Study on Non-linear dynamics of levitated droplet

升降滴的非线性动力学是通过实验对超声波升降装置和电静态升降装置进行调查的，以及通过理论分析和数字分析进行调查的。根据结果，下面的内容被揭示了。新的技术对viscosity的度量为0.1到100 （Pa·s）的viscosity范围。在过去是不可能衡量0.1到100的波动中的可见性。在一个高水平的水滴中，三个尺寸流动的新测量技术是根据高水平水滴中的三个尺寸PTV技术开发的。三种尺寸的PIV测量方法是根据飞机上正常重力状况和微观重力状况进行的。非线性分析理论最近被开发用于提高水滴的非线性表面变形。一个三维模拟代码已经根据级别集方法开发出来，在Navier-Stokes equation的流体运动与接口动力学的等式配对。模拟代码是并行的，并且是一个旋转-振荡液体滴液的数字模拟。这表明，当频率增加时，频率减少时，频率增加。在水滴中发现了一个压力场，与频率的变化密切相关。视觉和表面张力对频率转换的影响已经变得清晰了。

Non-linear dynamics of levitated droplet is investigated by the experiment with ultrasonic levitation apparatus and electrostatic levitation apparatus, and by the theoretical analysis and numerical analysis. As the results, followings are revealed.・New technology to measure the viscosity with the levitated droplet is developed for the viscosity range of 0.1 to 100 (Pa・s). In past it is impossible to measure the viscosity in the rage from 0.1 to 100 (Pa・s).・New measurement technologies of the three dimensional flow in a levitated droplet are developed based on the three dimensional PTV technique from the stereo image measurement of the levitated droplet.・The three dimensional PIV measurements are conducted under the normal gravity condition and micro gravity condition with parabolic flight in aircraft. Non-linear analysis theory is newly developed for the non-linear surface deformation of the levitated droplet.A three-dimensional simulation code has been developed based on the level set method, in which the Navier-Stokes equation for fluid motion was coupled with an equation for interface dynamics. The simulation code was parallelized, and numerical simulations of a rotating-oscillating liquid droplet were performed. It was shown that the frequency decreased as the amplitude increased, while the frequency increased as the rotation increased. The pressure field in the droplet was found to be closely related to the frequency shift. The effects of viscosity and surface tension on the frequency shift were made clear.