Vibration Transmission of Flexible Pipe Couplings Influenced by the Elements of a Trim-Pump System

摘要

An analytical-experimental study was performed to determine the sound transmission characteristics of a flexible coupling in a trim-pump system. Mechanical impedance methods were used to compare the structural path to the hull via resilient mounts and foundation to the structural path via flexible coupling and pipe hanger. Also investigated were the vibration characteristics of an Electric Boat and MEL flexible coupling under pressurized and unpressurized conditions. Results showed that the sound transmission viaflexible coupling and pipe hanger exceeded the sound transmission via the mount and foundation and would negate the isolation effectiveness of the primary mounting system. The results of comparing the two types of flexible coupling showed that the Electric Boat Coupling exhibited better total noise attenuation characteristics than did the MEL coupling. However, the MEL coupling showed a unique inherent characteristic of improved attenuation capabilities with increased pressure loading. (Author)