ADDED MASS ON VIBRATING MEMBRANE ROOFS

Abstract

Added mass on vibrating membrane roof in the air is investigated analytically and experimentally, including parameters such as various vibration modes and aspect ratio of flat plate. Finite Element Method (FEM) is applied to estimate added mass based on the theory of velocity potential. A series of free vibration tests on aluminum beams with various aspect ratios are conducted in the normal air and a vacuum chamber. The natural frequency difference between both environment conditions is used to evaluate added mass of air. Numerically-obtained added mass coefficients and experimental ones are almost identical. Based on these results, modal added mass coefficient of flat plate is formulated empirically as a function of aspect ratio and vibration mode.