Numerical Simulation Of Automatic Sprinkler Suppression Fire In High-Rack Warehouse Based On FDS

With the continuous improvement of our country’s economic aggregate,the economic aggregate ranks second in the world.The rapid increase in social wealth,coupled with the rapid development of the domestic logistics industry,has made warehousing construction in the ascendant in my country.As the high-rack warehouse fire is a three-dimensional fire,once the warehouse fires,it will cause huge loss of life and property,so it is of great significance to the research of warehouse fire sprinklers.The warehouse fire test is a very destructive test,and when it comes to automatic sprinkler systems,it will cost a lot of manpower,material resources,and financial resources.As a result,there are fewer fire test studies related to high-bay warehouses.The engineering parameters used in the specifications and manuals are only predicted by a small number of tests or based on the Critical Delivered Flux(CDF)measurement results,and there is no large amount of test data as support.With the improvement of computer computing power and the development of computer fluid dynamics(CFD),CFD models can describe fires with complex geometric shapes.Therefore,it is economical and cutting-edge to use fire dynamics simulation software to conduct self-realistic combustion simulation simulation research on warehouses.(1)Research on physical fire and combustion tests of warehouse-related real items.Based on the principles of quality and energy conservation,FDS(Fire dynamics simulator)is used to simulate real items of common warehouse materials such as polyurethane foam chairs and standard combustors,and compare heat release.The error of the peak value of the velocity curve,the time to reach the peak value and the total heat of combustion are all within 10%,which proves that the built model can completely replace the fire test,and a real object simulation model that can be used for parameter design research is established.(2)FDS is used to build a real simulation model for the five storeyed shelf warehouse.Through the comparison and analysis with the results of sprinkler action temperature curve and the number of burned items in the real fire test of Tianjin Fire Science and Technology Research Institute,the error between the simulation results of the model and the real fire results is less than 15%,which meets the engineering requirements.It is proved that the sprinkler model can replace the real test and can be used to study the engineering parameters of sprinkler system in warehouse.(3)Explore the fire extinguishing effects of ESFR sprinklers at different sprinkler density,and analyze the effects of fire on warehouse steel structures and target shelves under various working conditions.The results show that the fire suppression can not be realized when the sprinkler density is less than 33L/(min·m~2)when the warehouse clearance height is 9m and the shelf height is 7.5m.And the automatic water spray system can better prevent damage to the warehouse steel structure.Finally,reasonable engineering design parameters are proposed:when the warehouse storage is boxed non-foamed plastic,the maximum clearance is 9m,and the maximum storage height is 7.5m.When using ESFR Sprinklers,the water spray intensity should not be less than 33L/(min﹒m~2).Provide relevant technical support for the revision of the specification and the physical combustion test.