Techno Press
You logged in as Techno Press

Advances in Aircraft and Spacecraft Science
  Volume 10, Number 5, September 2023 , pages 439-455

Frequency analysis of liquid sloshing in prolate spheroidal containers and comparison with aerospace spherical and cylindrical tanks
Mohammad Mahdi Mohammadi, Hojat Taei, Hamid Moosazadeh and Mohammad Sadeghi

    Free surface fluid oscillation in prolate spheroidal tanks has been investigated analytically in this study. This paper aims is to investigate the sloshing frequencies in spheroidal prolate tanks and compare them with conventional cylindrical and spherical containers to select the best tank geometry for use in space launch vehicles in which the volume of fuel is very high. Based on this, the analytical method (Fourier series expansion) and potential fluid theory in the spheroidal coordinate system are used to extract and analyze the governing differential equations of motion. Then, according to different aspect ratios and other parameters such as filling levels, the fluid sloshing frequencies in the spheroidal prolate tank are determined and evaluated based on various parameters. The natural frequencies obtained for a particular tank are compared with other literature and show a good agreement with these results. In addition, spheroidal prolate tank frequencies have been compared with sloshing frequencies in cylindrical and spherical containers in different modes. Results show that when the prolate spheroidal tank is nearly full and in the worst case when the tank is half full and the free fluid surface is the highest, the prolate spheroidal natural frequencies are higher than of spherical and cylindrical tanks. Therefore, the use of spheroidal tanks in heavy space launch vehicles, in addition to the optimal use of placement space, significantly reduces the destructive effects of sloshing.
Key Words
    fourier series expansion; free surface oscillation; potential fluid theory; sloshing frequencies; spheroidal containers
Mohammad Mahdi Mohammadi, Hojat Taei, Hamid Moosazadeh: Faculty of the Mechanic, Malek Ashtar University of Technology, Tehran, Iran
Mohammad Sadeghi: Department of Aerospace Engineering, Tarbiat Modares University, Tehran, Iran

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2024 Techno Press
P.O. Box 33, Yuseong, Daejeon 305-600 Korea, Tel: +82-42-828-7996, Fax : +82-42-828-7997, Email: