Simulation of Vibration Characteristics on the Artificially Corroded Elbow With Spectral Estimations

A Nuclear Power Plant has very sophisticated piping systems operating in a very aggressive erosion and corrosion environment with turbulent flow, high temperature and pressure. These adverse operating environments make a piping system very vulnerable to accelerated wear and degradation. But there is no practical way to monitor the wear and degradation during operation. In this study, we suggested and investigated the monitoring methodology for the wear and degradation of the piping system by using the accelerometer. The suggested methodology was based on the changes of the vibration mode due to the corrosion on the pipe. The accelerometer could be used to monitor the vibration of the system. For confirming the change of the characteristics of the vibration signals due to the corrosion, we simulated the vibration mode of piping system with artificially corroded elbow. For simulating the corroded piping system, we made three artificially corroded elbows. For analyzing the characteristics of the vibration signals, we used the power spectrum density with auto-regressive model. From simulation and analysis, we had a signature for wear and degradation on the piping system