Study On Full Time Domain Failure Behavior Of Internal Explosion In Vertical Dome Storage Tank And Coupling Response Of Tank Group

The storage tank is an important fossil energy storage equipment.The combustible gas emitted by the storage medium in the tank will burn and explode under the action of an accidental ignition source,and the resulting tank structure damage accidents occur from time to time.The explosion shock wave,radiation heat and explosion debris formed by the explosion of the storage tank will not only cause the damage of the storage tank itself,but also pose a threat to the safe operation of the adjacent storage tank.Therefore,the response of the tank group caused by the internal explosion of the storage tank is a key technical problem for the safe operation of the storage tank.Therefore,in this paper,the two modes of internal explosion of combustible gas in the tank : detonation and detonation loads are calculated,the plastic and brittle failure conditions of the tank under different load forms are established,and the theoretical and numerical analysis methods of the tank failure in the whole time domain process of internal explosion and the response of adjacent tanks are studied,which has important academic value and good application prospect.Based on the logical relationship of solving key scientific problems,the following work has been done :Firstly,taking the vertical vault storage tank as the research object,the deflagration process of combustible gas in the storage tank was analyzed,and the calculation method of volume change of combustible gas combustion process in the tank was obtained.By considering the radiation heat transfer process between the deflagration energy of combustible gas and the tank,the Newton-Raphson iterative calculation method was used to calculate the combustion temperature,flame propagation velocity and gas overpressure in the tank,and the temperature and pressure load calculation method of deflagration of combustible gas in the tank was obtained.The numerical simulation method was used to calculate the temperature and pressure of combustible gas deflagration in a spherical vessel considering radiation heat transfer,and the calculation results were compared with the experimental data to verify the correctness of the calculation method for the temperature and pressure of combustible gas deflagration considering radiation heat transfer established in this paper.Secondly,based on the equilibrium conditions of the fluid-solid coupling interface of energy conservation,load balance and displacement coordination,the transfer calculation method of the matching grid of the physical parameters of the coupling interface in the deflagration process of combustible gas in the tank is proposed,and the boundary tracking algorithm of the coupling interface in the fluid domain inside and outside the tank caused by the deformation of the tank structure in the explicit dynamic process of internal explosion is established.The convergence criterion and calculation process of the transfer iteration for solving the parameters of the tank structure and the fluid coupling interface inside and outside the tank are obtained.The coupling interface load and structural response law of flammable gas deflagration in the tank were studied through experiments,and the multi-field coupling numerical model of tank deflagration was established.Through the comparative analysis of numerical simulation results and experimental test data,the accuracy of the calculation results of tank structural response and coupling interface load transfer based on domain solving in this paper was verified.Thirdly,the fracture failure process of tank material under deflagration condition was analyzed.According to the fracture viscoplastic failure condition of storage tank material,the shear damage criterion containing heat at the fracture tip of storage tank material was established by introducing the condition of heat flow change at the fracture tip of storage tank material.By deducing the reconstruction method of the node position of the fluid-solid coupling interface in the failure process of the tank structure domain,the load transfer calculation method of the non-matching grid of the fluid-solid coupling interface containing the tank structure missing is established,and the load transfer time advancing algorithm of the tank explosion coupling interface missing is obtained.The multi-field coupling numerical model considering the internal and external fluid domain,the storage tank domain and the adjacent storage tank was established by numerical simulation,and the fracture failure of the storage tank structure and the response of the adjacent storage tank in the whole time domain of gas deflagration in the tank were analyzed.Fourthly,the process of combustible gas from deflagration to detonation is analyzed,and the similarities and differences between the two calculation methods of gas deflagration and detonation in the same tank are compared and analyzed.Then,based on the energy release condition of flammable gas detonation in the tank,the cohesive force condition of brittle fracture failure of the tank material is established by inserting a bonding element between the nodes of the tank unit,and the equation of the ejection distance and motion trajectory of the debris formed after the tank failure is derived.Finally,the multi-field coupling numerical model of tank detonation is established,and the tank failure and debris ejection trajectory in the process of gas detonation are studied.The debris formed by detonation is compared with Monte Carlo calculation method to verify the accuracy of the multi-field coupling calculation model of brittle fracture of tank materials.Finally,considering the fluid properties inside and outside the tank,the structure of internal explosion tank and adjacent tank,a multi-field coupling calculation model of tank detonation based on TNT equivalent method is established.Through the full time domain process analysis of different liquid level height and different volume storage tanks under the condition of gas detonation in the tank,the response of explosion fragmentation in the tank and adjacent storage tanks under the action of explosion shock wave overpressure and explosion debris is obtained.By comparing the influencing factors of different flammable gas explosion conditions and processes in the tank,the failure behavior description of the tank structure under different load conditions is finally realized,and the multi-body coupling response behavior of the tank failure mechanism and the adjacent tank in the whole time domain of internal explosion is revealed.The research results of this paper can provide an important theoretical basis and calculation method for analyzing the causes of tank internal explosion accidents,preventing and controlling such industrial disasters,design and tank spacing arrangement.