1998 Fiscal Year Final Research Report Summary

Nonlinear Stability of the Lateral Vibration of a Fluid-Conveying Pipe

Research Project

Project/Area Number	09650277
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Dynamics/Control
Research Institution	Keio University
Principal Investigator	YOSHIZAWA Masatsugu Keio University, Department of Mechanical Engineering, Professor, 理工学部, 教授 (10095664)
Project Period (FY)	1997 – 1998
Keywords	Nonlinear Dynamics / Cantilevered Pipe / Lumped Mass / Flow-Induced Vibration / Nonplanar / Horizontal Excitation / Qualitative Analysis / Experiment
Research Abstract	In this paper, the nonlinear lateral vibrations of a cantilevered pipe, which is hung vertically with an end mass and conveys fluid, are examined theoretically and experimentally under the supercritical condition that planar and nonplanar pipe vibrations are self-excited due to an internal flow above the critical velocity. First, the effect of an end mass on the pipe vibration is discussed theoretically with the nonlinear coupled equations of the lateral deflections of the pipe. Second. the experiments were conducted with a silicon rubber pipe conveying water. The spatial behaviors of the fluid-conveying pipe were observed by means of the image-processing system based on the images from two CCD cameras. Furthermore it is examined for the case that the upper end of the pipe is excited periodically in a horizontal direction.