For the evaluation of thermal consequences of a sodium leak accident in the auxiliary buildings of the LMFBRs, the sodium pool combustion codes SOFIRE-MII, ASSCOPS and SPM have been developed. In SOFIRE-MII and ASSCOPS, assumptions are made that the combustion occurs at a pool surface, and the process is controlled solely by the turbulent oxygen transfer from atmospheric gas to the pool surface. Combustion heat is dissipated by turbulent and radiation heat transfers to the gas and surrounding walls. On the contrary, a flame over the pool is modeled in SPM, in which the combustion is controlled by sodium vapor and oxygen supplies by the diffusion from the pool surface and the turbulent mass transfer from the atmospheric gas, respectively. These codes were validated using experimental results obtained in the large-scale sodium fire test facilities; SAPFIRE (PNC, Japan) and FAUNA (KfK, Federal Republic of Germany). The comparison revealed that agreements between the codes and the test results are reasonably well.
