基于PSD的静电悬浮液滴振荡技术在表面张力与黏度测量中的应用

摘要

位置敏感探测器PSD(position sensitive detector)具有成本低、响应速度快、探测灵敏度高的特点,文中结合一维P SD和静电悬浮技术,提出一种新的悬浮液滴振荡测量的方法,可以高精度地测量高温熔融材料的表面张力和黏度系数.稳定悬浮的样品通过半导体激光器加热到熔融状态后,在位置控制信号上叠加一段频率和幅值可调的正弦振荡信号,利用一维P SD采集稳态振荡后的衰减信号,通过频谱分析和指数函数拟合得到样品的共振频率和衰减时间.利用纯金属锆进行熔融液滴振荡测量的实验,计算得到液态金属锆的表面张力和黏度系数,验证了该测量方法的有效性.%PSD (position sensitive detector) had the advantages of low cost,fast response and high sensitivity.By combing one-dimensional PSD with electrostatic levitation,an advanced levitated droplet oscillation method was proposed to measure the surface tension and viscosity of high-temperature molten materials with high precision. After the levitating sample was heated by semiconductor lasers and melt,the output position controlling signal was added by a period of sinusoidal oscillatory signal which frequency and amplitude were adjusted.The decay signal after stable oscillation was captured by one-dimensional PSD and ana-lyzed by spectrum transform to get the resonant frequency and fitted by exponential function to get decay time.A pure Zr sample was experimented to measure molten droplet oscillation.By calculating the surface tension and viscosity of molten Zr droplet,the measuring method is verified.