Vibroacoustic Diagnostics Based on the Experimental and Numerical Approach

Abstract

During the last decade, many developers in the engineering industry are focusing on diagnostics and effective eliminating of the vibration and noise. The vibration and acoustic emissions are directly related to each other. Based on this fact, it is important to take into consideration the original vibration sources (engine, gearbox), but also the radiated noise to the environment. Current time brings unprecedented possibilities in the field of laboratory measurements and computational simulations in terms of hardware and software. In the issue of vibroacoustic diagnostics, the combination of these two approaches is very often required. In the first phase, the modal properties of the structure are usually examined, and the material properties are defined according to the mutual validation from both approaches. Subsequently, the amplitudes in structural (normal acceleration of the surface) and acoustic domain (sound power level—SWL, sound pressure level—SPL) are monitored during the operating conditions. In laboratory conditions, the structure is often excited by a mode exciter. In this case, the maximum amplitudes at the specific locations are primarily recorded on the structure. This article systematically describes the vibroacoustic diagnostics of the rectangular plate. Two approaches are explained in the paper: experimental and computational—based on the finite element method (FEM). In the text below, the individual procedures of the two methodologies are described. The obtained results from modal and harmonic response analyses are validated and compared with each other.