EXPERIMENTAL RESEARCH REGARDING THE FREE VIBRATIONS OF LIGNOCELLULOSE PLATES FROM THE GUITAR'S BODY

Mariana Domnica STANCIU
Drd. Eng. - Universitatea Transilvania din Brasov - Catedra de Rezistenta Materialelor si Vibratii Mecanice
Address: B-dul Eroilor nr. 29, Brasov, Romania
E-mail: mariana.stanciu@unitbv.ro

Nicolae CRETU
Lecturer Dr. Eng. - Universitatea Transilvania din Brasov - Catedra de Fizica
Address: B-dul Eroilor nr. 29, Brasov, Romania
E-mail: cretu.c@unitbv.ro

Calin ROSCACalin ROSCA
Prof. Dr. Eng. - Universitatea Transilvania din Brasov - Catedra de Rezistenta Materialelor si Vibratii Mecanice
Address: B-dul Eroilor nr. 29, Brasov, Romania
E-mail: icrosca@unitbv.ro

Ioan CURTU
Prof. Dr. Eng. - Universitatea Transilvania din Brasov - Catedra de Rezistenta Materialelor si Vibratii Mecanice
Address: B-dul Eroilor nr. 29, Brasov, Romania
E-mail: curtui@unitbv.ro

Abstract: The paper is focused on the experimental results regarding the dynamical behaviour of lignocellulose plates from the guitar's body in the case of free vibrations. Within the first part of the paper, the method of the impact hammer, the structure of the trial stand used and the types of the studied plates are depicted. Within the second part, the results of the experimental studies concerning the values of logarithmic decrements, the damping ratio and the natural frequencies of plates made of different species are presented. The results obtained were compared to that ones obtained by using analytical and numerical methods. The obtained data refer to the Romanian guitars produced at S.C. Hora S.A. Reghin.

Key words: underdamped free vibrations, natural frequency, logarithmic decrement, damping ratio, lignocellulose plates.

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