Vibration Control in Piping System by Dual Dynamic Absorber : Realization of Piping Systems with Unresonant Characteristics

This paper shows the design method for constructing a piping system with well-suppressed resonance peaks through a wide range of frequencies. The piping system is strongly influenced by sources of excitation for blade vibrations since it is usually made flexible and has a low damping property. Thus, many problems, like fatigue damage or noise caused by vibration, occur frequently in the piping system. In order to suppress the resonance peaks and obtain high damping, dual dynamic absorbers proposed in the previous paper are applied. In this paper, it is confirmed theoretically by the transfer matrix method that the piping system with seven resonance peaks within l00 Hz is well suppressed by using five dynamic absorbers. The effectiveness of the five optimally designed dual dynamic absorbers is also demonstrated experimentally.