矩形水槽壁の接水振動について

抄録

When side-walls of a rectangular tank which is filled with water is vibrating, the water will also make a vibratory motion. The author has made a calculation of the amount of kinetic energy of vibratory motion of water thus set up. The calculation was carried out about four specific cases as follows, the opposite two side-walls being assumed to be vibrating as shown by Fig. 1; (A). The rectangular tank is completely full of water, the two side-walls making “in-phase” vibrations to each other. (B). The same as (A), but two side-walls are vibratiag in “opposite phases” to each other. (D). The rectangular tank is almost filled up with water, but there is left on top a small vacancy. The two side-walls are making “in-phase” vibrations. (C). The same as case (D), but two side-walls are vibrating in “opposite phases” to each other.
From the calculated values of kinetic energy of vibrating water, we deduced the value of so-called “virtual mass” of water, with regard to vibration of side-walls of the rectangular tank. This will enable us to make an approximate estimation of the value of natural frequency of vibration of sidewall of the rectangular water tank. The calculation throughout is made, regarding the water to be an incompressible, non-viscous fluid, and the amplitude of vibration to be infinitesimally small.