the method of opening holes on bottom of ships,this paper firstly compares the overall structure scheme of rescue sealed cabin.Then the structure of each part was designed in detail,and the structure size and form were optimized based on the theoretical analysis and finite element simulation results.According to the characteristics of the structure,appropriate sealing methods have been selected.Subsequently,the characteristics of the environmental parameters in the sealed cabin were analyzed.Based on this,an automatic control scheme for pressurization,decompression and ventilation of the sealed cabin has been worked out.And a test bench was set up for performance testing and program adjustment.Finally,the weight optimization of the sealed cabin is carried out.The specific research contents of this paper are as follows:(1)The characteristics of the life-saving rescue from capsized vessels and the functional requirements of the cabin are analyzed.By comparing the advantages and disadvantages of different cabin layouts and section shapes,the overall structural scheme of the rescue cabin is determined.Then the structure and dimensions of each component were designed in detail,and the key structures were optimized.According to the structural characteristics of different positions,corresponding sealing methods are selected.(2)The strength of simple structure with large force is checked by theoretical calculation method,then the complex structure is simulated based on ANSYS Workbench,and the structure with insufficient strength is optimized according to the simulation results.(3)The environmental characteristics of rescue sealed cabin are analyzed.According to the requirements of personnel survival and safety,the objectives of monitoring and adjusting environmental parameters such as pressure,temperature,carbon dioxide concentration and oxygen concentration in the cabin are determined.The control schemes of pressurization,decompression and ventilation are determined according to these objectives.Then the data acquisition and control system is built based on Lab VIEW software.(4)The first generation salvage sealed cabin was processed and a pressure test-bed was built to simulate the fixed state of the rescue sealed cabin and the vessel.The sealing performance of the sealed cabin and the rationality of the automatic control scheme are tested.Then the parameters of the control scheme are adjusted according to the test results,(5)The structure weight was optimized by improving the structure form and material.