Investigation of Mechanical Based Suppression Device on Liquid Propellant Line Water Hammer Effects

One of the main design considerations in liquid propulsion system’s propellant line integrity is the formation of the water hammer shocks. These shocks may arise in priming operations and thrust termination processes in which sudden cessation of the fluids can occur. These water hammer shocks may cause severe effects in pipeline system such as leakage, stocked valves, broken filtering elements or bursts in flexible hoses. In this study, tests were conducted in the experimental setup that simulates a pressure fed single line propulsion system. In the tests two different pipe lengths, three different pipe diameters were considered whereas three different tank pressures were tested. A mechanical-based ‘water hammer suppression device’ (WHS device) that employs a spring is used for the suppression of the water hammer shocks. The WHS device’s performance was compared to the cases where there is no precaution was taken to suppress the formation of a regular line water hammer shocks. Furthermore, effect of the selection of the spring employed by the device was obtained by using three springs with different spring constants. The comparisons were made based on damping performances by considering percent reduction in the peak pressures obtained from dynamic pressure transducers. The conducted tests showed that, depending on the configuration, water hammer shocks can be suppressed up to 88.5% compared to reference case by the proposed mechanical-based device.