Surge event mitigation in propulsion systems

A research program was performed to evaluate pressure transient levels generated by water hammer effects resulting from a beginning of life surge event in both unrestricted and restricted liquid monopropellant propulsion system configurations. This was conducted through experimental testing with distilled water in an existing water hammer setup. Multiple test elements were evaluated using numerous internal diameters, manifold layouts, and flow control valves, under atmospheric and near-vacuum pressure levels. The goals of the research were to determine the influence of restrictions in a propulsion system, as well as the propellant manifold design, in the mitigation of the surge event maximum pressure levels. Furthermore, recommendations will be made on the preferred propulsion system layouts that minimize the potential for surge event damage, such that the peak surge pressure is below the proof pressure of any component in the liquid flow circuit.