Preserving Leonardo's Last Supper: A CFD case study

Computational Fluid Dynamics was used to assess the effectiveness of heating the surface of the Last Supper to preserve the masterpiece from PM10 deposition as well as to investigate the consequences of increasing the number of visitors simultaneously admitted in the room. For this purpose, the flow of moist air in the Refectory of “Santa Maria delle Grazie” in Milan was numerically simulated. In addition, the trajectories of the PM10 particles emitted by visitors were traced and their concentration monitored, the latter considered one of the main parameters possibly harmful to the painting. Moreover a velocity deposition model was applied to evaluate the soiling hazard through a dose-response function. It was found that, even doubling the number of visitors, no perceptible blackening of the surface of the Last Supper can be foreseen also in the far future.