LOCALIZATION OF HIGH-FREQUENCY VIBRATIONS OF SECONDARY SYSTEMS OF POWER-PLANTS

The papers addresses a new approach for more accurate dynamic design o f secondary systems and components of nuclear power plants at high fre quencies. This approach is based on a precise consideration of a struc tural member with the rest of the structure being described integrally . The concept is applied to analyse the transition of high-frequency v ibrations through non-anchored coupling of structural members which is known to be an effective measure against low-frequency excitation pro pagation. The theory of high-frequency vibrations is used for integral description of the whole structure. A structural member is represente d by an oscillator. A mechanical model comprising a spring in series w ith a dry damper which has a gap is applied in order to simulate non-a nchored coupling of structural members. It is shown that the phenomeno n of high-frequency vibration localization takes place for arbitrary m echanical parameters of the structure. This means that the substructur e's contact zone possesses a property of high-frequency vibration isol ation and the contact surface could be considered as a thin vibroisola ting layer which occurs between adjacent coupled substructures.