| The thesis puts forward a process of decomposition analysis for urea reactor explosion that depends on plywood wrapped type urea tower detonation process which launched simulation analysis. In order to build analysis model this paper thkes DN1400 urea tower as study object. The urea tower explosion is caused by stress corrosion crack flaw, when the crack reaches to dehiscence limit, it splits open from the crack tip. With the crack growth, load on the remaining cylinder wall increases, and when it reaches to the yeild limit, cylinder rupture is taken place. After fracture, material unbalance in the reactor lead to bump phenomenon and phase transition, gas phase condensate proliferation and form the explosive shock wave. The thesis simulates the shock wave about speed flow and pressure flow two parts. Determining the space model according to influence sphere of TNT equivalent method and using CFD software package mixture model and VOF model to research, and based on the obtained results adopt superposition principle to solve the distribution of blast flow field. There is a certain reaction to tower for pressure increasing, resulting in intermediate tower deformed under pressure, therefore, using ANSYS software to analyze structural shape variables and obtain the rolled state when exploded, finally outstripped. After the top section is separated from the compartment, which is pulled off under the pressure boost lagging far behind the scene, and the fracture section would produce a certain deformation. The tower body lower segment will remain in place. Finally, the fracture mechanism is determined according to stress analysis. Utilizing the finite element software to do a form of urea tower explosion simulation study and achieve a better analysis results, the disquisition has some reference value to vessels explosion process simulation.
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