Computational fluid dynamics (CFD) modeling of microclimate forsalts crystallization control and artworks conservation

Many deterioration processes are linked to unsuitable microclimatic condition in cultural buildings.One of the most diffused processes is soluble salts crystallization that can be accelerated in masonry structures within specific microclimatic values for different chemical compounds. In this paper, micro-climate and efflorescence diffusion were monitored over a one-year period in the Crypt of the Cathedralof Lecce (South Italy). This allowed to relate the microclimate with the efflorescence variation overtime. A three-dimensional computational fluid dynamics (CFD) model was then developed to detail thethermo-hygrometric parameters and airflow patterns responsible for salts crystallization and artworksdeterioration. Two main conditions were reproduced; one to simulate the current microclimate, whichsimulations showed to be inadequate for conservation, and the other to search for a more appropriatesolution. In both cases, summer and winter conditions were simulated and compared to find a microcli-mate able to ensure more suitable thermo-hygrometric intervals required by the constituting artworksmaterials. The results helped to suggest actions to improve maintenance of the Crypt.