A New Methodology Based On Infrared Thermography And Numerical Modelling For The Conservation Of Historical Buildings

The indoor microclimate is very often the main hazard for the conservation of heritage buildings, including decorations such as wall and wood paintings. In many cases heating devices are requested inside the historical buildings, but it is difficult to forecast the long term effect of a conditioned microclimate on precious works of art. Generally, measures for safeguarding the historical buildings take into account information about indoor environmental conditions. These are usually collected through long term monitoring of the air temperature and relative humidity, coupled to visual inspection and photographic recording. For more advanced surveys infrared thermography can be applied thanks to its contactless and non-invasive nature. The proposed approach is to couple infrared thermography monitoring with Computational Fluid Dynamics modelling. This methodology consists in two steps: at first a building survey using a Quantitative infrared thermography technique followed by a modelling of different Heating, Ventilating and Air Conditioning solutions. An additional step could be added after a retrofit intervention, in order to verify the efficiency of the selected solution. The main advantage of numerical simulations is the possibility to calculate the indoor parameters in a large number of internal points. The aim of this work is to set up an investigation method allowing the prediction of the best indoor conditions for the preservation of the frescos and the correct utilization of the air conditioning systems. This work presents the results of the proposed method applied to a small church (San Biagio di Baver, in the North-East of Italy) with a precious medieval fresco paintings. Thermographic survey was performed by the aIRview system that acquired simultaneously different microclimatic parameters (such as air temperature, wall temperature, relative humidity). The obtained data were used as a basis for the Computational Fluid Dynamics modelling. This leads to an accurate design and comparison of different retrofit interventions.