一种转动容器中磁流体液表面形貌测量方法

Surface Topography Measurement of Magnetic Fluid in Revolving Containers

针对旋转容器中磁流体液表面形貌测量,提出了一种基于线型激光同步斩波调制投影的多步测量方法。采用与容器同步转动窗口斩波调制的线型激光投影方法获得了稳定的磁流体表面投影线,同时采用长时间多圈测量的平均和亮度增强效应,获得了高亮度和对比度的磁流体表面投影线;采用高透光率的亚克力盖板,实现了磁流体密封与高透光测量的双重功能,研究并给出了考虑亚克力板折射率对测量结果影响的磁流体高度测量公式;构建了磁流体形貌测试实验台,并开展了不同转速、不同磁场强度下磁流体的形貌测量验证实验,通过多组实验测量提高精确度,并与理论分析进行磁流体变化规律对比验证。通过这种实验方法可测量在旋转运动中的磁流体表面形貌,真实反映磁流体受到磁场、离心力作用下的运动状态。

Aiming at the measurement of surface topography of magnetic fluid contained in revolving containers,a multi-step measurement method based on the synchronous chopper modulated linear laser projection was proposed.According to the principle of linear laser projection measurement,synchronous revolving window chopper modulated laser is introduced to obtain the steady projection light curve on the surface of magnetic fluid.In the meantime,taking the advantages of multi-revolving averaging and lightness enhancing effect of long exposure time,the projection light curve pictures with high brightness and contrast were obtained.A high transparency acrylic plate was adopted to guarantee good sealing performance and light transmission quality in the experiments.The height formula of magnetic fluid surface was deduced,in which the influence of refractive index of the acrylic plate on the measurement results was taken into account.Experiments were carried out under different revolving speeds and magnetic field intensities to verify the accuracy of the proposed method.The method can measure the surface topography of magnetic fluid in revolving containers,and truly reflect the motion state of the magnetic fluid under magnetic and centrifugal forces.