Numerical Modal Analysis of Kinked Bars –Triangle Case of Study

Abstract

The paper deals with numerical modal analysis of a kinked bars similar with an open triangle, with different sizes, angles and diameters of bar. Using SIMCENTER software, the first step was to design the geometry of each type of structure, then discretization of model in finite elements and assigning properties of material (in this case, Al alloy). The results in terms of eigenvalues and eigenmodes of each structure revealed that the angles of kinked bars influenced the value of natural frequency: with increase the tip angle from 30° to 60° and 90°, the eigenvalue decreased in ratio of 1:1.39:1.611. Also, the length of each side of the kinked bar influences the modal response of the structure: increasing the length from 200 mm to 450 mm, leads to decreases of eigenvalue of almost 5.6 times. The applicability of this study is linked to percussion instruments used in musical orchestra and also to explain the energy transfer and acoustic effect of different types of triangle instruments.