The explosion process of urea reactor was studied. In order to investigate the shock wave formation and the characteristics of its propagation, the explosion of gas phase in the top regime of urea reactor was simulated numerically. Based on the simulation of shock wave propagation in the liquid phase, the shock wave velocity was obtained. The superposition point and the superimposed pressure for the shock wave in the liquid phase were determined by considering the propagation velocity and time difference of entering the liquid for the shock wave. The results showed that the shock wave pressure increased significantly after superposition, and the pressure was high enough to break the reactor at that point. The super high temperature liquid gasified and released out quickly, resulting in more hazardous secondary explosion.
