AN INVESTIGATION OF THE NATURAL FREQUENCIES AND MODE SHAPES OF LIQUIDS IN OBLATE SPHEROIDAL TANKS

An experimental investigation was conducted to gain some understanding of the character of the free vibration modes of liquids in oblate spherodial tanks applicable in missile and space vehicle systems. Measured natural frequencies were obtained for the lowest three or four antisymmetric modes of oscillation as a function of the liquid depth for three orientations of each of several such tanks of different size and oblateness. The frequency data are presented as dimensionless parameters developed for each orientation to permit the application of the experimental results to the prediction of the natural frequencies of tanks of different size and oblateness. Photographs were made of representative surface wave or mode shapes for each orientation. (Author)