Fluid Transient Analysis During Priming of Evacuated Line
Pressure surges are critical in the design of spacecraft propellant feed lines. The pressure transients that occur during priming of feed lines are very important in the design and analysis of liquid propulsion systems. During the start-up of the propulsion system of a spacecraft, the process of filling of an evacuated pipeline is called priming. Priming can generate severe pressure peaks due to the slam (water hammer) of the propellant against a closed thruster valve. The downstream conditions strongly affect the pressure surge. In space systems, satellites, or interplanetary probes, the propellant lines are vacuum-pumped or filled with low pressure helium or nitrogen before the launch. Before operations, these lines are primed with a vaporizing liquid, sometimes in the presence of a non-condensable gas (NCG), which produces water hammer phenomena. The objective of the current study is to use a finite volume based network flow solver (Generalized Fluid System Simulation Program, GFSSP) for the numerical simulation of Priming in (a) a straight feedline and (b) a flow network. The geometrical configurations and dimensions for the pipe and other components used for the current study are identical to experimental study of Prickett et al.