Abstract
Nonlinear lateral vibration of a vertical cantilevered pipe with an end mass is studied for the case that the upper end of the pipe is excited periodically in a horizontal direction. The fluid velocity of an axial flow in the pipe is slightly over the critical value, above which lateral pipe vibration is self-excited by an internal flow. First, the effect of horizontal excitation on nonplanar flow-induced pipe vibration is examined by solving numerically the four first-order ordenary differential equation, which govern the amplitudes and phases of nonplanar pipe vibration and are coupled though the nonlinear terms. Second, the experiments were conducted with a silicon rubber pipe conveying water, and the spatial behavior of the pipe vibration were observed using two CCD cameras. The typical effect of horizontal excitation, which has been predicted in the theory, is confirmed qualitatively by experiment.
