Development of DETAC and its application to the hydrogen detonation analysis

In this study, a numerical analysis code (DETAC, Detonation Analysis Code) for hydrogen detonation during the reactor severe accident was developed using Fortran 90 language, and the simulation was performed for the hydrogen detonation. A global-chemistry model was adopted to simulate the chemical reaction. The Euler equations were solved using third-order Runge-Kutta method with fifth-order weighted essentially non-oscillatory scheme handling the convection flux. Afterward, the hydrodynamics solver was verified by comparison of predicted results and exact solutions of four cases of shock tube problems. A hydrogen detonation in a pipe was simulated to verify this code by comparing the results with the classical C-J theory. Furthermore, this code was applied to the hydrogen detonation analysis in the compartment of BWR building. Two cases with different ignition locations were analyzed in this paper and the maximum pressure of these cases were 7.5 MPa and 8.0 MPa, respectively. The pressure and the temperature during detonation were affected by the ignition location. The results indicated that the possibility of reactor building destruction exists if the hydrogen detonation occurs.