Particle depletion in an enclosure with turbulent natural convection was investigated using severe accident code MELCOR 2.1. A model of the experimental DIANA facility was created and the results of the simulation were compared against the experimental and LES data from earlier work. Three particle sizes 0.5 ?m, 1.0 ?m and 2.5 ?m were used in the study. The temperature difference between the vertical isothermal walls of the enclosure was varied between 40 K, 20 K and 10 K. The MELCOR model reproduced the stratified temperature field and the encircling natural convective flow in the cavity qualitatively. The deposition rate was well matched between the MELCOR and experimental data, but further analysis indicated that the thermophoresis was overestimated in the MELCOR modeling, thus compensating for the turbulent deposition, which was not considered in this MELCOR simulation work.