EXPERIMENTAL INVESTIGATION OF LIQUID SLOSHING IN A CRYO UPPER STAGE TANK DEMONSTRATOR IN

Abstract

the shape of the tank bottom and for various fill level. The tank bottom shapes are given as flat bottom and convex formed bottom. The sloshing phenomena are investigated on a hexapod with 6 degrees of freedom movement. The model tank is mounted on the hexapod platform and partly filled with deionized water as test liquid. The platform can be forced to a defined motion. During the test the free surface behavior is recorded with a laser measurement system. The sloshing forces are measured with force transducers. Experimental results on eigenfrequency and damping ratio will be presented as function of fill level for both tank bottom shapes. The results show that there is a significant influence of the damping behavior for the different bottom shapes. A correlation will be presented and compared with data from literature. The experimental correlations are an important contribution for the understanding and consideration of sloshing effects for preliminary spacecraft design. Based on this work, the present tank demonstrator will be used in future to investigate the sloshing behavior of cryogenic propellants.