The synthesis of sound of church bells by means of dynamic finite element analyses

In the frame of the PROBELL (Maintenance and Protection of Bells) European Project, the University of Padova developed a methodology to synthesize the sound of a bell starting from its drawing. The proposed method is based on a physically based approach, which requires the knowledge of the bell partial frequencies and their modal weights. This set of parameters is extracted from the bell profile through dynamic finite element analysis. In this paper, the finite element analyses performed to extract the required parameters are described, starting from the wooden gauge adopted from the bell founders up to the determination of the partial frequencies. Then the FE results are successfully compared with those experimentally measured on 5 bells cast by the Fonderia Colbachini. Finally, the influence of the actual bell geometry on synthesized sound is analyzed by applying the reverse engineering approach on one of Colbachini’s bells.