Comparison of Modal Analysis Using FEM and Eigenfrequency Measurements

In ultrasonic testing the vibration spectrum must be understood and the measured frequency peaks should match specific sample characteristics. In this paper, the experimental data are compared with results obtained using modal analysis based on Finite Element Method and the vibration was also calculated using classical Euler-Bernoulli approach, which is very simple but somewhat limited. The specimen geometry as well as the material of choice are both very simple to predict, model and measure - i.e. round cross section metal rod. In this case the FEM gives slightly better result that the simplified analytical calculation.