A number of upper stages (e.g., the Centaur upper stage of Saturn IV) have been able to perform restarts of their main engines. For this purpose, an additional hot gas system is used for resettling of the bulk liquid propellant. De Brock et al. (1971) mentioned the extension of propellant-management devices (PMDs) for cryogenic expulsion systems. In future cryogenic upper stages of spacecrafts, PMDs can be used to position the liquid propellant over the tank outlet to ensure a gas-free supply of liquid propellant. The shape and stability of interfaces between two rotating circular parallel disks with another meniscus in a central tube on top of the upper disks is studied. SE-FIT is used to identify the critical Bond number Boc as a function of the distance between the disks b*, the radius of the central tube c*, and the number of segments. For this purpose, SE-FIT was benchmarked by computations of Boc for menisci in a rotating circular cylinder. The results are in good agreement with experiment by Seebold and numerical integration of the Young-Laplace equation. The shapes of the menisci in the tube and between the disks computed by numerical integration match the results of the computations with SE-FIT as well. In general, for the examined model an increasing number of segments n and a decreasing b* tend to stabilize the interface between the disks. For the computed models with a relatively small distance between the disks (i.e., b* ≤ 0.05), the instability is unsymmetrical. The break-up of the menisci between the disks occurs at two locations for b* = 0.1 and n < 16. With increasing n, the instability occurs at two adjacent segments. For b* ≥ 0.15, the instability occurs symmetrically for all computed model configurations. Results of the performed drop-tower tests show deviation from the results of the numerical computations. In the experiments, the menisci between the prarallel disks collapse into the liquid film along the tank wall. SE computations show that the interface between the disks becomes unstable if the maximum radius on the interface exceeds 1.095. This corresponds to a radius of 164.3 mm in the experiments for the model with R = 150 mm and the tank radius of 175 mm (gap size of model and tank is 25 mm). To reduce the probability of the meniscus between the disks collapsing into the liquid film at the tank wall in microgravity, a larger gap size between the outer edge of the disks and the tank wall shall be chosen,. The liquid around the model has to be transported away from the model by devices such that the free surfaces between the disks and in the central tube can be established in microgravity without being connected to the bulk liquid in the test cell. Additionally, dynamic effects caused by, for example, reorientaiton, eccentricity, or the removal of the sealing of the central tube should be evaluated properly, sharp edges for the two disks cannot be achieved due to manufacturing tolerances. To quantify the dynamic effects, computations with, for example, OpenFOAM are being undertaken.


    Zugriff

    Zugriff über TIB

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Study of rotating menisci in a generic propellant-management device


    Weitere Titelangaben:

    Untersuchung rotierender Minisken in einem generischen Treibstoff-Management-Gerät


    Beteiligte:

    Erschienen in:

    AIAA Journal ; 51 , 8 ; 1982-1992


    Erscheinungsdatum :

    2013


    Format / Umfang :

    11 Seiten, 19 Bilder, 4 Tabellen, 29 Quellen




    Medientyp :

    Aufsatz (Zeitschrift)


    Format :

    Print


    Sprache :

    Englisch




    Study of Rotating Menisci in a Generic Propellant-Management Device

    Reichel, Yvonne / Dreyer, Michael E. | AIAA | 2013





    Convergence Behavior of Surface Evolver Applied to a Generic Propellant Management Device

    Collicott, S. H. / American Institute of Aeronautics and Astronautics | British Library Conference Proceedings | 1999