Bondgraph analysis on pressure fluctuation in hydraulic pipes

The bond graph method is a unified approach to represent a system combined with mechanical, hydraulic and electrical sub-systems. Recently, this method has been used to design hydraulic systems as well as to analyze their dynamic characteristics. Pipes are indispensable for hydraulic systems as an element transporting hydraulic power between components. Pipes often play an important role on pressure fluctuations. Considering a total hydraulic system, it is important and convenient to use a unified approach to analyze the dynamic characteristics in the other components as well as pipes. A basic bond graph model of a pipe has already been established as a lumped parameter system. With the reliability of the lump model of a pipe, a bond graph method would be more useful and more convenient for designing hydraulic circuits. The reliability of a bond graph lump model of a pipe on pressure fluctuations was investigated by using a straight and connected pipe through comparing the results by bond graphs with the results by a characteristic method and experiments. This study proved that a bond graph lump model showed the same precision as other results with a suitable number of pipe element lump models.