CFD Analysis and Risk Management Approach for the Long-Term Prediction of Marble Erosion by Particles Impingement

Abstract

A preliminary study, performed by using a CFD (Computational Fluid Dynamic) analysis, on the erosion of a marble surface generated by particles impingement from air pollutants in indoor or outdoor environments, is presented. To describe the methodology, a very conservative simulation, at low air velocities and particle concentrations, has been carried out by using a commercial CFD computer program, in order to estimate the effect of a long term exposure to this aggressive phenomenon. The Eulerian-Lagrangian approach is used to simulate the gas-solid two-phase flow while semi-empirical model is used to calculate the erosion rate. The case study refers to typical conditions that could occur in an indoor environment, as a museum, but the methodology could be also successfully applied to marble surfaces exposed to the outdoor environment. The marble mass loss due to erosion from impinging particles has been estimated by using results from the CFD analyses and, following the Risk Management approach, the maximum particles concentration giving visible effects in a period of 100 years, for different air velocities and a typical particle distribution of diameters, has been evaluated. The results, obtained using a very conservative model, show that, in the present case study, the detrimental effects on marble surfaces can be controlled and considered negligible.