抄録
Under the microgravity environment, liquid can be treated without container due to weightless. Therefore physical properties of a material are expected to be measured with a high accuracy. In surface tension measurement of levitated droplet, it is calculated by using the formula derived under the assumption of linearity of the resonant frequency. However, it is indicated that the resonant frequency of a droplet changes with oscillation and rotation. So the purpose of this study is to examine effect of oscillation and rotation on the resonant frequency experimentally. A droplet is levitated by using electrostatic levitator, and induced to oscillate and rotate. Resonant frequency, aspect ratio, amplitude and rotational velocity are measured from droplet motion. It is confirmed oscillation and rotation effect on aspect ratio and resonant frequency. And the frequency shift becomes zero under the appropriate combination of amplitude and rotational velocity. It is experimentally clarified that the resonant frequency is strongly related with time average of aspect ratio.
