Dynamic Characteristics of Cantilever Pipe Conveying Fluid with Moving Mass Considering Nozzle Angle

J. Ocean Eng. Technol. 2002;16(6):18-24.

노즐 경사각을 고려한 이동질량을 가진 유체이송 외팔 파이프의 동특성 해석

윤한익,손인수,김현수,조정래

동의대학교 기계산업시스템공학부,동의대학교 대학원 기계공학과,동의대학교 대학원 기계공학과,경북직업전문학교 자동차과

Keywords: Cantilever Pipe Conveying Fluid, Dynamic Characteristics, Moving Mass, Naturnal Frequency, Nozzle Angle

핵심용어: 유체이송 외팔관, 동적특성, 이동질량, 고유 진동수, 노즐 경사각.

Abstract

The vibrational system in this study consists of a cantilever pipe conveying fluid, the moving mass upon it, and an attached tip mass. The equation of motion is derived by using the Lagrange equation. The influences of the velocity and the velocities of fluid flow in the pipe have been studied on the dynamic behavior of a cantilever pipe using a numerical method. While the moving mass moves upon the cantilever pipe, the velocity of fluid flow and the nozzle angle increase; as a result, the tip displacement of the cantilever pipe, conveying fluid, is decreased. After the moving mass passes over the cantilever pipe, the tip displacement of the pipe is influenced by the potential energy of the cantilever pipe and the deflection of the pipe; the effect is the result of the moving mass and gravity. As the velocity of fluid flow and nozzle angle increases, the natural frequency of he system is decreased at the second mode and third mode, but it is increased at the first mode. As the moving mass increases, the natural frequency of the system is decreased at all modes.