Forced mixing may be required for on-orbit storage and transfer of cryogens. To provide applicable data on jet-induced mixing, an experiment was conducted in which an axial jet mixer promoted condensation of the ullage and lowered the pressure in a subscale cylindrical tank partially filled with Freon 11. The test objectives where to determine the transient condensation and heat transfer rates at the liquid-vapor interface as a function of jet parameters, quantify the important factors affecting mixing efficiency, and compare mixing times to previous mixing data based on acid-base neutralization and dye dispersion. The variation of interface heat transfer coefficient with changes in jet Reynolds number was consistent with existing correlations based on measurements of steady-state rates of mixing-induced condensation of steam. Mixing times based on tank pressure decay were correlated with jet momentum flux, although buoyancy effects made it difficult to extrapolate all the results to low gravity. Mixers with large diameter nozzles and low flow rates required the most time and least amount of energy to destratify the fluid. Dimensionless mixing times agreed with comparable acid-base neutralization data, but not with dye dispersion data.
Mixing-induced ullage condensation and fluid destratification
Mischungsinduzierte Leckkondensation und Abbau der Fluessigkeitsschichtung
AIAA-Papers ; Jul ; 1-11
1987
11 Seiten, 15 Bilder, 14 Quellen
Conference paper
English
Ullage Mixing Effects on Tank Pressurization Performance
AIAA | 1971
|Ullage mixing effects on tank pressurization performance
AIAA | 1970
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