الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In the present study, dynamic fluid pipe coupling is analyzed taking into considerations, the outside friction on pipe wall. The problem is analytically solved using the method of characteristics. This approach helps to clarify, the centrifugal pump effect on the hammering waves, based on the characteristic equations, to estimate the maximum and minimum values of pressure, stress wave, damping time, and hammering wave shape. Streeter program is developed to solve four equations model to estimate the maximum and minimum values of pressure and stress. Also programs illustrate the position of maximum hammering wave’s effect along the pipe line due to change in valve closing time. Theoretical and experimental results indicate that; for the same condition the maximum pressure resulted from the four equations model is less than resulted from the two equations model. Also in case of using four equations model with valve closing time less than or equal ten times the wave period, as the distance from the pump increases, the maximum pressure increases, and with valve closing time more than ten times the wave period, the minimum pressure value reaches at the middle sections of the pipe, and the maximum stress values occur at the middle sections of the pipe. This information is useful in pipe design.