PERIODIC WAVE PROPAGATION IN LIQUID TRANSMIS- SION LINES WITH VARIABLE SPEED OF SOUND

Instituteof MachineDesignandHydraulicDrives, JohannesKepler University,Altenbergerstr.69, 4040 Linz, Austria, e-mail: bernhard.manhartsgruber@jku.atLiquid transmission lines are used in a large number of technologies from water distributionand oil pipelines to the high pressure applications in hydraulic drives and fuel injection. Dueto various physical effects the idealization of a weakly compressible fluid with a constantbulk modulus of compressibility resulting in a constant wave speed becomes insufficient in anumber of interesting applications. The present paper presents simulation results for a simplecase where a single transmission line is excited by a sinusoidal flow rate at one end while theother end is blocked. The flow equations are discretized both in time and space resulting in ahuge equation system to be solved for the periodic solution.