Graduate Studies


Date of this Version

Winter 4-17-2012


Waweru, Lawrence. "Random vibration analysis of cantilever pipes containing turbulent flow." MS thesis, University of Nebraska, 2013.


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Mechanical Engineering and Applied Mechanics, Under the Supervision of Professor Cho Wing Solomon To. Lincoln, Nebraska: May, 2013

Copyright (c) 2013 Lawrence Waweru


In this thesis a method of analyzing vibration of a piping system containing turbulent flow is pursued. Unlike previous investigations of such piping systems which use external excitation to initiate vibration, this investigation develops an analysis method using the fluid momentum to generate the starting vibration for the system. The law of conservation of momentum forms the basis of this study. The modified stochastic central difference (SCD) method that includes the spectral density of the random component of turbulent flow velocity, along with finite element method (FEM) application and the time co-ordinate transformation (TCT) are used here.

The SCD method has been used successfully in systems under stationary and non-stationary random excitations. In this investigation the SCD method is used in cantilevered piping systems that are represented by finite elements. The effects of turbulent flow velocity and temperature of the medium on the random responses have been examined. In parallel the computed responses of a cantilevered pipe containing turbulent flowing fluid are compared and agree with experimental results available in the literature.

Advisor: Cho Wing Solomon To