different scenarios for a PMD of a cryogenic tank during the ballistic flight phase (CFM LOX PMD)

abstract

In this project different possible scenarios were analyzed which can occur to a reignitable tank system of spacecraft during non-driven flight phases. The main focus is on a refillable reservoir which is assembled on the axis of rotation near the tank outlet, the so-called PMD (here for the LOX tank). This reservoir shall accumulate a required amount of liquid propellant to enable vapor- and gas-free expulsion of liquid for reignition. The process of accumulation of liquid within the structures of a model of a PMD was observed during several experiments. Additionally, the gas-liquid interfaces during draining were investigated. This setting represents the expulsion of liquid propellant to the tank outlet. A critical scenario can be caused by rotation during the ballistic flight phases since the lateral acceleration drives the liquid propellant away from the tank outlet and the refillable reservoir. For this case the free surfaces of a partly and totally filled model of the PMD were observed for various angular speeds.

• Reichel, Y., Dreyer, M.E.: Analysis of Critical Disturbances for Propellant Management Devices in Future Cryogenic Upper Stages, 47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, San Diego, California, AIAA 2011-6036, 2011

experiment year: 2011
number of drops: 7 (draining), 10 (refilling), 20 (spilling)
number of catapult flights: 2 (spilling - pre-tests)