Nonlinear fluid-structure interaction calculation of the leakage behaviour of cracked concrete walls

In the case of severe accidents in nuclear power plants, containments are the last barrier to prevent the release of environmentally hazardous substances. Therefore, the leaktightness of the containment is of decisive importance for the safety and protection of the environment in case of an accident. A numerical model based on the Finite Element Method has been developed to calculate the leakage behaviour of reinforced concrete walls. Leakage flow and structural response are solved iteratively. For the calculation of the leakage flow a fluid model has been used which takes into account the condensation of the steam part within the air-steam mixture. Both, the release of the latent heat in the case of condensation and the following two-phase flow of air and water have been considered, too. Tests with the SIMIBE Experimental facility [Caroli, C., Coulon, N., Renson, C., 1995. Steam leakage through concrete cracks: parametric study with SIMIBE experiment and interpretation of the results. Tech. Rep. Commissariat A L’Energie Atomique (CEA)] are used for verification of the condensation and two-phase flow models.