الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Pressure pulsations and mechanical vibrations in pipe systems may cause excessive noise and may even lead to damage of piping. or machinery. The excitation mechanism can be hydraulic or mechanical. In fluid-filled pipe systems pulsations and vibrations will be strongly coupled. In the thesis we will show some calculation and measurement methods for some scholars that have been developed for the analysis of vibrations and pulsations in fluid-filled pipe systems, taking fluid¬structure interaction into account.A calculation model has been developed for the simulation of pulsations and vibrations in fluid-filled pipe systems. The analytical model is based on the transfer matrix method. It describes pressure waves in the fluid and axial extensional waves, bending waves and torsional waves in the pipes. Fluid pulsations and mechanical vibrations are coupled at discontinuities (like elbows and Tjunctions) and via Poisson contraction of the pipe wall. For a given source description the model calculates pulsation and vibrations levels, but also. for example mode shapes and vibro-acoustic energy flow. The practicability of the calculation model and the effects of fluid-structure interaction are illustrated by calculations for some simple systems.In this thesis concerns the dynamics of the pipes conveying incompressible laminar flllid, where the pipe is supported on equally-spaced pinned supports. The equation of motion for fluid inside the pipe is estimated. The maximum amplitude of vibration was determined to avoid resonance effect. The damage of control valves used for pipes causes this leakage. Effect of exciting force according to the nature of leakage (harmonic, repeated pulses, repeated impulses) in pinned pinned beam was compared. Natural frequencies and the mode shape of the pipe related to the position of leakage and its amount were studied.A comparison between the different types of leakage and their position were obtained as a vibration effect. Pipe response ofthe portion before and after leakage was concerned. Also, the best position of the control valve supported on the pipe was selected to avoid high vibration acting on tpipe.Vibration or vibration related high cycle fatigue of small bore piping has been one of the main issues for maintaining the integrity of nuclear piping. Mitsubishi Heavy Industries (MHl) has been involved in root cause analysis of a number of leakage events in Japan, and accumulated and developed technology for piping design procedure or preventive maintenance activities of existing plants, from those experiences over 20 years. The concept and the outline of these technologies such as vibration measurement evaluation procedure, selection of vibration sensitive location, structural modification of cantilever type small bore branch pipe and positive countermeasure device for suppressing vibration are introduced.