MASS-SPRING DESIGN MODEL PREPARING METHOD FOR SLOSHING ANALYSIS OF LIQUID IN TEARDROP SHAPE TANK

摘要

PROBLEM TO BE SOLVED: To make it possible to execute an analytical approach even to a non-axisymmetric problem such as a sloshing of a liquid in a teardrop shape tank and thus to attain reduction of calculation time and calculation cost. SOLUTION: This method assumes a central axis z of a teardrop shape tank 1 and a longitudinal section of a liquid 2 passing through an arbitrary position in a circumferential direction of a liquid level 4 of the teardrop shape tank 1, takes a polar coordinate system in the longitudinal section of each liquid 2, constructs a spherical coordinate system with this polar coordinate system and a circumferential direction coordinate of a part contacting a tank wall surface 5 of the liquid 4, and analytically decides by a superposition of orthogonal functions the solution to the Laplace equation Laplasian =0 ( is the velocity potential) which governs the liquid movement by using the spherical coordinates. Then, the liquid movement is discritized by an orthogonal function expansion, a problem is reduced to a simultaneous linear equations regarding the expansion coefficients, the simultaneous linear equations are solved and a mass-spring design model is prepared.