Sound spreading within a body is called structure-borne sound. This includes as different phenomena as vibrations and earthquakes but also the transmission of oscillations in buildings, vehicles and machines.
Piston engines and other intermittently working machines conduct oscillations regarded as distracting from inertia forces e. g. into foundations, decks of ships and car bodies. Therefore, limit values are specified which must not be exceeded.
Often, these limit values are frequency dependent and are described by allowed limit curves of the acceleration level at the base points (supporting points). In order to reduce vibration impact in the base points, systems are being isolated by elastic mounts.
Merkle & Partner manages the complete virtual process starting with the formation of intermittent forces with MBS models through the elastic response of the system by FE computations up to the calculation of the acceleration level as a function of the frequency by a Fourier transformation from the temporal results. Resonances can be recognized and eliminated. Mount rigidities can specifically be optimized. Thus, results are known before the machines are built and tested!